aboutsummaryrefslogtreecommitdiff
path: root/lib/AST/Decl.cpp
blob: 8eff4c4427b322c56ebc7c17f23441ec1bc017dd (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
//===--- Decl.cpp - Declaration AST Node Implementation -------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the Decl subclasses.
//
//===----------------------------------------------------------------------===//

#include "clang/AST/Decl.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/ASTLambda.h"
#include "clang/AST/ASTMutationListener.h"
#include "clang/AST/Attr.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/PrettyPrinter.h"
#include "clang/AST/Stmt.h"
#include "clang/AST/TypeLoc.h"
#include "clang/Basic/Builtins.h"
#include "clang/Basic/IdentifierTable.h"
#include "clang/Basic/Module.h"
#include "clang/Basic/Specifiers.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Frontend/FrontendDiagnostic.h"
#include "llvm/Support/ErrorHandling.h"
#include <algorithm>

using namespace clang;

Decl *clang::getPrimaryMergedDecl(Decl *D) {
  return D->getASTContext().getPrimaryMergedDecl(D);
}

// Defined here so that it can be inlined into its direct callers.
bool Decl::isOutOfLine() const {
  return !getLexicalDeclContext()->Equals(getDeclContext());
}

TranslationUnitDecl::TranslationUnitDecl(ASTContext &ctx)
    : Decl(TranslationUnit, nullptr, SourceLocation()),
      DeclContext(TranslationUnit), Ctx(ctx), AnonymousNamespace(nullptr) {
  Hidden = Ctx.getLangOpts().ModulesLocalVisibility;
}

//===----------------------------------------------------------------------===//
// NamedDecl Implementation
//===----------------------------------------------------------------------===//

// Visibility rules aren't rigorously externally specified, but here
// are the basic principles behind what we implement:
//
// 1. An explicit visibility attribute is generally a direct expression
// of the user's intent and should be honored.  Only the innermost
// visibility attribute applies.  If no visibility attribute applies,
// global visibility settings are considered.
//
// 2. There is one caveat to the above: on or in a template pattern,
// an explicit visibility attribute is just a default rule, and
// visibility can be decreased by the visibility of template
// arguments.  But this, too, has an exception: an attribute on an
// explicit specialization or instantiation causes all the visibility
// restrictions of the template arguments to be ignored.
//
// 3. A variable that does not otherwise have explicit visibility can
// be restricted by the visibility of its type.
//
// 4. A visibility restriction is explicit if it comes from an
// attribute (or something like it), not a global visibility setting.
// When emitting a reference to an external symbol, visibility
// restrictions are ignored unless they are explicit.
//
// 5. When computing the visibility of a non-type, including a
// non-type member of a class, only non-type visibility restrictions
// are considered: the 'visibility' attribute, global value-visibility
// settings, and a few special cases like __private_extern.
//
// 6. When computing the visibility of a type, including a type member
// of a class, only type visibility restrictions are considered:
// the 'type_visibility' attribute and global type-visibility settings.
// However, a 'visibility' attribute counts as a 'type_visibility'
// attribute on any declaration that only has the former.
//
// The visibility of a "secondary" entity, like a template argument,
// is computed using the kind of that entity, not the kind of the
// primary entity for which we are computing visibility.  For example,
// the visibility of a specialization of either of these templates:
//   template <class T, bool (&compare)(T, X)> bool has_match(list<T>, X);
//   template <class T, bool (&compare)(T, X)> class matcher;
// is restricted according to the type visibility of the argument 'T',
// the type visibility of 'bool(&)(T,X)', and the value visibility of
// the argument function 'compare'.  That 'has_match' is a value
// and 'matcher' is a type only matters when looking for attributes
// and settings from the immediate context.

const unsigned IgnoreExplicitVisibilityBit = 2;
const unsigned IgnoreAllVisibilityBit = 4;

/// Kinds of LV computation.  The linkage side of the computation is
/// always the same, but different things can change how visibility is
/// computed.
enum LVComputationKind {
  /// Do an LV computation for, ultimately, a type.
  /// Visibility may be restricted by type visibility settings and
  /// the visibility of template arguments.
  LVForType = NamedDecl::VisibilityForType,

  /// Do an LV computation for, ultimately, a non-type declaration.
  /// Visibility may be restricted by value visibility settings and
  /// the visibility of template arguments.
  LVForValue = NamedDecl::VisibilityForValue,

  /// Do an LV computation for, ultimately, a type that already has
  /// some sort of explicit visibility.  Visibility may only be
  /// restricted by the visibility of template arguments.
  LVForExplicitType = (LVForType | IgnoreExplicitVisibilityBit),

  /// Do an LV computation for, ultimately, a non-type declaration
  /// that already has some sort of explicit visibility.  Visibility
  /// may only be restricted by the visibility of template arguments.
  LVForExplicitValue = (LVForValue | IgnoreExplicitVisibilityBit),

  /// Do an LV computation when we only care about the linkage.
  LVForLinkageOnly =
      LVForValue | IgnoreExplicitVisibilityBit | IgnoreAllVisibilityBit
};

/// Does this computation kind permit us to consider additional
/// visibility settings from attributes and the like?
static bool hasExplicitVisibilityAlready(LVComputationKind computation) {
  return ((unsigned(computation) & IgnoreExplicitVisibilityBit) != 0);
}

/// Given an LVComputationKind, return one of the same type/value sort
/// that records that it already has explicit visibility.
static LVComputationKind
withExplicitVisibilityAlready(LVComputationKind oldKind) {
  LVComputationKind newKind =
    static_cast<LVComputationKind>(unsigned(oldKind) |
                                   IgnoreExplicitVisibilityBit);
  assert(oldKind != LVForType          || newKind == LVForExplicitType);
  assert(oldKind != LVForValue         || newKind == LVForExplicitValue);
  assert(oldKind != LVForExplicitType  || newKind == LVForExplicitType);
  assert(oldKind != LVForExplicitValue || newKind == LVForExplicitValue);
  return newKind;
}

static Optional<Visibility> getExplicitVisibility(const NamedDecl *D,
                                                  LVComputationKind kind) {
  assert(!hasExplicitVisibilityAlready(kind) &&
         "asking for explicit visibility when we shouldn't be");
  return D->getExplicitVisibility((NamedDecl::ExplicitVisibilityKind) kind);
}

/// Is the given declaration a "type" or a "value" for the purposes of
/// visibility computation?
static bool usesTypeVisibility(const NamedDecl *D) {
  return isa<TypeDecl>(D) ||
         isa<ClassTemplateDecl>(D) ||
         isa<ObjCInterfaceDecl>(D);
}

/// Does the given declaration have member specialization information,
/// and if so, is it an explicit specialization?
template <class T> static typename
std::enable_if<!std::is_base_of<RedeclarableTemplateDecl, T>::value, bool>::type
isExplicitMemberSpecialization(const T *D) {
  if (const MemberSpecializationInfo *member =
        D->getMemberSpecializationInfo()) {
    return member->isExplicitSpecialization();
  }
  return false;
}

/// For templates, this question is easier: a member template can't be
/// explicitly instantiated, so there's a single bit indicating whether
/// or not this is an explicit member specialization.
static bool isExplicitMemberSpecialization(const RedeclarableTemplateDecl *D) {
  return D->isMemberSpecialization();
}

/// Given a visibility attribute, return the explicit visibility
/// associated with it.
template <class T>
static Visibility getVisibilityFromAttr(const T *attr) {
  switch (attr->getVisibility()) {
  case T::Default:
    return DefaultVisibility;
  case T::Hidden:
    return HiddenVisibility;
  case T::Protected:
    return ProtectedVisibility;
  }
  llvm_unreachable("bad visibility kind");
}

/// Return the explicit visibility of the given declaration.
static Optional<Visibility> getVisibilityOf(const NamedDecl *D,
                                    NamedDecl::ExplicitVisibilityKind kind) {
  // If we're ultimately computing the visibility of a type, look for
  // a 'type_visibility' attribute before looking for 'visibility'.
  if (kind == NamedDecl::VisibilityForType) {
    if (const TypeVisibilityAttr *A = D->getAttr<TypeVisibilityAttr>()) {
      return getVisibilityFromAttr(A);
    }
  }

  // If this declaration has an explicit visibility attribute, use it.
  if (const VisibilityAttr *A = D->getAttr<VisibilityAttr>()) {
    return getVisibilityFromAttr(A);
  }

  // If we're on Mac OS X, an 'availability' for Mac OS X attribute
  // implies visibility(default).
  if (D->getASTContext().getTargetInfo().getTriple().isOSDarwin()) {
    for (const auto *A : D->specific_attrs<AvailabilityAttr>())
      if (A->getPlatform()->getName().equals("macosx"))
        return DefaultVisibility;
  }

  return None;
}

static LinkageInfo
getLVForType(const Type &T, LVComputationKind computation) {
  if (computation == LVForLinkageOnly)
    return LinkageInfo(T.getLinkage(), DefaultVisibility, true);
  return T.getLinkageAndVisibility();
}

/// \brief Get the most restrictive linkage for the types in the given
/// template parameter list.  For visibility purposes, template
/// parameters are part of the signature of a template.
static LinkageInfo
getLVForTemplateParameterList(const TemplateParameterList *Params,
                              LVComputationKind computation) {
  LinkageInfo LV;
  for (const NamedDecl *P : *Params) {
    // Template type parameters are the most common and never
    // contribute to visibility, pack or not.
    if (isa<TemplateTypeParmDecl>(P))
      continue;

    // Non-type template parameters can be restricted by the value type, e.g.
    //   template <enum X> class A { ... };
    // We have to be careful here, though, because we can be dealing with
    // dependent types.
    if (const NonTypeTemplateParmDecl *NTTP =
            dyn_cast<NonTypeTemplateParmDecl>(P)) {
      // Handle the non-pack case first.
      if (!NTTP->isExpandedParameterPack()) {
        if (!NTTP->getType()->isDependentType()) {
          LV.merge(getLVForType(*NTTP->getType(), computation));
        }
        continue;
      }

      // Look at all the types in an expanded pack.
      for (unsigned i = 0, n = NTTP->getNumExpansionTypes(); i != n; ++i) {
        QualType type = NTTP->getExpansionType(i);
        if (!type->isDependentType())
          LV.merge(type->getLinkageAndVisibility());
      }
      continue;
    }

    // Template template parameters can be restricted by their
    // template parameters, recursively.
    const TemplateTemplateParmDecl *TTP = cast<TemplateTemplateParmDecl>(P);

    // Handle the non-pack case first.
    if (!TTP->isExpandedParameterPack()) {
      LV.merge(getLVForTemplateParameterList(TTP->getTemplateParameters(),
                                             computation));
      continue;
    }

    // Look at all expansions in an expanded pack.
    for (unsigned i = 0, n = TTP->getNumExpansionTemplateParameters();
           i != n; ++i) {
      LV.merge(getLVForTemplateParameterList(
          TTP->getExpansionTemplateParameters(i), computation));
    }
  }

  return LV;
}

/// getLVForDecl - Get the linkage and visibility for the given declaration.
static LinkageInfo getLVForDecl(const NamedDecl *D,
                                LVComputationKind computation);

static const Decl *getOutermostFuncOrBlockContext(const Decl *D) {
  const Decl *Ret = nullptr;
  const DeclContext *DC = D->getDeclContext();
  while (DC->getDeclKind() != Decl::TranslationUnit) {
    if (isa<FunctionDecl>(DC) || isa<BlockDecl>(DC))
      Ret = cast<Decl>(DC);
    DC = DC->getParent();
  }
  return Ret;
}

/// \brief Get the most restrictive linkage for the types and
/// declarations in the given template argument list.
///
/// Note that we don't take an LVComputationKind because we always
/// want to honor the visibility of template arguments in the same way.
static LinkageInfo getLVForTemplateArgumentList(ArrayRef<TemplateArgument> Args,
                                                LVComputationKind computation) {
  LinkageInfo LV;

  for (const TemplateArgument &Arg : Args) {
    switch (Arg.getKind()) {
    case TemplateArgument::Null:
    case TemplateArgument::Integral:
    case TemplateArgument::Expression:
      continue;

    case TemplateArgument::Type:
      LV.merge(getLVForType(*Arg.getAsType(), computation));
      continue;

    case TemplateArgument::Declaration:
      if (NamedDecl *ND = dyn_cast<NamedDecl>(Arg.getAsDecl())) {
        assert(!usesTypeVisibility(ND));
        LV.merge(getLVForDecl(ND, computation));
      }
      continue;

    case TemplateArgument::NullPtr:
      LV.merge(Arg.getNullPtrType()->getLinkageAndVisibility());
      continue;

    case TemplateArgument::Template:
    case TemplateArgument::TemplateExpansion:
      if (TemplateDecl *Template =
              Arg.getAsTemplateOrTemplatePattern().getAsTemplateDecl())
        LV.merge(getLVForDecl(Template, computation));
      continue;

    case TemplateArgument::Pack:
      LV.merge(getLVForTemplateArgumentList(Arg.getPackAsArray(), computation));
      continue;
    }
    llvm_unreachable("bad template argument kind");
  }

  return LV;
}

static LinkageInfo
getLVForTemplateArgumentList(const TemplateArgumentList &TArgs,
                             LVComputationKind computation) {
  return getLVForTemplateArgumentList(TArgs.asArray(), computation);
}

static bool shouldConsiderTemplateVisibility(const FunctionDecl *fn,
                        const FunctionTemplateSpecializationInfo *specInfo) {
  // Include visibility from the template parameters and arguments
  // only if this is not an explicit instantiation or specialization
  // with direct explicit visibility.  (Implicit instantiations won't
  // have a direct attribute.)
  if (!specInfo->isExplicitInstantiationOrSpecialization())
    return true;

  return !fn->hasAttr<VisibilityAttr>();
}

/// Merge in template-related linkage and visibility for the given
/// function template specialization.
///
/// We don't need a computation kind here because we can assume
/// LVForValue.
///
/// \param[out] LV the computation to use for the parent
static void
mergeTemplateLV(LinkageInfo &LV, const FunctionDecl *fn,
                const FunctionTemplateSpecializationInfo *specInfo,
                LVComputationKind computation) {
  bool considerVisibility =
    shouldConsiderTemplateVisibility(fn, specInfo);

  // Merge information from the template parameters.
  FunctionTemplateDecl *temp = specInfo->getTemplate();
  LinkageInfo tempLV =
    getLVForTemplateParameterList(temp->getTemplateParameters(), computation);
  LV.mergeMaybeWithVisibility(tempLV, considerVisibility);

  // Merge information from the template arguments.
  const TemplateArgumentList &templateArgs = *specInfo->TemplateArguments;
  LinkageInfo argsLV = getLVForTemplateArgumentList(templateArgs, computation);
  LV.mergeMaybeWithVisibility(argsLV, considerVisibility);
}

/// Does the given declaration have a direct visibility attribute
/// that would match the given rules?
static bool hasDirectVisibilityAttribute(const NamedDecl *D,
                                         LVComputationKind computation) {
  switch (computation) {
  case LVForType:
  case LVForExplicitType:
    if (D->hasAttr<TypeVisibilityAttr>())
      return true;
    // fallthrough
  case LVForValue:
  case LVForExplicitValue:
    if (D->hasAttr<VisibilityAttr>())
      return true;
    return false;
  case LVForLinkageOnly:
    return false;
  }
  llvm_unreachable("bad visibility computation kind");
}

/// Should we consider visibility associated with the template
/// arguments and parameters of the given class template specialization?
static bool shouldConsiderTemplateVisibility(
                                 const ClassTemplateSpecializationDecl *spec,
                                 LVComputationKind computation) {
  // Include visibility from the template parameters and arguments
  // only if this is not an explicit instantiation or specialization
  // with direct explicit visibility (and note that implicit
  // instantiations won't have a direct attribute).
  //
  // Furthermore, we want to ignore template parameters and arguments
  // for an explicit specialization when computing the visibility of a
  // member thereof with explicit visibility.
  //
  // This is a bit complex; let's unpack it.
  //
  // An explicit class specialization is an independent, top-level
  // declaration.  As such, if it or any of its members has an
  // explicit visibility attribute, that must directly express the
  // user's intent, and we should honor it.  The same logic applies to
  // an explicit instantiation of a member of such a thing.

  // Fast path: if this is not an explicit instantiation or
  // specialization, we always want to consider template-related
  // visibility restrictions.
  if (!spec->isExplicitInstantiationOrSpecialization())
    return true;

  // This is the 'member thereof' check.
  if (spec->isExplicitSpecialization() &&
      hasExplicitVisibilityAlready(computation))
    return false;

  return !hasDirectVisibilityAttribute(spec, computation);
}

/// Merge in template-related linkage and visibility for the given
/// class template specialization.
static void mergeTemplateLV(LinkageInfo &LV,
                            const ClassTemplateSpecializationDecl *spec,
                            LVComputationKind computation) {
  bool considerVisibility = shouldConsiderTemplateVisibility(spec, computation);

  // Merge information from the template parameters, but ignore
  // visibility if we're only considering template arguments.

  ClassTemplateDecl *temp = spec->getSpecializedTemplate();
  LinkageInfo tempLV =
    getLVForTemplateParameterList(temp->getTemplateParameters(), computation);
  LV.mergeMaybeWithVisibility(tempLV,
           considerVisibility && !hasExplicitVisibilityAlready(computation));

  // Merge information from the template arguments.  We ignore
  // template-argument visibility if we've got an explicit
  // instantiation with a visibility attribute.
  const TemplateArgumentList &templateArgs = spec->getTemplateArgs();
  LinkageInfo argsLV = getLVForTemplateArgumentList(templateArgs, computation);
  if (considerVisibility)
    LV.mergeVisibility(argsLV);
  LV.mergeExternalVisibility(argsLV);
}

/// Should we consider visibility associated with the template
/// arguments and parameters of the given variable template
/// specialization? As usual, follow class template specialization
/// logic up to initialization.
static bool shouldConsiderTemplateVisibility(
                                 const VarTemplateSpecializationDecl *spec,
                                 LVComputationKind computation) {
  // Include visibility from the template parameters and arguments
  // only if this is not an explicit instantiation or specialization
  // with direct explicit visibility (and note that implicit
  // instantiations won't have a direct attribute).
  if (!spec->isExplicitInstantiationOrSpecialization())
    return true;

  // An explicit variable specialization is an independent, top-level
  // declaration.  As such, if it has an explicit visibility attribute,
  // that must directly express the user's intent, and we should honor
  // it.
  if (spec->isExplicitSpecialization() &&
      hasExplicitVisibilityAlready(computation))
    return false;

  return !hasDirectVisibilityAttribute(spec, computation);
}

/// Merge in template-related linkage and visibility for the given
/// variable template specialization. As usual, follow class template
/// specialization logic up to initialization.
static void mergeTemplateLV(LinkageInfo &LV,
                            const VarTemplateSpecializationDecl *spec,
                            LVComputationKind computation) {
  bool considerVisibility = shouldConsiderTemplateVisibility(spec, computation);

  // Merge information from the template parameters, but ignore
  // visibility if we're only considering template arguments.

  VarTemplateDecl *temp = spec->getSpecializedTemplate();
  LinkageInfo tempLV =
    getLVForTemplateParameterList(temp->getTemplateParameters(), computation);
  LV.mergeMaybeWithVisibility(tempLV,
           considerVisibility && !hasExplicitVisibilityAlready(computation));

  // Merge information from the template arguments.  We ignore
  // template-argument visibility if we've got an explicit
  // instantiation with a visibility attribute.
  const TemplateArgumentList &templateArgs = spec->getTemplateArgs();
  LinkageInfo argsLV = getLVForTemplateArgumentList(templateArgs, computation);
  if (considerVisibility)
    LV.mergeVisibility(argsLV);
  LV.mergeExternalVisibility(argsLV);
}

static bool useInlineVisibilityHidden(const NamedDecl *D) {
  // FIXME: we should warn if -fvisibility-inlines-hidden is used with c.
  const LangOptions &Opts = D->getASTContext().getLangOpts();
  if (!Opts.CPlusPlus || !Opts.InlineVisibilityHidden)
    return false;

  const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
  if (!FD)
    return false;

  TemplateSpecializationKind TSK = TSK_Undeclared;
  if (FunctionTemplateSpecializationInfo *spec
      = FD->getTemplateSpecializationInfo()) {
    TSK = spec->getTemplateSpecializationKind();
  } else if (MemberSpecializationInfo *MSI =
             FD->getMemberSpecializationInfo()) {
    TSK = MSI->getTemplateSpecializationKind();
  }

  const FunctionDecl *Def = nullptr;
  // InlineVisibilityHidden only applies to definitions, and
  // isInlined() only gives meaningful answers on definitions
  // anyway.
  return TSK != TSK_ExplicitInstantiationDeclaration &&
    TSK != TSK_ExplicitInstantiationDefinition &&
    FD->hasBody(Def) && Def->isInlined() && !Def->hasAttr<GNUInlineAttr>();
}

template <typename T> static bool isFirstInExternCContext(T *D) {
  const T *First = D->getFirstDecl();
  return First->isInExternCContext();
}

static bool isSingleLineLanguageLinkage(const Decl &D) {
  if (const LinkageSpecDecl *SD = dyn_cast<LinkageSpecDecl>(D.getDeclContext()))
    if (!SD->hasBraces())
      return true;
  return false;
}

static LinkageInfo getLVForNamespaceScopeDecl(const NamedDecl *D,
                                              LVComputationKind computation) {
  assert(D->getDeclContext()->getRedeclContext()->isFileContext() &&
         "Not a name having namespace scope");
  ASTContext &Context = D->getASTContext();

  // C++ [basic.link]p3:
  //   A name having namespace scope (3.3.6) has internal linkage if it
  //   is the name of
  //     - an object, reference, function or function template that is
  //       explicitly declared static; or,
  // (This bullet corresponds to C99 6.2.2p3.)
  if (const VarDecl *Var = dyn_cast<VarDecl>(D)) {
    // Explicitly declared static.
    if (Var->getStorageClass() == SC_Static)
      return LinkageInfo::internal();

    // - a non-volatile object or reference that is explicitly declared const
    //   or constexpr and neither explicitly declared extern nor previously
    //   declared to have external linkage; or (there is no equivalent in C99)
    if (Context.getLangOpts().CPlusPlus &&
        Var->getType().isConstQualified() && 
        !Var->getType().isVolatileQualified()) {
      const VarDecl *PrevVar = Var->getPreviousDecl();
      if (PrevVar)
        return getLVForDecl(PrevVar, computation);

      if (Var->getStorageClass() != SC_Extern &&
          Var->getStorageClass() != SC_PrivateExtern &&
          !isSingleLineLanguageLinkage(*Var))
        return LinkageInfo::internal();
    }

    for (const VarDecl *PrevVar = Var->getPreviousDecl(); PrevVar;
         PrevVar = PrevVar->getPreviousDecl()) {
      if (PrevVar->getStorageClass() == SC_PrivateExtern &&
          Var->getStorageClass() == SC_None)
        return PrevVar->getLinkageAndVisibility();
      // Explicitly declared static.
      if (PrevVar->getStorageClass() == SC_Static)
        return LinkageInfo::internal();
    }
  } else if (const FunctionDecl *Function = D->getAsFunction()) {
    // C++ [temp]p4:
    //   A non-member function template can have internal linkage; any
    //   other template name shall have external linkage.

    // Explicitly declared static.
    if (Function->getCanonicalDecl()->getStorageClass() == SC_Static)
      return LinkageInfo(InternalLinkage, DefaultVisibility, false);
  } else if (const auto *IFD = dyn_cast<IndirectFieldDecl>(D)) {
    //   - a data member of an anonymous union.
    const VarDecl *VD = IFD->getVarDecl();
    assert(VD && "Expected a VarDecl in this IndirectFieldDecl!");
    return getLVForNamespaceScopeDecl(VD, computation);
  }
  assert(!isa<FieldDecl>(D) && "Didn't expect a FieldDecl!");

  if (D->isInAnonymousNamespace()) {
    const VarDecl *Var = dyn_cast<VarDecl>(D);
    const FunctionDecl *Func = dyn_cast<FunctionDecl>(D);
    if ((!Var || !isFirstInExternCContext(Var)) &&
        (!Func || !isFirstInExternCContext(Func)))
      return LinkageInfo::uniqueExternal();
  }

  // Set up the defaults.

  // C99 6.2.2p5:
  //   If the declaration of an identifier for an object has file
  //   scope and no storage-class specifier, its linkage is
  //   external.
  LinkageInfo LV;

  if (!hasExplicitVisibilityAlready(computation)) {
    if (Optional<Visibility> Vis = getExplicitVisibility(D, computation)) {
      LV.mergeVisibility(*Vis, true);
    } else {
      // If we're declared in a namespace with a visibility attribute,
      // use that namespace's visibility, and it still counts as explicit.
      for (const DeclContext *DC = D->getDeclContext();
           !isa<TranslationUnitDecl>(DC);
           DC = DC->getParent()) {
        const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(DC);
        if (!ND) continue;
        if (Optional<Visibility> Vis = getExplicitVisibility(ND, computation)) {
          LV.mergeVisibility(*Vis, true);
          break;
        }
      }
    }

    // Add in global settings if the above didn't give us direct visibility.
    if (!LV.isVisibilityExplicit()) {
      // Use global type/value visibility as appropriate.
      Visibility globalVisibility;
      if (computation == LVForValue) {
        globalVisibility = Context.getLangOpts().getValueVisibilityMode();
      } else {
        assert(computation == LVForType);
        globalVisibility = Context.getLangOpts().getTypeVisibilityMode();
      }
      LV.mergeVisibility(globalVisibility, /*explicit*/ false);

      // If we're paying attention to global visibility, apply
      // -finline-visibility-hidden if this is an inline method.
      if (useInlineVisibilityHidden(D))
        LV.mergeVisibility(HiddenVisibility, true);
    }
  }

  // C++ [basic.link]p4:

  //   A name having namespace scope has external linkage if it is the
  //   name of
  //
  //     - an object or reference, unless it has internal linkage; or
  if (const VarDecl *Var = dyn_cast<VarDecl>(D)) {
    // GCC applies the following optimization to variables and static
    // data members, but not to functions:
    //
    // Modify the variable's LV by the LV of its type unless this is
    // C or extern "C".  This follows from [basic.link]p9:
    //   A type without linkage shall not be used as the type of a
    //   variable or function with external linkage unless
    //    - the entity has C language linkage, or
    //    - the entity is declared within an unnamed namespace, or
    //    - the entity is not used or is defined in the same
    //      translation unit.
    // and [basic.link]p10:
    //   ...the types specified by all declarations referring to a
    //   given variable or function shall be identical...
    // C does not have an equivalent rule.
    //
    // Ignore this if we've got an explicit attribute;  the user
    // probably knows what they're doing.
    //
    // Note that we don't want to make the variable non-external
    // because of this, but unique-external linkage suits us.
    if (Context.getLangOpts().CPlusPlus && !isFirstInExternCContext(Var)) {
      LinkageInfo TypeLV = getLVForType(*Var->getType(), computation);
      if (TypeLV.getLinkage() != ExternalLinkage)
        return LinkageInfo::uniqueExternal();
      if (!LV.isVisibilityExplicit())
        LV.mergeVisibility(TypeLV);
    }

    if (Var->getStorageClass() == SC_PrivateExtern)
      LV.mergeVisibility(HiddenVisibility, true);

    // Note that Sema::MergeVarDecl already takes care of implementing
    // C99 6.2.2p4 and propagating the visibility attribute, so we don't have
    // to do it here.

    // As per function and class template specializations (below),
    // consider LV for the template and template arguments.  We're at file
    // scope, so we do not need to worry about nested specializations.
    if (const VarTemplateSpecializationDecl *spec
              = dyn_cast<VarTemplateSpecializationDecl>(Var)) {
      mergeTemplateLV(LV, spec, computation);
    }

  //     - a function, unless it has internal linkage; or
  } else if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) {
    // In theory, we can modify the function's LV by the LV of its
    // type unless it has C linkage (see comment above about variables
    // for justification).  In practice, GCC doesn't do this, so it's
    // just too painful to make work.

    if (Function->getStorageClass() == SC_PrivateExtern)
      LV.mergeVisibility(HiddenVisibility, true);

    // Note that Sema::MergeCompatibleFunctionDecls already takes care of
    // merging storage classes and visibility attributes, so we don't have to
    // look at previous decls in here.

    // In C++, then if the type of the function uses a type with
    // unique-external linkage, it's not legally usable from outside
    // this translation unit.  However, we should use the C linkage
    // rules instead for extern "C" declarations.
    if (Context.getLangOpts().CPlusPlus &&
        !Function->isInExternCContext()) {
      // Only look at the type-as-written. If this function has an auto-deduced
      // return type, we can't compute the linkage of that type because it could
      // require looking at the linkage of this function, and we don't need this
      // for correctness because the type is not part of the function's
      // signature.
      // FIXME: This is a hack. We should be able to solve this circularity and 
      // the one in getLVForClassMember for Functions some other way.
      QualType TypeAsWritten = Function->getType();
      if (TypeSourceInfo *TSI = Function->getTypeSourceInfo())
        TypeAsWritten = TSI->getType();
      if (TypeAsWritten->getLinkage() == UniqueExternalLinkage)
        return LinkageInfo::uniqueExternal();
    }

    // Consider LV from the template and the template arguments.
    // We're at file scope, so we do not need to worry about nested
    // specializations.
    if (FunctionTemplateSpecializationInfo *specInfo
                               = Function->getTemplateSpecializationInfo()) {
      mergeTemplateLV(LV, Function, specInfo, computation);
    }

  //     - a named class (Clause 9), or an unnamed class defined in a
  //       typedef declaration in which the class has the typedef name
  //       for linkage purposes (7.1.3); or
  //     - a named enumeration (7.2), or an unnamed enumeration
  //       defined in a typedef declaration in which the enumeration
  //       has the typedef name for linkage purposes (7.1.3); or
  } else if (const TagDecl *Tag = dyn_cast<TagDecl>(D)) {
    // Unnamed tags have no linkage.
    if (!Tag->hasNameForLinkage())
      return LinkageInfo::none();

    // If this is a class template specialization, consider the
    // linkage of the template and template arguments.  We're at file
    // scope, so we do not need to worry about nested specializations.
    if (const ClassTemplateSpecializationDecl *spec
          = dyn_cast<ClassTemplateSpecializationDecl>(Tag)) {
      mergeTemplateLV(LV, spec, computation);
    }

  //     - an enumerator belonging to an enumeration with external linkage;
  } else if (isa<EnumConstantDecl>(D)) {
    LinkageInfo EnumLV = getLVForDecl(cast<NamedDecl>(D->getDeclContext()),
                                      computation);
    if (!isExternalFormalLinkage(EnumLV.getLinkage()))
      return LinkageInfo::none();
    LV.merge(EnumLV);

  //     - a template, unless it is a function template that has
  //       internal linkage (Clause 14);
  } else if (const TemplateDecl *temp = dyn_cast<TemplateDecl>(D)) {
    bool considerVisibility = !hasExplicitVisibilityAlready(computation);
    LinkageInfo tempLV =
      getLVForTemplateParameterList(temp->getTemplateParameters(), computation);
    LV.mergeMaybeWithVisibility(tempLV, considerVisibility);

  //     - a namespace (7.3), unless it is declared within an unnamed
  //       namespace.
  } else if (isa<NamespaceDecl>(D) && !D->isInAnonymousNamespace()) {
    return LV;

  // By extension, we assign external linkage to Objective-C
  // interfaces.
  } else if (isa<ObjCInterfaceDecl>(D)) {
    // fallout

  // Everything not covered here has no linkage.
  } else {
    // FIXME: A typedef declaration has linkage if it gives a type a name for
    // linkage purposes.
    return LinkageInfo::none();
  }

  // If we ended up with non-external linkage, visibility should
  // always be default.
  if (LV.getLinkage() != ExternalLinkage)
    return LinkageInfo(LV.getLinkage(), DefaultVisibility, false);

  return LV;
}

static LinkageInfo getLVForClassMember(const NamedDecl *D,
                                       LVComputationKind computation) {
  // Only certain class members have linkage.  Note that fields don't
  // really have linkage, but it's convenient to say they do for the
  // purposes of calculating linkage of pointer-to-data-member
  // template arguments.
  //
  // Templates also don't officially have linkage, but since we ignore
  // the C++ standard and look at template arguments when determining
  // linkage and visibility of a template specialization, we might hit
  // a template template argument that way. If we do, we need to
  // consider its linkage.
  if (!(isa<CXXMethodDecl>(D) ||
        isa<VarDecl>(D) ||
        isa<FieldDecl>(D) ||
        isa<IndirectFieldDecl>(D) ||
        isa<TagDecl>(D) ||
        isa<TemplateDecl>(D)))
    return LinkageInfo::none();

  LinkageInfo LV;

  // If we have an explicit visibility attribute, merge that in.
  if (!hasExplicitVisibilityAlready(computation)) {
    if (Optional<Visibility> Vis = getExplicitVisibility(D, computation))
      LV.mergeVisibility(*Vis, true);
    // If we're paying attention to global visibility, apply
    // -finline-visibility-hidden if this is an inline method.
    //
    // Note that we do this before merging information about
    // the class visibility.
    if (!LV.isVisibilityExplicit() && useInlineVisibilityHidden(D))
      LV.mergeVisibility(HiddenVisibility, true);
  }

  // If this class member has an explicit visibility attribute, the only
  // thing that can change its visibility is the template arguments, so
  // only look for them when processing the class.
  LVComputationKind classComputation = computation;
  if (LV.isVisibilityExplicit())
    classComputation = withExplicitVisibilityAlready(computation);

  LinkageInfo classLV =
    getLVForDecl(cast<RecordDecl>(D->getDeclContext()), classComputation);
  // If the class already has unique-external linkage, we can't improve.
  if (classLV.getLinkage() == UniqueExternalLinkage)
    return LinkageInfo::uniqueExternal();

  if (!isExternallyVisible(classLV.getLinkage()))
    return LinkageInfo::none();


  // Otherwise, don't merge in classLV yet, because in certain cases
  // we need to completely ignore the visibility from it.

  // Specifically, if this decl exists and has an explicit attribute.
  const NamedDecl *explicitSpecSuppressor = nullptr;

  if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
    // If the type of the function uses a type with unique-external
    // linkage, it's not legally usable from outside this translation unit.
    // But only look at the type-as-written. If this function has an
    // auto-deduced return type, we can't compute the linkage of that type
    // because it could require looking at the linkage of this function, and we
    // don't need this for correctness because the type is not part of the
    // function's signature.
    // FIXME: This is a hack. We should be able to solve this circularity and
    // the one in getLVForNamespaceScopeDecl for Functions some other way.
    {
      QualType TypeAsWritten = MD->getType();
      if (TypeSourceInfo *TSI = MD->getTypeSourceInfo())
        TypeAsWritten = TSI->getType();
      if (TypeAsWritten->getLinkage() == UniqueExternalLinkage)
        return LinkageInfo::uniqueExternal();
    }
    // If this is a method template specialization, use the linkage for
    // the template parameters and arguments.
    if (FunctionTemplateSpecializationInfo *spec
           = MD->getTemplateSpecializationInfo()) {
      mergeTemplateLV(LV, MD, spec, computation);
      if (spec->isExplicitSpecialization()) {
        explicitSpecSuppressor = MD;
      } else if (isExplicitMemberSpecialization(spec->getTemplate())) {
        explicitSpecSuppressor = spec->getTemplate()->getTemplatedDecl();
      }
    } else if (isExplicitMemberSpecialization(MD)) {
      explicitSpecSuppressor = MD;
    }

  } else if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
    if (const ClassTemplateSpecializationDecl *spec
        = dyn_cast<ClassTemplateSpecializationDecl>(RD)) {
      mergeTemplateLV(LV, spec, computation);
      if (spec->isExplicitSpecialization()) {
        explicitSpecSuppressor = spec;
      } else {
        const ClassTemplateDecl *temp = spec->getSpecializedTemplate();
        if (isExplicitMemberSpecialization(temp)) {
          explicitSpecSuppressor = temp->getTemplatedDecl();
        }
      }
    } else if (isExplicitMemberSpecialization(RD)) {
      explicitSpecSuppressor = RD;
    }

  // Static data members.
  } else if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
    if (const VarTemplateSpecializationDecl *spec
        = dyn_cast<VarTemplateSpecializationDecl>(VD))
      mergeTemplateLV(LV, spec, computation);

    // Modify the variable's linkage by its type, but ignore the
    // type's visibility unless it's a definition.
    LinkageInfo typeLV = getLVForType(*VD->getType(), computation);
    if (!LV.isVisibilityExplicit() && !classLV.isVisibilityExplicit())
      LV.mergeVisibility(typeLV);
    LV.mergeExternalVisibility(typeLV);

    if (isExplicitMemberSpecialization(VD)) {
      explicitSpecSuppressor = VD;
    }

  // Template members.
  } else if (const TemplateDecl *temp = dyn_cast<TemplateDecl>(D)) {
    bool considerVisibility =
      (!LV.isVisibilityExplicit() &&
       !classLV.isVisibilityExplicit() &&
       !hasExplicitVisibilityAlready(computation));
    LinkageInfo tempLV =
      getLVForTemplateParameterList(temp->getTemplateParameters(), computation);
    LV.mergeMaybeWithVisibility(tempLV, considerVisibility);

    if (const RedeclarableTemplateDecl *redeclTemp =
          dyn_cast<RedeclarableTemplateDecl>(temp)) {
      if (isExplicitMemberSpecialization(redeclTemp)) {
        explicitSpecSuppressor = temp->getTemplatedDecl();
      }
    }
  }

  // We should never be looking for an attribute directly on a template.
  assert(!explicitSpecSuppressor || !isa<TemplateDecl>(explicitSpecSuppressor));

  // If this member is an explicit member specialization, and it has
  // an explicit attribute, ignore visibility from the parent.
  bool considerClassVisibility = true;
  if (explicitSpecSuppressor &&
      // optimization: hasDVA() is true only with explicit visibility.
      LV.isVisibilityExplicit() &&
      classLV.getVisibility() != DefaultVisibility &&
      hasDirectVisibilityAttribute(explicitSpecSuppressor, computation)) {
    considerClassVisibility = false;
  }

  // Finally, merge in information from the class.
  LV.mergeMaybeWithVisibility(classLV, considerClassVisibility);
  return LV;
}

void NamedDecl::anchor() { }

static LinkageInfo computeLVForDecl(const NamedDecl *D,
                                    LVComputationKind computation);

bool NamedDecl::isLinkageValid() const {
  if (!hasCachedLinkage())
    return true;

  return computeLVForDecl(this, LVForLinkageOnly).getLinkage() ==
         getCachedLinkage();
}

ObjCStringFormatFamily NamedDecl::getObjCFStringFormattingFamily() const {
  StringRef name = getName();
  if (name.empty()) return SFF_None;
  
  if (name.front() == 'C')
    if (name == "CFStringCreateWithFormat" ||
        name == "CFStringCreateWithFormatAndArguments" ||
        name == "CFStringAppendFormat" ||
        name == "CFStringAppendFormatAndArguments")
      return SFF_CFString;
  return SFF_None;
}

Linkage NamedDecl::getLinkageInternal() const {
  // We don't care about visibility here, so ask for the cheapest
  // possible visibility analysis.
  return getLVForDecl(this, LVForLinkageOnly).getLinkage();
}

LinkageInfo NamedDecl::getLinkageAndVisibility() const {
  LVComputationKind computation =
    (usesTypeVisibility(this) ? LVForType : LVForValue);
  return getLVForDecl(this, computation);
}

static Optional<Visibility>
getExplicitVisibilityAux(const NamedDecl *ND,
                         NamedDecl::ExplicitVisibilityKind kind,
                         bool IsMostRecent) {
  assert(!IsMostRecent || ND == ND->getMostRecentDecl());

  // Check the declaration itself first.
  if (Optional<Visibility> V = getVisibilityOf(ND, kind))
    return V;

  // If this is a member class of a specialization of a class template
  // and the corresponding decl has explicit visibility, use that.
  if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(ND)) {
    CXXRecordDecl *InstantiatedFrom = RD->getInstantiatedFromMemberClass();
    if (InstantiatedFrom)
      return getVisibilityOf(InstantiatedFrom, kind);
  }

  // If there wasn't explicit visibility there, and this is a
  // specialization of a class template, check for visibility
  // on the pattern.
  if (const ClassTemplateSpecializationDecl *spec
        = dyn_cast<ClassTemplateSpecializationDecl>(ND))
    return getVisibilityOf(spec->getSpecializedTemplate()->getTemplatedDecl(),
                           kind);

  // Use the most recent declaration.
  if (!IsMostRecent && !isa<NamespaceDecl>(ND)) {
    const NamedDecl *MostRecent = ND->getMostRecentDecl();
    if (MostRecent != ND)
      return getExplicitVisibilityAux(MostRecent, kind, true);
  }

  if (const VarDecl *Var = dyn_cast<VarDecl>(ND)) {
    if (Var->isStaticDataMember()) {
      VarDecl *InstantiatedFrom = Var->getInstantiatedFromStaticDataMember();
      if (InstantiatedFrom)
        return getVisibilityOf(InstantiatedFrom, kind);
    }

    if (const auto *VTSD = dyn_cast<VarTemplateSpecializationDecl>(Var))
      return getVisibilityOf(VTSD->getSpecializedTemplate()->getTemplatedDecl(),
                             kind);

    return None;
  }
  // Also handle function template specializations.
  if (const FunctionDecl *fn = dyn_cast<FunctionDecl>(ND)) {
    // If the function is a specialization of a template with an
    // explicit visibility attribute, use that.
    if (FunctionTemplateSpecializationInfo *templateInfo
          = fn->getTemplateSpecializationInfo())
      return getVisibilityOf(templateInfo->getTemplate()->getTemplatedDecl(),
                             kind);

    // If the function is a member of a specialization of a class template
    // and the corresponding decl has explicit visibility, use that.
    FunctionDecl *InstantiatedFrom = fn->getInstantiatedFromMemberFunction();
    if (InstantiatedFrom)
      return getVisibilityOf(InstantiatedFrom, kind);

    return None;
  }

  // The visibility of a template is stored in the templated decl.
  if (const TemplateDecl *TD = dyn_cast<TemplateDecl>(ND))
    return getVisibilityOf(TD->getTemplatedDecl(), kind);

  return None;
}

Optional<Visibility>
NamedDecl::getExplicitVisibility(ExplicitVisibilityKind kind) const {
  return getExplicitVisibilityAux(this, kind, false);
}

static LinkageInfo getLVForClosure(const DeclContext *DC, Decl *ContextDecl,
                                   LVComputationKind computation) {
  // This lambda has its linkage/visibility determined by its owner.
  if (ContextDecl) {
    if (isa<ParmVarDecl>(ContextDecl))
      DC = ContextDecl->getDeclContext()->getRedeclContext();
    else
      return getLVForDecl(cast<NamedDecl>(ContextDecl), computation);
  }

  if (const NamedDecl *ND = dyn_cast<NamedDecl>(DC))
    return getLVForDecl(ND, computation);

  return LinkageInfo::external();
}

static LinkageInfo getLVForLocalDecl(const NamedDecl *D,
                                     LVComputationKind computation) {
  if (const FunctionDecl *Function = dyn_cast<FunctionDecl>(D)) {
    if (Function->isInAnonymousNamespace() &&
        !Function->isInExternCContext())
      return LinkageInfo::uniqueExternal();

    // This is a "void f();" which got merged with a file static.
    if (Function->getCanonicalDecl()->getStorageClass() == SC_Static)
      return LinkageInfo::internal();

    LinkageInfo LV;
    if (!hasExplicitVisibilityAlready(computation)) {
      if (Optional<Visibility> Vis =
              getExplicitVisibility(Function, computation))
        LV.mergeVisibility(*Vis, true);
    }

    // Note that Sema::MergeCompatibleFunctionDecls already takes care of
    // merging storage classes and visibility attributes, so we don't have to
    // look at previous decls in here.

    return LV;
  }

  if (const VarDecl *Var = dyn_cast<VarDecl>(D)) {
    if (Var->hasExternalStorage()) {
      if (Var->isInAnonymousNamespace() && !Var->isInExternCContext())
        return LinkageInfo::uniqueExternal();

      LinkageInfo LV;
      if (Var->getStorageClass() == SC_PrivateExtern)
        LV.mergeVisibility(HiddenVisibility, true);
      else if (!hasExplicitVisibilityAlready(computation)) {
        if (Optional<Visibility> Vis = getExplicitVisibility(Var, computation))
          LV.mergeVisibility(*Vis, true);
      }

      if (const VarDecl *Prev = Var->getPreviousDecl()) {
        LinkageInfo PrevLV = getLVForDecl(Prev, computation);
        if (PrevLV.getLinkage())
          LV.setLinkage(PrevLV.getLinkage());
        LV.mergeVisibility(PrevLV);
      }

      return LV;
    }

    if (!Var->isStaticLocal())
      return LinkageInfo::none();
  }

  ASTContext &Context = D->getASTContext();
  if (!Context.getLangOpts().CPlusPlus)
    return LinkageInfo::none();

  const Decl *OuterD = getOutermostFuncOrBlockContext(D);
  if (!OuterD)
    return LinkageInfo::none();

  LinkageInfo LV;
  if (const BlockDecl *BD = dyn_cast<BlockDecl>(OuterD)) {
    if (!BD->getBlockManglingNumber())
      return LinkageInfo::none();

    LV = getLVForClosure(BD->getDeclContext()->getRedeclContext(),
                         BD->getBlockManglingContextDecl(), computation);
  } else {
    const FunctionDecl *FD = cast<FunctionDecl>(OuterD);
    if (!FD->isInlined() &&
        !isTemplateInstantiation(FD->getTemplateSpecializationKind()))
      return LinkageInfo::none();

    LV = getLVForDecl(FD, computation);
  }
  if (!isExternallyVisible(LV.getLinkage()))
    return LinkageInfo::none();
  return LinkageInfo(VisibleNoLinkage, LV.getVisibility(),
                     LV.isVisibilityExplicit());
}

static inline const CXXRecordDecl*
getOutermostEnclosingLambda(const CXXRecordDecl *Record) {
  const CXXRecordDecl *Ret = Record;
  while (Record && Record->isLambda()) {
    Ret = Record;
    if (!Record->getParent()) break;
    // Get the Containing Class of this Lambda Class
    Record = dyn_cast_or_null<CXXRecordDecl>(
      Record->getParent()->getParent());
  }
  return Ret;
}

static LinkageInfo computeLVForDecl(const NamedDecl *D,
                                    LVComputationKind computation) {
  // Objective-C: treat all Objective-C declarations as having external
  // linkage.
  switch (D->getKind()) {
    default:
      break;
    case Decl::ParmVar:
      return LinkageInfo::none();
    case Decl::TemplateTemplateParm: // count these as external
    case Decl::NonTypeTemplateParm:
    case Decl::ObjCAtDefsField:
    case Decl::ObjCCategory:
    case Decl::ObjCCategoryImpl:
    case Decl::ObjCCompatibleAlias:
    case Decl::ObjCImplementation:
    case Decl::ObjCMethod:
    case Decl::ObjCProperty:
    case Decl::ObjCPropertyImpl:
    case Decl::ObjCProtocol:
      return LinkageInfo::external();
      
    case Decl::CXXRecord: {
      const CXXRecordDecl *Record = cast<CXXRecordDecl>(D);
      if (Record->isLambda()) {
        if (!Record->getLambdaManglingNumber()) {
          // This lambda has no mangling number, so it's internal.
          return LinkageInfo::internal();
        }

        // This lambda has its linkage/visibility determined:
        //  - either by the outermost lambda if that lambda has no mangling 
        //    number. 
        //  - or by the parent of the outer most lambda
        // This prevents infinite recursion in settings such as nested lambdas 
        // used in NSDMI's, for e.g. 
        //  struct L {
        //    int t{};
        //    int t2 = ([](int a) { return [](int b) { return b; };})(t)(t);    
        //  };
        const CXXRecordDecl *OuterMostLambda = 
            getOutermostEnclosingLambda(Record);
        if (!OuterMostLambda->getLambdaManglingNumber())
          return LinkageInfo::internal();
        
        return getLVForClosure(
                  OuterMostLambda->getDeclContext()->getRedeclContext(),
                  OuterMostLambda->getLambdaContextDecl(), computation);
      }
      
      break;
    }
  }

  // Handle linkage for namespace-scope names.
  if (D->getDeclContext()->getRedeclContext()->isFileContext())
    return getLVForNamespaceScopeDecl(D, computation);
  
  // C++ [basic.link]p5:
  //   In addition, a member function, static data member, a named
  //   class or enumeration of class scope, or an unnamed class or
  //   enumeration defined in a class-scope typedef declaration such
  //   that the class or enumeration has the typedef name for linkage
  //   purposes (7.1.3), has external linkage if the name of the class
  //   has external linkage.
  if (D->getDeclContext()->isRecord())
    return getLVForClassMember(D, computation);

  // C++ [basic.link]p6:
  //   The name of a function declared in block scope and the name of
  //   an object declared by a block scope extern declaration have
  //   linkage. If there is a visible declaration of an entity with
  //   linkage having the same name and type, ignoring entities
  //   declared outside the innermost enclosing namespace scope, the
  //   block scope declaration declares that same entity and receives
  //   the linkage of the previous declaration. If there is more than
  //   one such matching entity, the program is ill-formed. Otherwise,
  //   if no matching entity is found, the block scope entity receives
  //   external linkage.
  if (D->getDeclContext()->isFunctionOrMethod())
    return getLVForLocalDecl(D, computation);

  // C++ [basic.link]p6:
  //   Names not covered by these rules have no linkage.
  return LinkageInfo::none();
}

namespace clang {
class LinkageComputer {
public:
  static LinkageInfo getLVForDecl(const NamedDecl *D,
                                  LVComputationKind computation) {
    if (computation == LVForLinkageOnly && D->hasCachedLinkage())
      return LinkageInfo(D->getCachedLinkage(), DefaultVisibility, false);

    LinkageInfo LV = computeLVForDecl(D, computation);
    if (D->hasCachedLinkage())
      assert(D->getCachedLinkage() == LV.getLinkage());

    D->setCachedLinkage(LV.getLinkage());

#ifndef NDEBUG
    // In C (because of gnu inline) and in c++ with microsoft extensions an
    // static can follow an extern, so we can have two decls with different
    // linkages.
    const LangOptions &Opts = D->getASTContext().getLangOpts();
    if (!Opts.CPlusPlus || Opts.MicrosoftExt)
      return LV;

    // We have just computed the linkage for this decl. By induction we know
    // that all other computed linkages match, check that the one we just
    // computed also does.
    NamedDecl *Old = nullptr;
    for (auto I : D->redecls()) {
      NamedDecl *T = cast<NamedDecl>(I);
      if (T == D)
        continue;
      if (!T->isInvalidDecl() && T->hasCachedLinkage()) {
        Old = T;
        break;
      }
    }
    assert(!Old || Old->getCachedLinkage() == D->getCachedLinkage());
#endif

    return LV;
  }
};
}

static LinkageInfo getLVForDecl(const NamedDecl *D,
                                LVComputationKind computation) {
  return clang::LinkageComputer::getLVForDecl(D, computation);
}

std::string NamedDecl::getQualifiedNameAsString() const {
  std::string QualName;
  llvm::raw_string_ostream OS(QualName);
  printQualifiedName(OS, getASTContext().getPrintingPolicy());
  return OS.str();
}

void NamedDecl::printQualifiedName(raw_ostream &OS) const {
  printQualifiedName(OS, getASTContext().getPrintingPolicy());
}

void NamedDecl::printQualifiedName(raw_ostream &OS,
                                   const PrintingPolicy &P) const {
  const DeclContext *Ctx = getDeclContext();

  if (Ctx->isFunctionOrMethod()) {
    printName(OS);
    return;
  }

  typedef SmallVector<const DeclContext *, 8> ContextsTy;
  ContextsTy Contexts;

  // Collect contexts.
  while (Ctx && isa<NamedDecl>(Ctx)) {
    Contexts.push_back(Ctx);
    Ctx = Ctx->getParent();
  }

  for (ContextsTy::reverse_iterator I = Contexts.rbegin(), E = Contexts.rend();
       I != E; ++I) {
    if (const ClassTemplateSpecializationDecl *Spec
          = dyn_cast<ClassTemplateSpecializationDecl>(*I)) {
      OS << Spec->getName();
      const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
      TemplateSpecializationType::PrintTemplateArgumentList(OS,
                                                            TemplateArgs.data(),
                                                            TemplateArgs.size(),
                                                            P);
    } else if (const NamespaceDecl *ND = dyn_cast<NamespaceDecl>(*I)) {
      if (P.SuppressUnwrittenScope &&
          (ND->isAnonymousNamespace() || ND->isInline()))
        continue;
      if (ND->isAnonymousNamespace())
        OS << "(anonymous namespace)";
      else
        OS << *ND;
    } else if (const RecordDecl *RD = dyn_cast<RecordDecl>(*I)) {
      if (!RD->getIdentifier())
        OS << "(anonymous " << RD->getKindName() << ')';
      else
        OS << *RD;
    } else if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) {
      const FunctionProtoType *FT = nullptr;
      if (FD->hasWrittenPrototype())
        FT = dyn_cast<FunctionProtoType>(FD->getType()->castAs<FunctionType>());

      OS << *FD << '(';
      if (FT) {
        unsigned NumParams = FD->getNumParams();
        for (unsigned i = 0; i < NumParams; ++i) {
          if (i)
            OS << ", ";
          OS << FD->getParamDecl(i)->getType().stream(P);
        }

        if (FT->isVariadic()) {
          if (NumParams > 0)
            OS << ", ";
          OS << "...";
        }
      }
      OS << ')';
    } else {
      OS << *cast<NamedDecl>(*I);
    }
    OS << "::";
  }

  if (getDeclName())
    OS << *this;
  else
    OS << "(anonymous)";
}

void NamedDecl::getNameForDiagnostic(raw_ostream &OS,
                                     const PrintingPolicy &Policy,
                                     bool Qualified) const {
  if (Qualified)
    printQualifiedName(OS, Policy);
  else
    printName(OS);
}

static bool isKindReplaceableBy(Decl::Kind OldK, Decl::Kind NewK) {
  // For method declarations, we never replace.
  if (ObjCMethodDecl::classofKind(NewK))
    return false;

  if (OldK == NewK)
    return true;

  // A compatibility alias for a class can be replaced by an interface.
  if (ObjCCompatibleAliasDecl::classofKind(OldK) &&
      ObjCInterfaceDecl::classofKind(NewK))
    return true;

  // A typedef-declaration, alias-declaration, or Objective-C class declaration
  // can replace another declaration of the same type. Semantic analysis checks
  // that we have matching types.
  if ((TypedefNameDecl::classofKind(OldK) ||
       ObjCInterfaceDecl::classofKind(OldK)) &&
      (TypedefNameDecl::classofKind(NewK) ||
       ObjCInterfaceDecl::classofKind(NewK)))
    return true;

  // Otherwise, a kind mismatch implies that the declaration is not replaced.
  return false;
}

template<typename T> static bool isRedeclarableImpl(Redeclarable<T> *) {
  return true;
}
static bool isRedeclarableImpl(...) { return false; }
static bool isRedeclarable(Decl::Kind K) {
  switch (K) {
#define DECL(Type, Base) \
  case Decl::Type: \
    return isRedeclarableImpl((Type##Decl *)nullptr);
#define ABSTRACT_DECL(DECL)
#include "clang/AST/DeclNodes.inc"
  }
  llvm_unreachable("unknown decl kind");
}

bool NamedDecl::declarationReplaces(NamedDecl *OldD, bool IsKnownNewer) const {
  assert(getDeclName() == OldD->getDeclName() && "Declaration name mismatch");

  // Never replace one imported declaration with another; we need both results
  // when re-exporting.
  if (OldD->isFromASTFile() && isFromASTFile())
    return false;

  if (!isKindReplaceableBy(OldD->getKind(), getKind()))
    return false;

  // Inline namespaces can give us two declarations with the same
  // name and kind in the same scope but different contexts; we should
  // keep both declarations in this case.
  if (!this->getDeclContext()->getRedeclContext()->Equals(
          OldD->getDeclContext()->getRedeclContext()))
    return false;

  if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(this))
    // For function declarations, we keep track of redeclarations.
    // FIXME: This returns false for functions that should in fact be replaced.
    // Instead, perform some kind of type check?
    if (FD->getPreviousDecl() != OldD)
      return false;

  // For function templates, the underlying function declarations are linked.
  if (const FunctionTemplateDecl *FunctionTemplate =
          dyn_cast<FunctionTemplateDecl>(this))
    return FunctionTemplate->getTemplatedDecl()->declarationReplaces(
        cast<FunctionTemplateDecl>(OldD)->getTemplatedDecl());

  // Using shadow declarations can be overloaded on their target declarations
  // if they introduce functions.
  // FIXME: If our target replaces the old target, can we replace the old
  //        shadow declaration?
  if (auto *USD = dyn_cast<UsingShadowDecl>(this))
    if (USD->getTargetDecl() != cast<UsingShadowDecl>(OldD)->getTargetDecl())
      return false;

  // Using declarations can be overloaded if they introduce functions.
  if (auto *UD = dyn_cast<UsingDecl>(this)) {
    ASTContext &Context = getASTContext();
    return Context.getCanonicalNestedNameSpecifier(UD->getQualifier()) ==
           Context.getCanonicalNestedNameSpecifier(
               cast<UsingDecl>(OldD)->getQualifier());
  }
  if (auto *UUVD = dyn_cast<UnresolvedUsingValueDecl>(this)) {
    ASTContext &Context = getASTContext();
    return Context.getCanonicalNestedNameSpecifier(UUVD->getQualifier()) ==
           Context.getCanonicalNestedNameSpecifier(
                        cast<UnresolvedUsingValueDecl>(OldD)->getQualifier());
  }

  // UsingDirectiveDecl's are not really NamedDecl's, and all have same name.
  // We want to keep it, unless it nominates same namespace.
  if (auto *UD = dyn_cast<UsingDirectiveDecl>(this))
    return UD->getNominatedNamespace()->getOriginalNamespace() ==
           cast<UsingDirectiveDecl>(OldD)->getNominatedNamespace()
               ->getOriginalNamespace();

  if (!IsKnownNewer && isRedeclarable(getKind())) {
    // Check whether this is actually newer than OldD. We want to keep the
    // newer declaration. This loop will usually only iterate once, because
    // OldD is usually the previous declaration.
    for (auto D : redecls()) {
      if (D == OldD)
        break;

      // If we reach the canonical declaration, then OldD is not actually older
      // than this one.
      //
      // FIXME: In this case, we should not add this decl to the lookup table.
      if (D->isCanonicalDecl())
        return false;
    }
  }

  // It's a newer declaration of the same kind of declaration in the same scope,
  // and not an overload: we want this decl instead of the existing one.
  return true;
}

bool NamedDecl::hasLinkage() const {
  return getFormalLinkage() != NoLinkage;
}

NamedDecl *NamedDecl::getUnderlyingDeclImpl() {
  NamedDecl *ND = this;
  while (UsingShadowDecl *UD = dyn_cast<UsingShadowDecl>(ND))
    ND = UD->getTargetDecl();

  if (ObjCCompatibleAliasDecl *AD = dyn_cast<ObjCCompatibleAliasDecl>(ND))
    return AD->getClassInterface();

  return ND;
}

bool NamedDecl::isCXXInstanceMember() const {
  if (!isCXXClassMember())
    return false;
  
  const NamedDecl *D = this;
  if (isa<UsingShadowDecl>(D))
    D = cast<UsingShadowDecl>(D)->getTargetDecl();

  if (isa<FieldDecl>(D) || isa<IndirectFieldDecl>(D) || isa<MSPropertyDecl>(D))
    return true;
  if (const CXXMethodDecl *MD =
          dyn_cast_or_null<CXXMethodDecl>(D->getAsFunction()))
    return MD->isInstance();
  return false;
}

//===----------------------------------------------------------------------===//
// DeclaratorDecl Implementation
//===----------------------------------------------------------------------===//

template <typename DeclT>
static SourceLocation getTemplateOrInnerLocStart(const DeclT *decl) {
  if (decl->getNumTemplateParameterLists() > 0)
    return decl->getTemplateParameterList(0)->getTemplateLoc();
  else
    return decl->getInnerLocStart();
}

SourceLocation DeclaratorDecl::getTypeSpecStartLoc() const {
  TypeSourceInfo *TSI = getTypeSourceInfo();
  if (TSI) return TSI->getTypeLoc().getBeginLoc();
  return SourceLocation();
}

void DeclaratorDecl::setQualifierInfo(NestedNameSpecifierLoc QualifierLoc) {
  if (QualifierLoc) {
    // Make sure the extended decl info is allocated.
    if (!hasExtInfo()) {
      // Save (non-extended) type source info pointer.
      TypeSourceInfo *savedTInfo = DeclInfo.get<TypeSourceInfo*>();
      // Allocate external info struct.
      DeclInfo = new (getASTContext()) ExtInfo;
      // Restore savedTInfo into (extended) decl info.
      getExtInfo()->TInfo = savedTInfo;
    }
    // Set qualifier info.
    getExtInfo()->QualifierLoc = QualifierLoc;
  } else {
    // Here Qualifier == 0, i.e., we are removing the qualifier (if any).
    if (hasExtInfo()) {
      if (getExtInfo()->NumTemplParamLists == 0) {
        // Save type source info pointer.
        TypeSourceInfo *savedTInfo = getExtInfo()->TInfo;
        // Deallocate the extended decl info.
        getASTContext().Deallocate(getExtInfo());
        // Restore savedTInfo into (non-extended) decl info.
        DeclInfo = savedTInfo;
      }
      else
        getExtInfo()->QualifierLoc = QualifierLoc;
    }
  }
}

void
DeclaratorDecl::setTemplateParameterListsInfo(ASTContext &Context,
                                              unsigned NumTPLists,
                                              TemplateParameterList **TPLists) {
  assert(NumTPLists > 0);
  // Make sure the extended decl info is allocated.
  if (!hasExtInfo()) {
    // Save (non-extended) type source info pointer.
    TypeSourceInfo *savedTInfo = DeclInfo.get<TypeSourceInfo*>();
    // Allocate external info struct.
    DeclInfo = new (getASTContext()) ExtInfo;
    // Restore savedTInfo into (extended) decl info.
    getExtInfo()->TInfo = savedTInfo;
  }
  // Set the template parameter lists info.
  getExtInfo()->setTemplateParameterListsInfo(Context, NumTPLists, TPLists);
}

SourceLocation DeclaratorDecl::getOuterLocStart() const {
  return getTemplateOrInnerLocStart(this);
}

namespace {

// Helper function: returns true if QT is or contains a type
// having a postfix component.
bool typeIsPostfix(clang::QualType QT) {
  while (true) {
    const Type* T = QT.getTypePtr();
    switch (T->getTypeClass()) {
    default:
      return false;
    case Type::Pointer:
      QT = cast<PointerType>(T)->getPointeeType();
      break;
    case Type::BlockPointer:
      QT = cast<BlockPointerType>(T)->getPointeeType();
      break;
    case Type::MemberPointer:
      QT = cast<MemberPointerType>(T)->getPointeeType();
      break;
    case Type::LValueReference:
    case Type::RValueReference:
      QT = cast<ReferenceType>(T)->getPointeeType();
      break;
    case Type::PackExpansion:
      QT = cast<PackExpansionType>(T)->getPattern();
      break;
    case Type::Paren:
    case Type::ConstantArray:
    case Type::DependentSizedArray:
    case Type::IncompleteArray:
    case Type::VariableArray:
    case Type::FunctionProto:
    case Type::FunctionNoProto:
      return true;
    }
  }
}

} // namespace

SourceRange DeclaratorDecl::getSourceRange() const {
  SourceLocation RangeEnd = getLocation();
  if (TypeSourceInfo *TInfo = getTypeSourceInfo()) {
    // If the declaration has no name or the type extends past the name take the
    // end location of the type.
    if (!getDeclName() || typeIsPostfix(TInfo->getType()))
      RangeEnd = TInfo->getTypeLoc().getSourceRange().getEnd();
  }
  return SourceRange(getOuterLocStart(), RangeEnd);
}

void
QualifierInfo::setTemplateParameterListsInfo(ASTContext &Context,
                                             unsigned NumTPLists,
                                             TemplateParameterList **TPLists) {
  assert((NumTPLists == 0 || TPLists != nullptr) &&
         "Empty array of template parameters with positive size!");

  // Free previous template parameters (if any).
  if (NumTemplParamLists > 0) {
    Context.Deallocate(TemplParamLists);
    TemplParamLists = nullptr;
    NumTemplParamLists = 0;
  }
  // Set info on matched template parameter lists (if any).
  if (NumTPLists > 0) {
    TemplParamLists = new (Context) TemplateParameterList*[NumTPLists];
    NumTemplParamLists = NumTPLists;
    std::copy(TPLists, TPLists + NumTPLists, TemplParamLists);
  }
}

//===----------------------------------------------------------------------===//
// VarDecl Implementation
//===----------------------------------------------------------------------===//

const char *VarDecl::getStorageClassSpecifierString(StorageClass SC) {
  switch (SC) {
  case SC_None:                 break;
  case SC_Auto:                 return "auto";
  case SC_Extern:               return "extern";
  case SC_OpenCLWorkGroupLocal: return "<<work-group-local>>";
  case SC_PrivateExtern:        return "__private_extern__";
  case SC_Register:             return "register";
  case SC_Static:               return "static";
  }

  llvm_unreachable("Invalid storage class");
}

VarDecl::VarDecl(Kind DK, ASTContext &C, DeclContext *DC,
                 SourceLocation StartLoc, SourceLocation IdLoc,
                 IdentifierInfo *Id, QualType T, TypeSourceInfo *TInfo,
                 StorageClass SC)
    : DeclaratorDecl(DK, DC, IdLoc, Id, T, TInfo, StartLoc),
      redeclarable_base(C), Init() {
  static_assert(sizeof(VarDeclBitfields) <= sizeof(unsigned),
                "VarDeclBitfields too large!");
  static_assert(sizeof(ParmVarDeclBitfields) <= sizeof(unsigned),
                "ParmVarDeclBitfields too large!");
  static_assert(sizeof(NonParmVarDeclBitfields) <= sizeof(unsigned),
                "NonParmVarDeclBitfields too large!");
  AllBits = 0;
  VarDeclBits.SClass = SC;
  // Everything else is implicitly initialized to false.
}

VarDecl *VarDecl::Create(ASTContext &C, DeclContext *DC,
                         SourceLocation StartL, SourceLocation IdL,
                         IdentifierInfo *Id, QualType T, TypeSourceInfo *TInfo,
                         StorageClass S) {
  return new (C, DC) VarDecl(Var, C, DC, StartL, IdL, Id, T, TInfo, S);
}

VarDecl *VarDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  return new (C, ID)
      VarDecl(Var, C, nullptr, SourceLocation(), SourceLocation(), nullptr,
              QualType(), nullptr, SC_None);
}

void VarDecl::setStorageClass(StorageClass SC) {
  assert(isLegalForVariable(SC));
  VarDeclBits.SClass = SC;
}

VarDecl::TLSKind VarDecl::getTLSKind() const {
  switch (VarDeclBits.TSCSpec) {
  case TSCS_unspecified:
    if (!hasAttr<ThreadAttr>())
      return TLS_None;
    return getASTContext().getLangOpts().isCompatibleWithMSVC(
               LangOptions::MSVC2015)
               ? TLS_Dynamic
               : TLS_Static;
  case TSCS___thread: // Fall through.
  case TSCS__Thread_local:
      return TLS_Static;
  case TSCS_thread_local:
    return TLS_Dynamic;
  }
  llvm_unreachable("Unknown thread storage class specifier!");
}

SourceRange VarDecl::getSourceRange() const {
  if (const Expr *Init = getInit()) {
    SourceLocation InitEnd = Init->getLocEnd();
    // If Init is implicit, ignore its source range and fallback on 
    // DeclaratorDecl::getSourceRange() to handle postfix elements.
    if (InitEnd.isValid() && InitEnd != getLocation())
      return SourceRange(getOuterLocStart(), InitEnd);
  }
  return DeclaratorDecl::getSourceRange();
}

template<typename T>
static LanguageLinkage getDeclLanguageLinkage(const T &D) {
  // C++ [dcl.link]p1: All function types, function names with external linkage,
  // and variable names with external linkage have a language linkage.
  if (!D.hasExternalFormalLinkage())
    return NoLanguageLinkage;

  // Language linkage is a C++ concept, but saying that everything else in C has
  // C language linkage fits the implementation nicely.
  ASTContext &Context = D.getASTContext();
  if (!Context.getLangOpts().CPlusPlus)
    return CLanguageLinkage;

  // C++ [dcl.link]p4: A C language linkage is ignored in determining the
  // language linkage of the names of class members and the function type of
  // class member functions.
  const DeclContext *DC = D.getDeclContext();
  if (DC->isRecord())
    return CXXLanguageLinkage;

  // If the first decl is in an extern "C" context, any other redeclaration
  // will have C language linkage. If the first one is not in an extern "C"
  // context, we would have reported an error for any other decl being in one.
  if (isFirstInExternCContext(&D))
    return CLanguageLinkage;
  return CXXLanguageLinkage;
}

template<typename T>
static bool isDeclExternC(const T &D) {
  // Since the context is ignored for class members, they can only have C++
  // language linkage or no language linkage.
  const DeclContext *DC = D.getDeclContext();
  if (DC->isRecord()) {
    assert(D.getASTContext().getLangOpts().CPlusPlus);
    return false;
  }

  return D.getLanguageLinkage() == CLanguageLinkage;
}

LanguageLinkage VarDecl::getLanguageLinkage() const {
  return getDeclLanguageLinkage(*this);
}

bool VarDecl::isExternC() const {
  return isDeclExternC(*this);
}

bool VarDecl::isInExternCContext() const {
  return getLexicalDeclContext()->isExternCContext();
}

bool VarDecl::isInExternCXXContext() const {
  return getLexicalDeclContext()->isExternCXXContext();
}

VarDecl *VarDecl::getCanonicalDecl() { return getFirstDecl(); }

VarDecl::DefinitionKind
VarDecl::isThisDeclarationADefinition(ASTContext &C) const {
  // C++ [basic.def]p2:
  //   A declaration is a definition unless [...] it contains the 'extern'
  //   specifier or a linkage-specification and neither an initializer [...],
  //   it declares a static data member in a class declaration [...].
  // C++1y [temp.expl.spec]p15:
  //   An explicit specialization of a static data member or an explicit
  //   specialization of a static data member template is a definition if the
  //   declaration includes an initializer; otherwise, it is a declaration.
  //
  // FIXME: How do you declare (but not define) a partial specialization of
  // a static data member template outside the containing class?
  if (isStaticDataMember()) {
    if (isOutOfLine() &&
        (hasInit() ||
         // If the first declaration is out-of-line, this may be an
         // instantiation of an out-of-line partial specialization of a variable
         // template for which we have not yet instantiated the initializer.
         (getFirstDecl()->isOutOfLine()
              ? getTemplateSpecializationKind() == TSK_Undeclared
              : getTemplateSpecializationKind() !=
                    TSK_ExplicitSpecialization) ||
         isa<VarTemplatePartialSpecializationDecl>(this)))
      return Definition;
    else
      return DeclarationOnly;
  }
  // C99 6.7p5:
  //   A definition of an identifier is a declaration for that identifier that
  //   [...] causes storage to be reserved for that object.
  // Note: that applies for all non-file-scope objects.
  // C99 6.9.2p1:
  //   If the declaration of an identifier for an object has file scope and an
  //   initializer, the declaration is an external definition for the identifier
  if (hasInit())
    return Definition;

  if (hasAttr<AliasAttr>())
    return Definition;

  if (const auto *SAA = getAttr<SelectAnyAttr>())
    if (!SAA->isInherited())
      return Definition;

  // A variable template specialization (other than a static data member
  // template or an explicit specialization) is a declaration until we
  // instantiate its initializer.
  if (isa<VarTemplateSpecializationDecl>(this) &&
      getTemplateSpecializationKind() != TSK_ExplicitSpecialization)
    return DeclarationOnly;

  if (hasExternalStorage())
    return DeclarationOnly;

  // [dcl.link] p7:
  //   A declaration directly contained in a linkage-specification is treated
  //   as if it contains the extern specifier for the purpose of determining
  //   the linkage of the declared name and whether it is a definition.
  if (isSingleLineLanguageLinkage(*this))
    return DeclarationOnly;

  // C99 6.9.2p2:
  //   A declaration of an object that has file scope without an initializer,
  //   and without a storage class specifier or the scs 'static', constitutes
  //   a tentative definition.
  // No such thing in C++.
  if (!C.getLangOpts().CPlusPlus && isFileVarDecl())
    return TentativeDefinition;

  // What's left is (in C, block-scope) declarations without initializers or
  // external storage. These are definitions.
  return Definition;
}

VarDecl *VarDecl::getActingDefinition() {
  DefinitionKind Kind = isThisDeclarationADefinition();
  if (Kind != TentativeDefinition)
    return nullptr;

  VarDecl *LastTentative = nullptr;
  VarDecl *First = getFirstDecl();
  for (auto I : First->redecls()) {
    Kind = I->isThisDeclarationADefinition();
    if (Kind == Definition)
      return nullptr;
    else if (Kind == TentativeDefinition)
      LastTentative = I;
  }
  return LastTentative;
}

VarDecl *VarDecl::getDefinition(ASTContext &C) {
  VarDecl *First = getFirstDecl();
  for (auto I : First->redecls()) {
    if (I->isThisDeclarationADefinition(C) == Definition)
      return I;
  }
  return nullptr;
}

VarDecl::DefinitionKind VarDecl::hasDefinition(ASTContext &C) const {
  DefinitionKind Kind = DeclarationOnly;
  
  const VarDecl *First = getFirstDecl();
  for (auto I : First->redecls()) {
    Kind = std::max(Kind, I->isThisDeclarationADefinition(C));
    if (Kind == Definition)
      break;
  }

  return Kind;
}

const Expr *VarDecl::getAnyInitializer(const VarDecl *&D) const {
  for (auto I : redecls()) {
    if (auto Expr = I->getInit()) {
      D = I;
      return Expr;
    }
  }
  return nullptr;
}

bool VarDecl::isOutOfLine() const {
  if (Decl::isOutOfLine())
    return true;

  if (!isStaticDataMember())
    return false;

  // If this static data member was instantiated from a static data member of
  // a class template, check whether that static data member was defined 
  // out-of-line.
  if (VarDecl *VD = getInstantiatedFromStaticDataMember())
    return VD->isOutOfLine();
  
  return false;
}

VarDecl *VarDecl::getOutOfLineDefinition() {
  if (!isStaticDataMember())
    return nullptr;

  for (auto RD : redecls()) {
    if (RD->getLexicalDeclContext()->isFileContext())
      return RD;
  }

  return nullptr;
}

void VarDecl::setInit(Expr *I) {
  if (EvaluatedStmt *Eval = Init.dyn_cast<EvaluatedStmt *>()) {
    Eval->~EvaluatedStmt();
    getASTContext().Deallocate(Eval);
  }

  Init = I;
}

bool VarDecl::isUsableInConstantExpressions(ASTContext &C) const {
  const LangOptions &Lang = C.getLangOpts();

  if (!Lang.CPlusPlus)
    return false;

  // In C++11, any variable of reference type can be used in a constant
  // expression if it is initialized by a constant expression.
  if (Lang.CPlusPlus11 && getType()->isReferenceType())
    return true;

  // Only const objects can be used in constant expressions in C++. C++98 does
  // not require the variable to be non-volatile, but we consider this to be a
  // defect.
  if (!getType().isConstQualified() || getType().isVolatileQualified())
    return false;

  // In C++, const, non-volatile variables of integral or enumeration types
  // can be used in constant expressions.
  if (getType()->isIntegralOrEnumerationType())
    return true;

  // Additionally, in C++11, non-volatile constexpr variables can be used in
  // constant expressions.
  return Lang.CPlusPlus11 && isConstexpr();
}

/// Convert the initializer for this declaration to the elaborated EvaluatedStmt
/// form, which contains extra information on the evaluated value of the
/// initializer.
EvaluatedStmt *VarDecl::ensureEvaluatedStmt() const {
  EvaluatedStmt *Eval = Init.dyn_cast<EvaluatedStmt *>();
  if (!Eval) {
    Stmt *S = Init.get<Stmt *>();
    // Note: EvaluatedStmt contains an APValue, which usually holds
    // resources not allocated from the ASTContext.  We need to do some
    // work to avoid leaking those, but we do so in VarDecl::evaluateValue
    // where we can detect whether there's anything to clean up or not.
    Eval = new (getASTContext()) EvaluatedStmt;
    Eval->Value = S;
    Init = Eval;
  }
  return Eval;
}

APValue *VarDecl::evaluateValue() const {
  SmallVector<PartialDiagnosticAt, 8> Notes;
  return evaluateValue(Notes);
}

namespace {
// Destroy an APValue that was allocated in an ASTContext.
void DestroyAPValue(void* UntypedValue) {
  static_cast<APValue*>(UntypedValue)->~APValue();
}
} // namespace

APValue *VarDecl::evaluateValue(
    SmallVectorImpl<PartialDiagnosticAt> &Notes) const {
  EvaluatedStmt *Eval = ensureEvaluatedStmt();

  // We only produce notes indicating why an initializer is non-constant the
  // first time it is evaluated. FIXME: The notes won't always be emitted the
  // first time we try evaluation, so might not be produced at all.
  if (Eval->WasEvaluated)
    return Eval->Evaluated.isUninit() ? nullptr : &Eval->Evaluated;

  const Expr *Init = cast<Expr>(Eval->Value);
  assert(!Init->isValueDependent());

  if (Eval->IsEvaluating) {
    // FIXME: Produce a diagnostic for self-initialization.
    Eval->CheckedICE = true;
    Eval->IsICE = false;
    return nullptr;
  }

  Eval->IsEvaluating = true;

  bool Result = Init->EvaluateAsInitializer(Eval->Evaluated, getASTContext(),
                                            this, Notes);

  // Ensure the computed APValue is cleaned up later if evaluation succeeded,
  // or that it's empty (so that there's nothing to clean up) if evaluation
  // failed.
  if (!Result)
    Eval->Evaluated = APValue();
  else if (Eval->Evaluated.needsCleanup())
    getASTContext().AddDeallocation(DestroyAPValue, &Eval->Evaluated);

  Eval->IsEvaluating = false;
  Eval->WasEvaluated = true;

  // In C++11, we have determined whether the initializer was a constant
  // expression as a side-effect.
  if (getASTContext().getLangOpts().CPlusPlus11 && !Eval->CheckedICE) {
    Eval->CheckedICE = true;
    Eval->IsICE = Result && Notes.empty();
  }

  return Result ? &Eval->Evaluated : nullptr;
}

bool VarDecl::checkInitIsICE() const {
  // Initializers of weak variables are never ICEs.
  if (isWeak())
    return false;

  EvaluatedStmt *Eval = ensureEvaluatedStmt();
  if (Eval->CheckedICE)
    // We have already checked whether this subexpression is an
    // integral constant expression.
    return Eval->IsICE;

  const Expr *Init = cast<Expr>(Eval->Value);
  assert(!Init->isValueDependent());

  // In C++11, evaluate the initializer to check whether it's a constant
  // expression.
  if (getASTContext().getLangOpts().CPlusPlus11) {
    SmallVector<PartialDiagnosticAt, 8> Notes;
    evaluateValue(Notes);
    return Eval->IsICE;
  }

  // It's an ICE whether or not the definition we found is
  // out-of-line.  See DR 721 and the discussion in Clang PR
  // 6206 for details.

  if (Eval->CheckingICE)
    return false;
  Eval->CheckingICE = true;

  Eval->IsICE = Init->isIntegerConstantExpr(getASTContext());
  Eval->CheckingICE = false;
  Eval->CheckedICE = true;
  return Eval->IsICE;
}

VarDecl *VarDecl::getInstantiatedFromStaticDataMember() const {
  if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo())
    return cast<VarDecl>(MSI->getInstantiatedFrom());

  return nullptr;
}

TemplateSpecializationKind VarDecl::getTemplateSpecializationKind() const {
  if (const VarTemplateSpecializationDecl *Spec =
          dyn_cast<VarTemplateSpecializationDecl>(this))
    return Spec->getSpecializationKind();

  if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo())
    return MSI->getTemplateSpecializationKind();

  return TSK_Undeclared;
}

SourceLocation VarDecl::getPointOfInstantiation() const {
  if (const VarTemplateSpecializationDecl *Spec =
          dyn_cast<VarTemplateSpecializationDecl>(this))
    return Spec->getPointOfInstantiation();

  if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo())
    return MSI->getPointOfInstantiation();

  return SourceLocation();
}

VarTemplateDecl *VarDecl::getDescribedVarTemplate() const {
  return getASTContext().getTemplateOrSpecializationInfo(this)
      .dyn_cast<VarTemplateDecl *>();
}

void VarDecl::setDescribedVarTemplate(VarTemplateDecl *Template) {
  getASTContext().setTemplateOrSpecializationInfo(this, Template);
}

MemberSpecializationInfo *VarDecl::getMemberSpecializationInfo() const {
  if (isStaticDataMember())
    // FIXME: Remove ?
    // return getASTContext().getInstantiatedFromStaticDataMember(this);
    return getASTContext().getTemplateOrSpecializationInfo(this)
        .dyn_cast<MemberSpecializationInfo *>();
  return nullptr;
}

void VarDecl::setTemplateSpecializationKind(TemplateSpecializationKind TSK,
                                         SourceLocation PointOfInstantiation) {
  assert((isa<VarTemplateSpecializationDecl>(this) ||
          getMemberSpecializationInfo()) &&
         "not a variable or static data member template specialization");

  if (VarTemplateSpecializationDecl *Spec =
          dyn_cast<VarTemplateSpecializationDecl>(this)) {
    Spec->setSpecializationKind(TSK);
    if (TSK != TSK_ExplicitSpecialization && PointOfInstantiation.isValid() &&
        Spec->getPointOfInstantiation().isInvalid())
      Spec->setPointOfInstantiation(PointOfInstantiation);
  }

  if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo()) {
    MSI->setTemplateSpecializationKind(TSK);
    if (TSK != TSK_ExplicitSpecialization && PointOfInstantiation.isValid() &&
        MSI->getPointOfInstantiation().isInvalid())
      MSI->setPointOfInstantiation(PointOfInstantiation);
  }
}

void
VarDecl::setInstantiationOfStaticDataMember(VarDecl *VD,
                                            TemplateSpecializationKind TSK) {
  assert(getASTContext().getTemplateOrSpecializationInfo(this).isNull() &&
         "Previous template or instantiation?");
  getASTContext().setInstantiatedFromStaticDataMember(this, VD, TSK);
}

//===----------------------------------------------------------------------===//
// ParmVarDecl Implementation
//===----------------------------------------------------------------------===//

ParmVarDecl *ParmVarDecl::Create(ASTContext &C, DeclContext *DC,
                                 SourceLocation StartLoc,
                                 SourceLocation IdLoc, IdentifierInfo *Id,
                                 QualType T, TypeSourceInfo *TInfo,
                                 StorageClass S, Expr *DefArg) {
  return new (C, DC) ParmVarDecl(ParmVar, C, DC, StartLoc, IdLoc, Id, T, TInfo,
                                 S, DefArg);
}

QualType ParmVarDecl::getOriginalType() const {
  TypeSourceInfo *TSI = getTypeSourceInfo();
  QualType T = TSI ? TSI->getType() : getType();
  if (const DecayedType *DT = dyn_cast<DecayedType>(T))
    return DT->getOriginalType();
  return T;
}

ParmVarDecl *ParmVarDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  return new (C, ID)
      ParmVarDecl(ParmVar, C, nullptr, SourceLocation(), SourceLocation(),
                  nullptr, QualType(), nullptr, SC_None, nullptr);
}

SourceRange ParmVarDecl::getSourceRange() const {
  if (!hasInheritedDefaultArg()) {
    SourceRange ArgRange = getDefaultArgRange();
    if (ArgRange.isValid())
      return SourceRange(getOuterLocStart(), ArgRange.getEnd());
  }

  // DeclaratorDecl considers the range of postfix types as overlapping with the
  // declaration name, but this is not the case with parameters in ObjC methods.
  if (isa<ObjCMethodDecl>(getDeclContext()))
    return SourceRange(DeclaratorDecl::getLocStart(), getLocation());

  return DeclaratorDecl::getSourceRange();
}

Expr *ParmVarDecl::getDefaultArg() {
  assert(!hasUnparsedDefaultArg() && "Default argument is not yet parsed!");
  assert(!hasUninstantiatedDefaultArg() &&
         "Default argument is not yet instantiated!");
  
  Expr *Arg = getInit();
  if (ExprWithCleanups *E = dyn_cast_or_null<ExprWithCleanups>(Arg))
    return E->getSubExpr();

  return Arg;
}

SourceRange ParmVarDecl::getDefaultArgRange() const {
  if (const Expr *E = getInit())
    return E->getSourceRange();

  if (hasUninstantiatedDefaultArg())
    return getUninstantiatedDefaultArg()->getSourceRange();

  return SourceRange();
}

bool ParmVarDecl::isParameterPack() const {
  return isa<PackExpansionType>(getType());
}

void ParmVarDecl::setParameterIndexLarge(unsigned parameterIndex) {
  getASTContext().setParameterIndex(this, parameterIndex);
  ParmVarDeclBits.ParameterIndex = ParameterIndexSentinel;
}

unsigned ParmVarDecl::getParameterIndexLarge() const {
  return getASTContext().getParameterIndex(this);
}

//===----------------------------------------------------------------------===//
// FunctionDecl Implementation
//===----------------------------------------------------------------------===//

void FunctionDecl::getNameForDiagnostic(
    raw_ostream &OS, const PrintingPolicy &Policy, bool Qualified) const {
  NamedDecl::getNameForDiagnostic(OS, Policy, Qualified);
  const TemplateArgumentList *TemplateArgs = getTemplateSpecializationArgs();
  if (TemplateArgs)
    TemplateSpecializationType::PrintTemplateArgumentList(
        OS, TemplateArgs->data(), TemplateArgs->size(), Policy);
}

bool FunctionDecl::isVariadic() const {
  if (const FunctionProtoType *FT = getType()->getAs<FunctionProtoType>())
    return FT->isVariadic();
  return false;
}

bool FunctionDecl::hasBody(const FunctionDecl *&Definition) const {
  for (auto I : redecls()) {
    if (I->Body || I->IsLateTemplateParsed) {
      Definition = I;
      return true;
    }
  }

  return false;
}

bool FunctionDecl::hasTrivialBody() const
{
  Stmt *S = getBody();
  if (!S) {
    // Since we don't have a body for this function, we don't know if it's
    // trivial or not.
    return false;
  }

  if (isa<CompoundStmt>(S) && cast<CompoundStmt>(S)->body_empty())
    return true;
  return false;
}

bool FunctionDecl::isDefined(const FunctionDecl *&Definition) const {
  for (auto I : redecls()) {
    if (I->IsDeleted || I->IsDefaulted || I->Body || I->IsLateTemplateParsed ||
        I->hasAttr<AliasAttr>()) {
      Definition = I->IsDeleted ? I->getCanonicalDecl() : I;
      return true;
    }
  }

  return false;
}

Stmt *FunctionDecl::getBody(const FunctionDecl *&Definition) const {
  if (!hasBody(Definition))
    return nullptr;

  if (Definition->Body)
    return Definition->Body.get(getASTContext().getExternalSource());

  return nullptr;
}

void FunctionDecl::setBody(Stmt *B) {
  Body = B;
  if (B)
    EndRangeLoc = B->getLocEnd();
}

void FunctionDecl::setPure(bool P) {
  IsPure = P;
  if (P)
    if (CXXRecordDecl *Parent = dyn_cast<CXXRecordDecl>(getDeclContext()))
      Parent->markedVirtualFunctionPure();
}

template<std::size_t Len>
static bool isNamed(const NamedDecl *ND, const char (&Str)[Len]) {
  IdentifierInfo *II = ND->getIdentifier();
  return II && II->isStr(Str);
}

bool FunctionDecl::isMain() const {
  const TranslationUnitDecl *tunit =
    dyn_cast<TranslationUnitDecl>(getDeclContext()->getRedeclContext());
  return tunit &&
         !tunit->getASTContext().getLangOpts().Freestanding &&
         isNamed(this, "main");
}

bool FunctionDecl::isMSVCRTEntryPoint() const {
  const TranslationUnitDecl *TUnit =
      dyn_cast<TranslationUnitDecl>(getDeclContext()->getRedeclContext());
  if (!TUnit)
    return false;

  // Even though we aren't really targeting MSVCRT if we are freestanding,
  // semantic analysis for these functions remains the same.

  // MSVCRT entry points only exist on MSVCRT targets.
  if (!TUnit->getASTContext().getTargetInfo().getTriple().isOSMSVCRT())
    return false;

  // Nameless functions like constructors cannot be entry points.
  if (!getIdentifier())
    return false;

  return llvm::StringSwitch<bool>(getName())
      .Cases("main",     // an ANSI console app
             "wmain",    // a Unicode console App
             "WinMain",  // an ANSI GUI app
             "wWinMain", // a Unicode GUI app
             "DllMain",  // a DLL
             true)
      .Default(false);
}

bool FunctionDecl::isReservedGlobalPlacementOperator() const {
  assert(getDeclName().getNameKind() == DeclarationName::CXXOperatorName);
  assert(getDeclName().getCXXOverloadedOperator() == OO_New ||
         getDeclName().getCXXOverloadedOperator() == OO_Delete ||
         getDeclName().getCXXOverloadedOperator() == OO_Array_New ||
         getDeclName().getCXXOverloadedOperator() == OO_Array_Delete);

  if (!getDeclContext()->getRedeclContext()->isTranslationUnit())
    return false;

  const FunctionProtoType *proto = getType()->castAs<FunctionProtoType>();
  if (proto->getNumParams() != 2 || proto->isVariadic())
    return false;

  ASTContext &Context =
    cast<TranslationUnitDecl>(getDeclContext()->getRedeclContext())
      ->getASTContext();

  // The result type and first argument type are constant across all
  // these operators.  The second argument must be exactly void*.
  return (proto->getParamType(1).getCanonicalType() == Context.VoidPtrTy);
}

bool FunctionDecl::isReplaceableGlobalAllocationFunction() const {
  if (getDeclName().getNameKind() != DeclarationName::CXXOperatorName)
    return false;
  if (getDeclName().getCXXOverloadedOperator() != OO_New &&
      getDeclName().getCXXOverloadedOperator() != OO_Delete &&
      getDeclName().getCXXOverloadedOperator() != OO_Array_New &&
      getDeclName().getCXXOverloadedOperator() != OO_Array_Delete)
    return false;

  if (isa<CXXRecordDecl>(getDeclContext()))
    return false;

  // This can only fail for an invalid 'operator new' declaration.
  if (!getDeclContext()->getRedeclContext()->isTranslationUnit())
    return false;

  const FunctionProtoType *FPT = getType()->castAs<FunctionProtoType>();
  if (FPT->getNumParams() == 0 || FPT->getNumParams() > 2 || FPT->isVariadic())
    return false;

  // If this is a single-parameter function, it must be a replaceable global
  // allocation or deallocation function.
  if (FPT->getNumParams() == 1)
    return true;

  // Otherwise, we're looking for a second parameter whose type is
  // 'const std::nothrow_t &', or, in C++1y, 'std::size_t'.
  QualType Ty = FPT->getParamType(1);
  ASTContext &Ctx = getASTContext();
  if (Ctx.getLangOpts().SizedDeallocation &&
      Ctx.hasSameType(Ty, Ctx.getSizeType()))
    return true;
  if (!Ty->isReferenceType())
    return false;
  Ty = Ty->getPointeeType();
  if (Ty.getCVRQualifiers() != Qualifiers::Const)
    return false;
  const CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
  return RD && isNamed(RD, "nothrow_t") && RD->isInStdNamespace();
}

LanguageLinkage FunctionDecl::getLanguageLinkage() const {
  return getDeclLanguageLinkage(*this);
}

bool FunctionDecl::isExternC() const {
  return isDeclExternC(*this);
}

bool FunctionDecl::isInExternCContext() const {
  return getLexicalDeclContext()->isExternCContext();
}

bool FunctionDecl::isInExternCXXContext() const {
  return getLexicalDeclContext()->isExternCXXContext();
}

bool FunctionDecl::isGlobal() const {
  if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(this))
    return Method->isStatic();

  if (getCanonicalDecl()->getStorageClass() == SC_Static)
    return false;

  for (const DeclContext *DC = getDeclContext();
       DC->isNamespace();
       DC = DC->getParent()) {
    if (const NamespaceDecl *Namespace = cast<NamespaceDecl>(DC)) {
      if (!Namespace->getDeclName())
        return false;
      break;
    }
  }

  return true;
}

bool FunctionDecl::isNoReturn() const {
  return hasAttr<NoReturnAttr>() || hasAttr<CXX11NoReturnAttr>() ||
         hasAttr<C11NoReturnAttr>() ||
         getType()->getAs<FunctionType>()->getNoReturnAttr();
}

void
FunctionDecl::setPreviousDeclaration(FunctionDecl *PrevDecl) {
  redeclarable_base::setPreviousDecl(PrevDecl);

  if (FunctionTemplateDecl *FunTmpl = getDescribedFunctionTemplate()) {
    FunctionTemplateDecl *PrevFunTmpl
      = PrevDecl? PrevDecl->getDescribedFunctionTemplate() : nullptr;
    assert((!PrevDecl || PrevFunTmpl) && "Function/function template mismatch");
    FunTmpl->setPreviousDecl(PrevFunTmpl);
  }
  
  if (PrevDecl && PrevDecl->IsInline)
    IsInline = true;
}

FunctionDecl *FunctionDecl::getCanonicalDecl() { return getFirstDecl(); }

/// \brief Returns a value indicating whether this function
/// corresponds to a builtin function.
///
/// The function corresponds to a built-in function if it is
/// declared at translation scope or within an extern "C" block and
/// its name matches with the name of a builtin. The returned value
/// will be 0 for functions that do not correspond to a builtin, a
/// value of type \c Builtin::ID if in the target-independent range
/// \c [1,Builtin::First), or a target-specific builtin value.
unsigned FunctionDecl::getBuiltinID() const {
  if (!getIdentifier())
    return 0;

  unsigned BuiltinID = getIdentifier()->getBuiltinID();
  if (!BuiltinID)
    return 0;

  ASTContext &Context = getASTContext();
  if (Context.getLangOpts().CPlusPlus) {
    const LinkageSpecDecl *LinkageDecl = dyn_cast<LinkageSpecDecl>(
        getFirstDecl()->getDeclContext());
    // In C++, the first declaration of a builtin is always inside an implicit
    // extern "C".
    // FIXME: A recognised library function may not be directly in an extern "C"
    // declaration, for instance "extern "C" { namespace std { decl } }".
    if (!LinkageDecl) {
      if (BuiltinID == Builtin::BI__GetExceptionInfo &&
          Context.getTargetInfo().getCXXABI().isMicrosoft() &&
          isInStdNamespace())
        return Builtin::BI__GetExceptionInfo;
      return 0;
    }
    if (LinkageDecl->getLanguage() != LinkageSpecDecl::lang_c)
      return 0;
  }

  // If the function is marked "overloadable", it has a different mangled name
  // and is not the C library function.
  if (hasAttr<OverloadableAttr>())
    return 0;

  if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
    return BuiltinID;

  // This function has the name of a known C library
  // function. Determine whether it actually refers to the C library
  // function or whether it just has the same name.

  // If this is a static function, it's not a builtin.
  if (getStorageClass() == SC_Static)
    return 0;

  return BuiltinID;
}


/// getNumParams - Return the number of parameters this function must have
/// based on its FunctionType.  This is the length of the ParamInfo array
/// after it has been created.
unsigned FunctionDecl::getNumParams() const {
  const FunctionProtoType *FPT = getType()->getAs<FunctionProtoType>();
  return FPT ? FPT->getNumParams() : 0;
}

void FunctionDecl::setParams(ASTContext &C,
                             ArrayRef<ParmVarDecl *> NewParamInfo) {
  assert(!ParamInfo && "Already has param info!");
  assert(NewParamInfo.size() == getNumParams() && "Parameter count mismatch!");

  // Zero params -> null pointer.
  if (!NewParamInfo.empty()) {
    ParamInfo = new (C) ParmVarDecl*[NewParamInfo.size()];
    std::copy(NewParamInfo.begin(), NewParamInfo.end(), ParamInfo);
  }
}

void FunctionDecl::setDeclsInPrototypeScope(ArrayRef<NamedDecl *> NewDecls) {
  assert(DeclsInPrototypeScope.empty() && "Already has prototype decls!");

  if (!NewDecls.empty()) {
    NamedDecl **A = new (getASTContext()) NamedDecl*[NewDecls.size()];
    std::copy(NewDecls.begin(), NewDecls.end(), A);
    DeclsInPrototypeScope = llvm::makeArrayRef(A, NewDecls.size());
    // Move declarations introduced in prototype to the function context.
    for (auto I : NewDecls) {
      DeclContext *DC = I->getDeclContext();
      // Forward-declared reference to an enumeration is not added to
      // declaration scope, so skip declaration that is absent from its
      // declaration contexts.
      if (DC->containsDecl(I)) {
          DC->removeDecl(I);
          I->setDeclContext(this);
          addDecl(I);
      }
    }
  }
}

/// getMinRequiredArguments - Returns the minimum number of arguments
/// needed to call this function. This may be fewer than the number of
/// function parameters, if some of the parameters have default
/// arguments (in C++) or are parameter packs (C++11).
unsigned FunctionDecl::getMinRequiredArguments() const {
  if (!getASTContext().getLangOpts().CPlusPlus)
    return getNumParams();

  unsigned NumRequiredArgs = 0;
  for (auto *Param : params())
    if (!Param->isParameterPack() && !Param->hasDefaultArg())
      ++NumRequiredArgs;
  return NumRequiredArgs;
}

/// \brief The combination of the extern and inline keywords under MSVC forces
/// the function to be required.
///
/// Note: This function assumes that we will only get called when isInlined()
/// would return true for this FunctionDecl.
bool FunctionDecl::isMSExternInline() const {
  assert(isInlined() && "expected to get called on an inlined function!");

  const ASTContext &Context = getASTContext();
  if (!Context.getLangOpts().MSVCCompat && !hasAttr<DLLExportAttr>())
    return false;

  for (const FunctionDecl *FD = getMostRecentDecl(); FD;
       FD = FD->getPreviousDecl())
    if (FD->getStorageClass() == SC_Extern)
      return true;

  return false;
}

static bool redeclForcesDefMSVC(const FunctionDecl *Redecl) {
  if (Redecl->getStorageClass() != SC_Extern)
    return false;

  for (const FunctionDecl *FD = Redecl->getPreviousDecl(); FD;
       FD = FD->getPreviousDecl())
    if (FD->getStorageClass() == SC_Extern)
      return false;

  return true;
}

static bool RedeclForcesDefC99(const FunctionDecl *Redecl) {
  // Only consider file-scope declarations in this test.
  if (!Redecl->getLexicalDeclContext()->isTranslationUnit())
    return false;

  // Only consider explicit declarations; the presence of a builtin for a
  // libcall shouldn't affect whether a definition is externally visible.
  if (Redecl->isImplicit())
    return false;

  if (!Redecl->isInlineSpecified() || Redecl->getStorageClass() == SC_Extern) 
    return true; // Not an inline definition

  return false;
}

/// \brief For a function declaration in C or C++, determine whether this
/// declaration causes the definition to be externally visible.
///
/// For instance, this determines if adding the current declaration to the set
/// of redeclarations of the given functions causes
/// isInlineDefinitionExternallyVisible to change from false to true.
bool FunctionDecl::doesDeclarationForceExternallyVisibleDefinition() const {
  assert(!doesThisDeclarationHaveABody() &&
         "Must have a declaration without a body.");

  ASTContext &Context = getASTContext();

  if (Context.getLangOpts().MSVCCompat) {
    const FunctionDecl *Definition;
    if (hasBody(Definition) && Definition->isInlined() &&
        redeclForcesDefMSVC(this))
      return true;
  }

  if (Context.getLangOpts().GNUInline || hasAttr<GNUInlineAttr>()) {
    // With GNU inlining, a declaration with 'inline' but not 'extern', forces
    // an externally visible definition.
    //
    // FIXME: What happens if gnu_inline gets added on after the first
    // declaration?
    if (!isInlineSpecified() || getStorageClass() == SC_Extern)
      return false;

    const FunctionDecl *Prev = this;
    bool FoundBody = false;
    while ((Prev = Prev->getPreviousDecl())) {
      FoundBody |= Prev->Body.isValid();

      if (Prev->Body) {
        // If it's not the case that both 'inline' and 'extern' are
        // specified on the definition, then it is always externally visible.
        if (!Prev->isInlineSpecified() ||
            Prev->getStorageClass() != SC_Extern)
          return false;
      } else if (Prev->isInlineSpecified() && 
                 Prev->getStorageClass() != SC_Extern) {
        return false;
      }
    }
    return FoundBody;
  }

  if (Context.getLangOpts().CPlusPlus)
    return false;

  // C99 6.7.4p6:
  //   [...] If all of the file scope declarations for a function in a 
  //   translation unit include the inline function specifier without extern, 
  //   then the definition in that translation unit is an inline definition.
  if (isInlineSpecified() && getStorageClass() != SC_Extern)
    return false;
  const FunctionDecl *Prev = this;
  bool FoundBody = false;
  while ((Prev = Prev->getPreviousDecl())) {
    FoundBody |= Prev->Body.isValid();
    if (RedeclForcesDefC99(Prev))
      return false;
  }
  return FoundBody;
}

SourceRange FunctionDecl::getReturnTypeSourceRange() const {
  const TypeSourceInfo *TSI = getTypeSourceInfo();
  if (!TSI)
    return SourceRange();
  FunctionTypeLoc FTL =
      TSI->getTypeLoc().IgnoreParens().getAs<FunctionTypeLoc>();
  if (!FTL)
    return SourceRange();

  // Skip self-referential return types.
  const SourceManager &SM = getASTContext().getSourceManager();
  SourceRange RTRange = FTL.getReturnLoc().getSourceRange();
  SourceLocation Boundary = getNameInfo().getLocStart();
  if (RTRange.isInvalid() || Boundary.isInvalid() ||
      !SM.isBeforeInTranslationUnit(RTRange.getEnd(), Boundary))
    return SourceRange();

  return RTRange;
}

bool FunctionDecl::hasUnusedResultAttr() const {
  QualType RetType = getReturnType();
  if (RetType->isRecordType()) {
    const CXXRecordDecl *Ret = RetType->getAsCXXRecordDecl();
    const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(this);
    if (Ret && Ret->hasAttr<WarnUnusedResultAttr>() &&
        !(MD && MD->getCorrespondingMethodInClass(Ret, true)))
      return true;
  }
  return hasAttr<WarnUnusedResultAttr>();
}

/// \brief For an inline function definition in C, or for a gnu_inline function
/// in C++, determine whether the definition will be externally visible.
///
/// Inline function definitions are always available for inlining optimizations.
/// However, depending on the language dialect, declaration specifiers, and
/// attributes, the definition of an inline function may or may not be
/// "externally" visible to other translation units in the program.
///
/// In C99, inline definitions are not externally visible by default. However,
/// if even one of the global-scope declarations is marked "extern inline", the
/// inline definition becomes externally visible (C99 6.7.4p6).
///
/// In GNU89 mode, or if the gnu_inline attribute is attached to the function
/// definition, we use the GNU semantics for inline, which are nearly the 
/// opposite of C99 semantics. In particular, "inline" by itself will create 
/// an externally visible symbol, but "extern inline" will not create an 
/// externally visible symbol.
bool FunctionDecl::isInlineDefinitionExternallyVisible() const {
  assert(doesThisDeclarationHaveABody() && "Must have the function definition");
  assert(isInlined() && "Function must be inline");
  ASTContext &Context = getASTContext();
  
  if (Context.getLangOpts().GNUInline || hasAttr<GNUInlineAttr>()) {
    // Note: If you change the logic here, please change
    // doesDeclarationForceExternallyVisibleDefinition as well.
    //
    // If it's not the case that both 'inline' and 'extern' are
    // specified on the definition, then this inline definition is
    // externally visible.
    if (!(isInlineSpecified() && getStorageClass() == SC_Extern))
      return true;
    
    // If any declaration is 'inline' but not 'extern', then this definition
    // is externally visible.
    for (auto Redecl : redecls()) {
      if (Redecl->isInlineSpecified() && 
          Redecl->getStorageClass() != SC_Extern)
        return true;
    }    
    
    return false;
  }

  // The rest of this function is C-only.
  assert(!Context.getLangOpts().CPlusPlus &&
         "should not use C inline rules in C++");

  // C99 6.7.4p6:
  //   [...] If all of the file scope declarations for a function in a 
  //   translation unit include the inline function specifier without extern, 
  //   then the definition in that translation unit is an inline definition.
  for (auto Redecl : redecls()) {
    if (RedeclForcesDefC99(Redecl))
      return true;
  }
  
  // C99 6.7.4p6:
  //   An inline definition does not provide an external definition for the 
  //   function, and does not forbid an external definition in another 
  //   translation unit.
  return false;
}

/// getOverloadedOperator - Which C++ overloaded operator this
/// function represents, if any.
OverloadedOperatorKind FunctionDecl::getOverloadedOperator() const {
  if (getDeclName().getNameKind() == DeclarationName::CXXOperatorName)
    return getDeclName().getCXXOverloadedOperator();
  else
    return OO_None;
}

/// getLiteralIdentifier - The literal suffix identifier this function
/// represents, if any.
const IdentifierInfo *FunctionDecl::getLiteralIdentifier() const {
  if (getDeclName().getNameKind() == DeclarationName::CXXLiteralOperatorName)
    return getDeclName().getCXXLiteralIdentifier();
  else
    return nullptr;
}

FunctionDecl::TemplatedKind FunctionDecl::getTemplatedKind() const {
  if (TemplateOrSpecialization.isNull())
    return TK_NonTemplate;
  if (TemplateOrSpecialization.is<FunctionTemplateDecl *>())
    return TK_FunctionTemplate;
  if (TemplateOrSpecialization.is<MemberSpecializationInfo *>())
    return TK_MemberSpecialization;
  if (TemplateOrSpecialization.is<FunctionTemplateSpecializationInfo *>())
    return TK_FunctionTemplateSpecialization;
  if (TemplateOrSpecialization.is
                               <DependentFunctionTemplateSpecializationInfo*>())
    return TK_DependentFunctionTemplateSpecialization;

  llvm_unreachable("Did we miss a TemplateOrSpecialization type?");
}

FunctionDecl *FunctionDecl::getInstantiatedFromMemberFunction() const {
  if (MemberSpecializationInfo *Info = getMemberSpecializationInfo())
    return cast<FunctionDecl>(Info->getInstantiatedFrom());

  return nullptr;
}

void 
FunctionDecl::setInstantiationOfMemberFunction(ASTContext &C,
                                               FunctionDecl *FD,
                                               TemplateSpecializationKind TSK) {
  assert(TemplateOrSpecialization.isNull() && 
         "Member function is already a specialization");
  MemberSpecializationInfo *Info 
    = new (C) MemberSpecializationInfo(FD, TSK);
  TemplateOrSpecialization = Info;
}

bool FunctionDecl::isImplicitlyInstantiable() const {
  // If the function is invalid, it can't be implicitly instantiated.
  if (isInvalidDecl())
    return false;
  
  switch (getTemplateSpecializationKind()) {
  case TSK_Undeclared:
  case TSK_ExplicitInstantiationDefinition:
    return false;
      
  case TSK_ImplicitInstantiation:
    return true;

  // It is possible to instantiate TSK_ExplicitSpecialization kind
  // if the FunctionDecl has a class scope specialization pattern.
  case TSK_ExplicitSpecialization:
    return getClassScopeSpecializationPattern() != nullptr;

  case TSK_ExplicitInstantiationDeclaration:
    // Handled below.
    break;
  }

  // Find the actual template from which we will instantiate.
  const FunctionDecl *PatternDecl = getTemplateInstantiationPattern();
  bool HasPattern = false;
  if (PatternDecl)
    HasPattern = PatternDecl->hasBody(PatternDecl);
  
  // C++0x [temp.explicit]p9:
  //   Except for inline functions, other explicit instantiation declarations
  //   have the effect of suppressing the implicit instantiation of the entity
  //   to which they refer. 
  if (!HasPattern || !PatternDecl) 
    return true;

  return PatternDecl->isInlined();
}

bool FunctionDecl::isTemplateInstantiation() const {
  switch (getTemplateSpecializationKind()) {
    case TSK_Undeclared:
    case TSK_ExplicitSpecialization:
      return false;      
    case TSK_ImplicitInstantiation:
    case TSK_ExplicitInstantiationDeclaration:
    case TSK_ExplicitInstantiationDefinition:
      return true;
  }
  llvm_unreachable("All TSK values handled.");
}
   
FunctionDecl *FunctionDecl::getTemplateInstantiationPattern() const {
  // Handle class scope explicit specialization special case.
  if (getTemplateSpecializationKind() == TSK_ExplicitSpecialization)
    return getClassScopeSpecializationPattern();
  
  // If this is a generic lambda call operator specialization, its 
  // instantiation pattern is always its primary template's pattern
  // even if its primary template was instantiated from another 
  // member template (which happens with nested generic lambdas).
  // Since a lambda's call operator's body is transformed eagerly, 
  // we don't have to go hunting for a prototype definition template 
  // (i.e. instantiated-from-member-template) to use as an instantiation 
  // pattern.

  if (isGenericLambdaCallOperatorSpecialization(
          dyn_cast<CXXMethodDecl>(this))) {
    assert(getPrimaryTemplate() && "A generic lambda specialization must be "
                                   "generated from a primary call operator "
                                   "template");
    assert(getPrimaryTemplate()->getTemplatedDecl()->getBody() &&
           "A generic lambda call operator template must always have a body - "
           "even if instantiated from a prototype (i.e. as written) member "
           "template");
    return getPrimaryTemplate()->getTemplatedDecl();
  }
  
  if (FunctionTemplateDecl *Primary = getPrimaryTemplate()) {
    while (Primary->getInstantiatedFromMemberTemplate()) {
      // If we have hit a point where the user provided a specialization of
      // this template, we're done looking.
      if (Primary->isMemberSpecialization())
        break;
      Primary = Primary->getInstantiatedFromMemberTemplate();
    }
    
    return Primary->getTemplatedDecl();
  } 
    
  return getInstantiatedFromMemberFunction();
}

FunctionTemplateDecl *FunctionDecl::getPrimaryTemplate() const {
  if (FunctionTemplateSpecializationInfo *Info
        = TemplateOrSpecialization
            .dyn_cast<FunctionTemplateSpecializationInfo*>()) {
    return Info->Template.getPointer();
  }
  return nullptr;
}

FunctionDecl *FunctionDecl::getClassScopeSpecializationPattern() const {
    return getASTContext().getClassScopeSpecializationPattern(this);
}

const TemplateArgumentList *
FunctionDecl::getTemplateSpecializationArgs() const {
  if (FunctionTemplateSpecializationInfo *Info
        = TemplateOrSpecialization
            .dyn_cast<FunctionTemplateSpecializationInfo*>()) {
    return Info->TemplateArguments;
  }
  return nullptr;
}

const ASTTemplateArgumentListInfo *
FunctionDecl::getTemplateSpecializationArgsAsWritten() const {
  if (FunctionTemplateSpecializationInfo *Info
        = TemplateOrSpecialization
            .dyn_cast<FunctionTemplateSpecializationInfo*>()) {
    return Info->TemplateArgumentsAsWritten;
  }
  return nullptr;
}

void
FunctionDecl::setFunctionTemplateSpecialization(ASTContext &C,
                                                FunctionTemplateDecl *Template,
                                     const TemplateArgumentList *TemplateArgs,
                                                void *InsertPos,
                                                TemplateSpecializationKind TSK,
                        const TemplateArgumentListInfo *TemplateArgsAsWritten,
                                          SourceLocation PointOfInstantiation) {
  assert(TSK != TSK_Undeclared && 
         "Must specify the type of function template specialization");
  FunctionTemplateSpecializationInfo *Info
    = TemplateOrSpecialization.dyn_cast<FunctionTemplateSpecializationInfo*>();
  if (!Info)
    Info = FunctionTemplateSpecializationInfo::Create(C, this, Template, TSK,
                                                      TemplateArgs,
                                                      TemplateArgsAsWritten,
                                                      PointOfInstantiation);
  TemplateOrSpecialization = Info;
  Template->addSpecialization(Info, InsertPos);
}

void
FunctionDecl::setDependentTemplateSpecialization(ASTContext &Context,
                                    const UnresolvedSetImpl &Templates,
                             const TemplateArgumentListInfo &TemplateArgs) {
  assert(TemplateOrSpecialization.isNull());
  size_t Size = sizeof(DependentFunctionTemplateSpecializationInfo);
  Size += Templates.size() * sizeof(FunctionTemplateDecl*);
  Size += TemplateArgs.size() * sizeof(TemplateArgumentLoc);
  void *Buffer = Context.Allocate(Size);
  DependentFunctionTemplateSpecializationInfo *Info =
    new (Buffer) DependentFunctionTemplateSpecializationInfo(Templates,
                                                             TemplateArgs);
  TemplateOrSpecialization = Info;
}

DependentFunctionTemplateSpecializationInfo::
DependentFunctionTemplateSpecializationInfo(const UnresolvedSetImpl &Ts,
                                      const TemplateArgumentListInfo &TArgs)
  : AngleLocs(TArgs.getLAngleLoc(), TArgs.getRAngleLoc()) {
  static_assert(sizeof(*this) % llvm::AlignOf<void *>::Alignment == 0,
                "Trailing data is unaligned!");

  d.NumTemplates = Ts.size();
  d.NumArgs = TArgs.size();

  FunctionTemplateDecl **TsArray =
    const_cast<FunctionTemplateDecl**>(getTemplates());
  for (unsigned I = 0, E = Ts.size(); I != E; ++I)
    TsArray[I] = cast<FunctionTemplateDecl>(Ts[I]->getUnderlyingDecl());

  TemplateArgumentLoc *ArgsArray =
    const_cast<TemplateArgumentLoc*>(getTemplateArgs());
  for (unsigned I = 0, E = TArgs.size(); I != E; ++I)
    new (&ArgsArray[I]) TemplateArgumentLoc(TArgs[I]);
}

TemplateSpecializationKind FunctionDecl::getTemplateSpecializationKind() const {
  // For a function template specialization, query the specialization
  // information object.
  FunctionTemplateSpecializationInfo *FTSInfo
    = TemplateOrSpecialization.dyn_cast<FunctionTemplateSpecializationInfo*>();
  if (FTSInfo)
    return FTSInfo->getTemplateSpecializationKind();

  MemberSpecializationInfo *MSInfo
    = TemplateOrSpecialization.dyn_cast<MemberSpecializationInfo*>();
  if (MSInfo)
    return MSInfo->getTemplateSpecializationKind();
  
  return TSK_Undeclared;
}

void
FunctionDecl::setTemplateSpecializationKind(TemplateSpecializationKind TSK,
                                          SourceLocation PointOfInstantiation) {
  if (FunctionTemplateSpecializationInfo *FTSInfo
        = TemplateOrSpecialization.dyn_cast<
                                    FunctionTemplateSpecializationInfo*>()) {
    FTSInfo->setTemplateSpecializationKind(TSK);
    if (TSK != TSK_ExplicitSpecialization &&
        PointOfInstantiation.isValid() &&
        FTSInfo->getPointOfInstantiation().isInvalid())
      FTSInfo->setPointOfInstantiation(PointOfInstantiation);
  } else if (MemberSpecializationInfo *MSInfo
             = TemplateOrSpecialization.dyn_cast<MemberSpecializationInfo*>()) {
    MSInfo->setTemplateSpecializationKind(TSK);
    if (TSK != TSK_ExplicitSpecialization &&
        PointOfInstantiation.isValid() &&
        MSInfo->getPointOfInstantiation().isInvalid())
      MSInfo->setPointOfInstantiation(PointOfInstantiation);
  } else
    llvm_unreachable("Function cannot have a template specialization kind");
}

SourceLocation FunctionDecl::getPointOfInstantiation() const {
  if (FunctionTemplateSpecializationInfo *FTSInfo
        = TemplateOrSpecialization.dyn_cast<
                                        FunctionTemplateSpecializationInfo*>())
    return FTSInfo->getPointOfInstantiation();
  else if (MemberSpecializationInfo *MSInfo
             = TemplateOrSpecialization.dyn_cast<MemberSpecializationInfo*>())
    return MSInfo->getPointOfInstantiation();
  
  return SourceLocation();
}

bool FunctionDecl::isOutOfLine() const {
  if (Decl::isOutOfLine())
    return true;
  
  // If this function was instantiated from a member function of a 
  // class template, check whether that member function was defined out-of-line.
  if (FunctionDecl *FD = getInstantiatedFromMemberFunction()) {
    const FunctionDecl *Definition;
    if (FD->hasBody(Definition))
      return Definition->isOutOfLine();
  }
  
  // If this function was instantiated from a function template,
  // check whether that function template was defined out-of-line.
  if (FunctionTemplateDecl *FunTmpl = getPrimaryTemplate()) {
    const FunctionDecl *Definition;
    if (FunTmpl->getTemplatedDecl()->hasBody(Definition))
      return Definition->isOutOfLine();
  }
  
  return false;
}

SourceRange FunctionDecl::getSourceRange() const {
  return SourceRange(getOuterLocStart(), EndRangeLoc);
}

unsigned FunctionDecl::getMemoryFunctionKind() const {
  IdentifierInfo *FnInfo = getIdentifier();

  if (!FnInfo)
    return 0;
    
  // Builtin handling.
  switch (getBuiltinID()) {
  case Builtin::BI__builtin_memset:
  case Builtin::BI__builtin___memset_chk:
  case Builtin::BImemset:
    return Builtin::BImemset;

  case Builtin::BI__builtin_memcpy:
  case Builtin::BI__builtin___memcpy_chk:
  case Builtin::BImemcpy:
    return Builtin::BImemcpy;

  case Builtin::BI__builtin_memmove:
  case Builtin::BI__builtin___memmove_chk:
  case Builtin::BImemmove:
    return Builtin::BImemmove;

  case Builtin::BIstrlcpy:
  case Builtin::BI__builtin___strlcpy_chk:
    return Builtin::BIstrlcpy;

  case Builtin::BIstrlcat:
  case Builtin::BI__builtin___strlcat_chk:
    return Builtin::BIstrlcat;

  case Builtin::BI__builtin_memcmp:
  case Builtin::BImemcmp:
    return Builtin::BImemcmp;

  case Builtin::BI__builtin_strncpy:
  case Builtin::BI__builtin___strncpy_chk:
  case Builtin::BIstrncpy:
    return Builtin::BIstrncpy;

  case Builtin::BI__builtin_strncmp:
  case Builtin::BIstrncmp:
    return Builtin::BIstrncmp;

  case Builtin::BI__builtin_strncasecmp:
  case Builtin::BIstrncasecmp:
    return Builtin::BIstrncasecmp;

  case Builtin::BI__builtin_strncat:
  case Builtin::BI__builtin___strncat_chk:
  case Builtin::BIstrncat:
    return Builtin::BIstrncat;

  case Builtin::BI__builtin_strndup:
  case Builtin::BIstrndup:
    return Builtin::BIstrndup;

  case Builtin::BI__builtin_strlen:
  case Builtin::BIstrlen:
    return Builtin::BIstrlen;

  default:
    if (isExternC()) {
      if (FnInfo->isStr("memset"))
        return Builtin::BImemset;
      else if (FnInfo->isStr("memcpy"))
        return Builtin::BImemcpy;
      else if (FnInfo->isStr("memmove"))
        return Builtin::BImemmove;
      else if (FnInfo->isStr("memcmp"))
        return Builtin::BImemcmp;
      else if (FnInfo->isStr("strncpy"))
        return Builtin::BIstrncpy;
      else if (FnInfo->isStr("strncmp"))
        return Builtin::BIstrncmp;
      else if (FnInfo->isStr("strncasecmp"))
        return Builtin::BIstrncasecmp;
      else if (FnInfo->isStr("strncat"))
        return Builtin::BIstrncat;
      else if (FnInfo->isStr("strndup"))
        return Builtin::BIstrndup;
      else if (FnInfo->isStr("strlen"))
        return Builtin::BIstrlen;
    }
    break;
  }
  return 0;
}

//===----------------------------------------------------------------------===//
// FieldDecl Implementation
//===----------------------------------------------------------------------===//

FieldDecl *FieldDecl::Create(const ASTContext &C, DeclContext *DC,
                             SourceLocation StartLoc, SourceLocation IdLoc,
                             IdentifierInfo *Id, QualType T,
                             TypeSourceInfo *TInfo, Expr *BW, bool Mutable,
                             InClassInitStyle InitStyle) {
  return new (C, DC) FieldDecl(Decl::Field, DC, StartLoc, IdLoc, Id, T, TInfo,
                               BW, Mutable, InitStyle);
}

FieldDecl *FieldDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  return new (C, ID) FieldDecl(Field, nullptr, SourceLocation(),
                               SourceLocation(), nullptr, QualType(), nullptr,
                               nullptr, false, ICIS_NoInit);
}

bool FieldDecl::isAnonymousStructOrUnion() const {
  if (!isImplicit() || getDeclName())
    return false;

  if (const RecordType *Record = getType()->getAs<RecordType>())
    return Record->getDecl()->isAnonymousStructOrUnion();

  return false;
}

unsigned FieldDecl::getBitWidthValue(const ASTContext &Ctx) const {
  assert(isBitField() && "not a bitfield");
  Expr *BitWidth = static_cast<Expr *>(InitStorage.getPointer());
  return BitWidth->EvaluateKnownConstInt(Ctx).getZExtValue();
}

unsigned FieldDecl::getFieldIndex() const {
  const FieldDecl *Canonical = getCanonicalDecl();
  if (Canonical != this)
    return Canonical->getFieldIndex();

  if (CachedFieldIndex) return CachedFieldIndex - 1;

  unsigned Index = 0;
  const RecordDecl *RD = getParent();

  for (auto *Field : RD->fields()) {
    Field->getCanonicalDecl()->CachedFieldIndex = Index + 1;
    ++Index;
  }

  assert(CachedFieldIndex && "failed to find field in parent");
  return CachedFieldIndex - 1;
}

SourceRange FieldDecl::getSourceRange() const {
  switch (InitStorage.getInt()) {
  // All three of these cases store an optional Expr*.
  case ISK_BitWidthOrNothing:
  case ISK_InClassCopyInit:
  case ISK_InClassListInit:
    if (const Expr *E = static_cast<const Expr *>(InitStorage.getPointer()))
      return SourceRange(getInnerLocStart(), E->getLocEnd());
    // FALLTHROUGH

  case ISK_CapturedVLAType:
    return DeclaratorDecl::getSourceRange();
  }
  llvm_unreachable("bad init storage kind");
}

void FieldDecl::setCapturedVLAType(const VariableArrayType *VLAType) {
  assert((getParent()->isLambda() || getParent()->isCapturedRecord()) &&
         "capturing type in non-lambda or captured record.");
  assert(InitStorage.getInt() == ISK_BitWidthOrNothing &&
         InitStorage.getPointer() == nullptr &&
         "bit width, initializer or captured type already set");
  InitStorage.setPointerAndInt(const_cast<VariableArrayType *>(VLAType),
                               ISK_CapturedVLAType);
}

//===----------------------------------------------------------------------===//
// TagDecl Implementation
//===----------------------------------------------------------------------===//

SourceLocation TagDecl::getOuterLocStart() const {
  return getTemplateOrInnerLocStart(this);
}

SourceRange TagDecl::getSourceRange() const {
  SourceLocation E = RBraceLoc.isValid() ? RBraceLoc : getLocation();
  return SourceRange(getOuterLocStart(), E);
}

TagDecl *TagDecl::getCanonicalDecl() { return getFirstDecl(); }

void TagDecl::setTypedefNameForAnonDecl(TypedefNameDecl *TDD) {
  NamedDeclOrQualifier = TDD;
  if (const Type *T = getTypeForDecl()) {
    (void)T;
    assert(T->isLinkageValid());
  }
  assert(isLinkageValid());
}

void TagDecl::startDefinition() {
  IsBeingDefined = true;

  if (CXXRecordDecl *D = dyn_cast<CXXRecordDecl>(this)) {
    struct CXXRecordDecl::DefinitionData *Data =
      new (getASTContext()) struct CXXRecordDecl::DefinitionData(D);
    for (auto I : redecls())
      cast<CXXRecordDecl>(I)->DefinitionData = Data;
  }
}

void TagDecl::completeDefinition() {
  assert((!isa<CXXRecordDecl>(this) ||
          cast<CXXRecordDecl>(this)->hasDefinition()) &&
         "definition completed but not started");

  IsCompleteDefinition = true;
  IsBeingDefined = false;

  if (ASTMutationListener *L = getASTMutationListener())
    L->CompletedTagDefinition(this);
}

TagDecl *TagDecl::getDefinition() const {
  if (isCompleteDefinition())
    return const_cast<TagDecl *>(this);

  // If it's possible for us to have an out-of-date definition, check now.
  if (MayHaveOutOfDateDef) {
    if (IdentifierInfo *II = getIdentifier()) {
      if (II->isOutOfDate()) {
        updateOutOfDate(*II);
      }
    }
  }

  if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(this))
    return CXXRD->getDefinition();

  for (auto R : redecls())
    if (R->isCompleteDefinition())
      return R;

  return nullptr;
}

void TagDecl::setQualifierInfo(NestedNameSpecifierLoc QualifierLoc) {
  if (QualifierLoc) {
    // Make sure the extended qualifier info is allocated.
    if (!hasExtInfo())
      NamedDeclOrQualifier = new (getASTContext()) ExtInfo;
    // Set qualifier info.
    getExtInfo()->QualifierLoc = QualifierLoc;
  } else {
    // Here Qualifier == 0, i.e., we are removing the qualifier (if any).
    if (hasExtInfo()) {
      if (getExtInfo()->NumTemplParamLists == 0) {
        getASTContext().Deallocate(getExtInfo());
        NamedDeclOrQualifier = (TypedefNameDecl*)nullptr;
      }
      else
        getExtInfo()->QualifierLoc = QualifierLoc;
    }
  }
}

void TagDecl::setTemplateParameterListsInfo(ASTContext &Context,
                                            unsigned NumTPLists,
                                            TemplateParameterList **TPLists) {
  assert(NumTPLists > 0);
  // Make sure the extended decl info is allocated.
  if (!hasExtInfo())
    // Allocate external info struct.
    NamedDeclOrQualifier = new (getASTContext()) ExtInfo;
  // Set the template parameter lists info.
  getExtInfo()->setTemplateParameterListsInfo(Context, NumTPLists, TPLists);
}

//===----------------------------------------------------------------------===//
// EnumDecl Implementation
//===----------------------------------------------------------------------===//

void EnumDecl::anchor() { }

EnumDecl *EnumDecl::Create(ASTContext &C, DeclContext *DC,
                           SourceLocation StartLoc, SourceLocation IdLoc,
                           IdentifierInfo *Id,
                           EnumDecl *PrevDecl, bool IsScoped,
                           bool IsScopedUsingClassTag, bool IsFixed) {
  EnumDecl *Enum = new (C, DC) EnumDecl(C, DC, StartLoc, IdLoc, Id, PrevDecl,
                                        IsScoped, IsScopedUsingClassTag,
                                        IsFixed);
  Enum->MayHaveOutOfDateDef = C.getLangOpts().Modules;
  C.getTypeDeclType(Enum, PrevDecl);
  return Enum;
}

EnumDecl *EnumDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  EnumDecl *Enum =
      new (C, ID) EnumDecl(C, nullptr, SourceLocation(), SourceLocation(),
                           nullptr, nullptr, false, false, false);
  Enum->MayHaveOutOfDateDef = C.getLangOpts().Modules;
  return Enum;
}

SourceRange EnumDecl::getIntegerTypeRange() const {
  if (const TypeSourceInfo *TI = getIntegerTypeSourceInfo())
    return TI->getTypeLoc().getSourceRange();
  return SourceRange();
}

void EnumDecl::completeDefinition(QualType NewType,
                                  QualType NewPromotionType,
                                  unsigned NumPositiveBits,
                                  unsigned NumNegativeBits) {
  assert(!isCompleteDefinition() && "Cannot redefine enums!");
  if (!IntegerType)
    IntegerType = NewType.getTypePtr();
  PromotionType = NewPromotionType;
  setNumPositiveBits(NumPositiveBits);
  setNumNegativeBits(NumNegativeBits);
  TagDecl::completeDefinition();
}

TemplateSpecializationKind EnumDecl::getTemplateSpecializationKind() const {
  if (MemberSpecializationInfo *MSI = getMemberSpecializationInfo())
    return MSI->getTemplateSpecializationKind();

  return TSK_Undeclared;
}

void EnumDecl::setTemplateSpecializationKind(TemplateSpecializationKind TSK,
                                         SourceLocation PointOfInstantiation) {
  MemberSpecializationInfo *MSI = getMemberSpecializationInfo();
  assert(MSI && "Not an instantiated member enumeration?");
  MSI->setTemplateSpecializationKind(TSK);
  if (TSK != TSK_ExplicitSpecialization &&
      PointOfInstantiation.isValid() &&
      MSI->getPointOfInstantiation().isInvalid())
    MSI->setPointOfInstantiation(PointOfInstantiation);
}

EnumDecl *EnumDecl::getInstantiatedFromMemberEnum() const {
  if (SpecializationInfo)
    return cast<EnumDecl>(SpecializationInfo->getInstantiatedFrom());

  return nullptr;
}

void EnumDecl::setInstantiationOfMemberEnum(ASTContext &C, EnumDecl *ED,
                                            TemplateSpecializationKind TSK) {
  assert(!SpecializationInfo && "Member enum is already a specialization");
  SpecializationInfo = new (C) MemberSpecializationInfo(ED, TSK);
}

//===----------------------------------------------------------------------===//
// RecordDecl Implementation
//===----------------------------------------------------------------------===//

RecordDecl::RecordDecl(Kind DK, TagKind TK, const ASTContext &C,
                       DeclContext *DC, SourceLocation StartLoc,
                       SourceLocation IdLoc, IdentifierInfo *Id,
                       RecordDecl *PrevDecl)
    : TagDecl(DK, TK, C, DC, IdLoc, Id, PrevDecl, StartLoc) {
  HasFlexibleArrayMember = false;
  AnonymousStructOrUnion = false;
  HasObjectMember = false;
  HasVolatileMember = false;
  LoadedFieldsFromExternalStorage = false;
  assert(classof(static_cast<Decl*>(this)) && "Invalid Kind!");
}

RecordDecl *RecordDecl::Create(const ASTContext &C, TagKind TK, DeclContext *DC,
                               SourceLocation StartLoc, SourceLocation IdLoc,
                               IdentifierInfo *Id, RecordDecl* PrevDecl) {
  RecordDecl *R = new (C, DC) RecordDecl(Record, TK, C, DC,
                                         StartLoc, IdLoc, Id, PrevDecl);
  R->MayHaveOutOfDateDef = C.getLangOpts().Modules;

  C.getTypeDeclType(R, PrevDecl);
  return R;
}

RecordDecl *RecordDecl::CreateDeserialized(const ASTContext &C, unsigned ID) {
  RecordDecl *R =
      new (C, ID) RecordDecl(Record, TTK_Struct, C, nullptr, SourceLocation(),
                             SourceLocation(), nullptr, nullptr);
  R->MayHaveOutOfDateDef = C.getLangOpts().Modules;
  return R;
}

bool RecordDecl::isInjectedClassName() const {
  return isImplicit() && getDeclName() && getDeclContext()->isRecord() &&
    cast<RecordDecl>(getDeclContext())->getDeclName() == getDeclName();
}

bool RecordDecl::isLambda() const {
  if (auto RD = dyn_cast<CXXRecordDecl>(this))
    return RD->isLambda();
  return false;
}

bool RecordDecl::isCapturedRecord() const {
  return hasAttr<CapturedRecordAttr>();
}

void RecordDecl::setCapturedRecord() {
  addAttr(CapturedRecordAttr::CreateImplicit(getASTContext()));
}

RecordDecl::field_iterator RecordDecl::field_begin() const {
  if (hasExternalLexicalStorage() && !LoadedFieldsFromExternalStorage)
    LoadFieldsFromExternalStorage();

  return field_iterator(decl_iterator(FirstDecl));
}

/// completeDefinition - Notes that the definition of this type is now
/// complete.
void RecordDecl::completeDefinition() {
  assert(!isCompleteDefinition() && "Cannot redefine record!");
  TagDecl::completeDefinition();
}

/// isMsStruct - Get whether or not this record uses ms_struct layout.
/// This which can be turned on with an attribute, pragma, or the
/// -mms-bitfields command-line option.
bool RecordDecl::isMsStruct(const ASTContext &C) const {
  return hasAttr<MSStructAttr>() || C.getLangOpts().MSBitfields == 1;
}

static bool isFieldOrIndirectField(Decl::Kind K) {
  return FieldDecl::classofKind(K) || IndirectFieldDecl::classofKind(K);
}

void RecordDecl::LoadFieldsFromExternalStorage() const {
  ExternalASTSource *Source = getASTContext().getExternalSource();
  assert(hasExternalLexicalStorage() && Source && "No external storage?");

  // Notify that we have a RecordDecl doing some initialization.
  ExternalASTSource::Deserializing TheFields(Source);

  SmallVector<Decl*, 64> Decls;
  LoadedFieldsFromExternalStorage = true;  
  switch (Source->FindExternalLexicalDecls(this, isFieldOrIndirectField,
                                           Decls)) {
  case ELR_Success:
    break;
    
  case ELR_AlreadyLoaded:
  case ELR_Failure:
    return;
  }

#ifndef NDEBUG
  // Check that all decls we got were FieldDecls.
  for (unsigned i=0, e=Decls.size(); i != e; ++i)
    assert(isa<FieldDecl>(Decls[i]) || isa<IndirectFieldDecl>(Decls[i]));
#endif

  if (Decls.empty())
    return;

  std::tie(FirstDecl, LastDecl) = BuildDeclChain(Decls,
                                                 /*FieldsAlreadyLoaded=*/false);
}

bool RecordDecl::mayInsertExtraPadding(bool EmitRemark) const {
  ASTContext &Context = getASTContext();
  if (!Context.getLangOpts().Sanitize.has(SanitizerKind::Address) ||
      !Context.getLangOpts().SanitizeAddressFieldPadding)
    return false;
  const auto &Blacklist = Context.getSanitizerBlacklist();
  const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(this);
  // We may be able to relax some of these requirements.
  int ReasonToReject = -1;
  if (!CXXRD || CXXRD->isExternCContext())
    ReasonToReject = 0;  // is not C++.
  else if (CXXRD->hasAttr<PackedAttr>())
    ReasonToReject = 1;  // is packed.
  else if (CXXRD->isUnion())
    ReasonToReject = 2;  // is a union.
  else if (CXXRD->isTriviallyCopyable())
    ReasonToReject = 3;  // is trivially copyable.
  else if (CXXRD->hasTrivialDestructor())
    ReasonToReject = 4;  // has trivial destructor.
  else if (CXXRD->isStandardLayout())
    ReasonToReject = 5;  // is standard layout.
  else if (Blacklist.isBlacklistedLocation(getLocation(), "field-padding"))
    ReasonToReject = 6;  // is in a blacklisted file.
  else if (Blacklist.isBlacklistedType(getQualifiedNameAsString(),
                                       "field-padding"))
    ReasonToReject = 7;  // is blacklisted.

  if (EmitRemark) {
    if (ReasonToReject >= 0)
      Context.getDiagnostics().Report(
          getLocation(),
          diag::remark_sanitize_address_insert_extra_padding_rejected)
          << getQualifiedNameAsString() << ReasonToReject;
    else
      Context.getDiagnostics().Report(
          getLocation(),
          diag::remark_sanitize_address_insert_extra_padding_accepted)
          << getQualifiedNameAsString();
  }
  return ReasonToReject < 0;
}

const FieldDecl *RecordDecl::findFirstNamedDataMember() const {
  for (const auto *I : fields()) {
    if (I->getIdentifier())
      return I;

    if (const RecordType *RT = I->getType()->getAs<RecordType>())
      if (const FieldDecl *NamedDataMember =
          RT->getDecl()->findFirstNamedDataMember())
        return NamedDataMember;
  }

  // We didn't find a named data member.
  return nullptr;
}


//===----------------------------------------------------------------------===//
// BlockDecl Implementation
//===----------------------------------------------------------------------===//

void BlockDecl::setParams(ArrayRef<ParmVarDecl *> NewParamInfo) {
  assert(!ParamInfo && "Already has param info!");

  // Zero params -> null pointer.
  if (!NewParamInfo.empty()) {
    NumParams = NewParamInfo.size();
    ParamInfo = new (getASTContext()) ParmVarDecl*[NewParamInfo.size()];
    std::copy(NewParamInfo.begin(), NewParamInfo.end(), ParamInfo);
  }
}

void BlockDecl::setCaptures(ASTContext &Context,
                            const Capture *begin,
                            const Capture *end,
                            bool capturesCXXThis) {
  CapturesCXXThis = capturesCXXThis;

  if (begin == end) {
    NumCaptures = 0;
    Captures = nullptr;
    return;
  }

  NumCaptures = end - begin;

  // Avoid new Capture[] because we don't want to provide a default
  // constructor.
  size_t allocationSize = NumCaptures * sizeof(Capture);
  void *buffer = Context.Allocate(allocationSize, /*alignment*/sizeof(void*));
  memcpy(buffer, begin, allocationSize);
  Captures = static_cast<Capture*>(buffer);
}

bool BlockDecl::capturesVariable(const VarDecl *variable) const {
  for (const auto &I : captures())
    // Only auto vars can be captured, so no redeclaration worries.
    if (I.getVariable() == variable)
      return true;

  return false;
}

SourceRange BlockDecl::getSourceRange() const {
  return SourceRange(getLocation(), Body? Body->getLocEnd() : getLocation());
}

//===----------------------------------------------------------------------===//
// Other Decl Allocation/Deallocation Method Implementations
//===----------------------------------------------------------------------===//

void TranslationUnitDecl::anchor() { }

TranslationUnitDecl *TranslationUnitDecl::Create(ASTContext &C) {
  return new (C, (DeclContext *)nullptr) TranslationUnitDecl(C);
}

void ExternCContextDecl::anchor() { }

ExternCContextDecl *ExternCContextDecl::Create(const ASTContext &C,
                                               TranslationUnitDecl *DC) {
  return new (C, DC) ExternCContextDecl(DC);
}

void LabelDecl::anchor() { }

LabelDecl *LabelDecl::Create(ASTContext &C, DeclContext *DC,
                             SourceLocation IdentL, IdentifierInfo *II) {
  return new (C, DC) LabelDecl(DC, IdentL, II, nullptr, IdentL);
}

LabelDecl *LabelDecl::Create(ASTContext &C, DeclContext *DC,
                             SourceLocation IdentL, IdentifierInfo *II,
                             SourceLocation GnuLabelL) {
  assert(GnuLabelL != IdentL && "Use this only for GNU local labels");
  return new (C, DC) LabelDecl(DC, IdentL, II, nullptr, GnuLabelL);
}

LabelDecl *LabelDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  return new (C, ID) LabelDecl(nullptr, SourceLocation(), nullptr, nullptr,
                               SourceLocation());
}

void LabelDecl::setMSAsmLabel(StringRef Name) {
  char *Buffer = new (getASTContext(), 1) char[Name.size() + 1];
  memcpy(Buffer, Name.data(), Name.size());
  Buffer[Name.size()] = '\0';
  MSAsmName = Buffer;
}

void ValueDecl::anchor() { }

bool ValueDecl::isWeak() const {
  for (const auto *I : attrs())
    if (isa<WeakAttr>(I) || isa<WeakRefAttr>(I))
      return true;

  return isWeakImported();
}

void ImplicitParamDecl::anchor() { }

ImplicitParamDecl *ImplicitParamDecl::Create(ASTContext &C, DeclContext *DC,
                                             SourceLocation IdLoc,
                                             IdentifierInfo *Id,
                                             QualType Type) {
  return new (C, DC) ImplicitParamDecl(C, DC, IdLoc, Id, Type);
}

ImplicitParamDecl *ImplicitParamDecl::CreateDeserialized(ASTContext &C,
                                                         unsigned ID) {
  return new (C, ID) ImplicitParamDecl(C, nullptr, SourceLocation(), nullptr,
                                       QualType());
}

FunctionDecl *FunctionDecl::Create(ASTContext &C, DeclContext *DC,
                                   SourceLocation StartLoc,
                                   const DeclarationNameInfo &NameInfo,
                                   QualType T, TypeSourceInfo *TInfo,
                                   StorageClass SC,
                                   bool isInlineSpecified,
                                   bool hasWrittenPrototype,
                                   bool isConstexprSpecified) {
  FunctionDecl *New =
      new (C, DC) FunctionDecl(Function, C, DC, StartLoc, NameInfo, T, TInfo,
                               SC, isInlineSpecified, isConstexprSpecified);
  New->HasWrittenPrototype = hasWrittenPrototype;
  return New;
}

FunctionDecl *FunctionDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  return new (C, ID) FunctionDecl(Function, C, nullptr, SourceLocation(),
                                  DeclarationNameInfo(), QualType(), nullptr,
                                  SC_None, false, false);
}

BlockDecl *BlockDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation L) {
  return new (C, DC) BlockDecl(DC, L);
}

BlockDecl *BlockDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  return new (C, ID) BlockDecl(nullptr, SourceLocation());
}

CapturedDecl *CapturedDecl::Create(ASTContext &C, DeclContext *DC,
                                   unsigned NumParams) {
  return new (C, DC, NumParams * sizeof(ImplicitParamDecl *))
      CapturedDecl(DC, NumParams);
}

CapturedDecl *CapturedDecl::CreateDeserialized(ASTContext &C, unsigned ID,
                                               unsigned NumParams) {
  return new (C, ID, NumParams * sizeof(ImplicitParamDecl *))
      CapturedDecl(nullptr, NumParams);
}

EnumConstantDecl *EnumConstantDecl::Create(ASTContext &C, EnumDecl *CD,
                                           SourceLocation L,
                                           IdentifierInfo *Id, QualType T,
                                           Expr *E, const llvm::APSInt &V) {
  return new (C, CD) EnumConstantDecl(CD, L, Id, T, E, V);
}

EnumConstantDecl *
EnumConstantDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  return new (C, ID) EnumConstantDecl(nullptr, SourceLocation(), nullptr,
                                      QualType(), nullptr, llvm::APSInt());
}

void IndirectFieldDecl::anchor() { }

IndirectFieldDecl *
IndirectFieldDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation L,
                          IdentifierInfo *Id, QualType T, NamedDecl **CH,
                          unsigned CHS) {
  return new (C, DC) IndirectFieldDecl(DC, L, Id, T, CH, CHS);
}

IndirectFieldDecl *IndirectFieldDecl::CreateDeserialized(ASTContext &C,
                                                         unsigned ID) {
  return new (C, ID) IndirectFieldDecl(nullptr, SourceLocation(),
                                       DeclarationName(), QualType(), nullptr,
                                       0);
}

SourceRange EnumConstantDecl::getSourceRange() const {
  SourceLocation End = getLocation();
  if (Init)
    End = Init->getLocEnd();
  return SourceRange(getLocation(), End);
}

void TypeDecl::anchor() { }

TypedefDecl *TypedefDecl::Create(ASTContext &C, DeclContext *DC,
                                 SourceLocation StartLoc, SourceLocation IdLoc,
                                 IdentifierInfo *Id, TypeSourceInfo *TInfo) {
  return new (C, DC) TypedefDecl(C, DC, StartLoc, IdLoc, Id, TInfo);
}

void TypedefNameDecl::anchor() { }

TagDecl *TypedefNameDecl::getAnonDeclWithTypedefName(bool AnyRedecl) const {
  if (auto *TT = getTypeSourceInfo()->getType()->getAs<TagType>()) {
    auto *OwningTypedef = TT->getDecl()->getTypedefNameForAnonDecl();
    auto *ThisTypedef = this;
    if (AnyRedecl && OwningTypedef) {
      OwningTypedef = OwningTypedef->getCanonicalDecl();
      ThisTypedef = ThisTypedef->getCanonicalDecl();
    }
    if (OwningTypedef == ThisTypedef)
      return TT->getDecl();
  }

  return nullptr;
}

TypedefDecl *TypedefDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  return new (C, ID) TypedefDecl(C, nullptr, SourceLocation(), SourceLocation(),
                                 nullptr, nullptr);
}

TypeAliasDecl *TypeAliasDecl::Create(ASTContext &C, DeclContext *DC,
                                     SourceLocation StartLoc,
                                     SourceLocation IdLoc, IdentifierInfo *Id,
                                     TypeSourceInfo *TInfo) {
  return new (C, DC) TypeAliasDecl(C, DC, StartLoc, IdLoc, Id, TInfo);
}

TypeAliasDecl *TypeAliasDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  return new (C, ID) TypeAliasDecl(C, nullptr, SourceLocation(),
                                   SourceLocation(), nullptr, nullptr);
}

SourceRange TypedefDecl::getSourceRange() const {
  SourceLocation RangeEnd = getLocation();
  if (TypeSourceInfo *TInfo = getTypeSourceInfo()) {
    if (typeIsPostfix(TInfo->getType()))
      RangeEnd = TInfo->getTypeLoc().getSourceRange().getEnd();
  }
  return SourceRange(getLocStart(), RangeEnd);
}

SourceRange TypeAliasDecl::getSourceRange() const {
  SourceLocation RangeEnd = getLocStart();
  if (TypeSourceInfo *TInfo = getTypeSourceInfo())
    RangeEnd = TInfo->getTypeLoc().getSourceRange().getEnd();
  return SourceRange(getLocStart(), RangeEnd);
}

void FileScopeAsmDecl::anchor() { }

FileScopeAsmDecl *FileScopeAsmDecl::Create(ASTContext &C, DeclContext *DC,
                                           StringLiteral *Str,
                                           SourceLocation AsmLoc,
                                           SourceLocation RParenLoc) {
  return new (C, DC) FileScopeAsmDecl(DC, Str, AsmLoc, RParenLoc);
}

FileScopeAsmDecl *FileScopeAsmDecl::CreateDeserialized(ASTContext &C,
                                                       unsigned ID) {
  return new (C, ID) FileScopeAsmDecl(nullptr, nullptr, SourceLocation(),
                                      SourceLocation());
}

void EmptyDecl::anchor() {}

EmptyDecl *EmptyDecl::Create(ASTContext &C, DeclContext *DC, SourceLocation L) {
  return new (C, DC) EmptyDecl(DC, L);
}

EmptyDecl *EmptyDecl::CreateDeserialized(ASTContext &C, unsigned ID) {
  return new (C, ID) EmptyDecl(nullptr, SourceLocation());
}

//===----------------------------------------------------------------------===//
// ImportDecl Implementation
//===----------------------------------------------------------------------===//

/// \brief Retrieve the number of module identifiers needed to name the given
/// module.
static unsigned getNumModuleIdentifiers(Module *Mod) {
  unsigned Result = 1;
  while (Mod->Parent) {
    Mod = Mod->Parent;
    ++Result;
  }
  return Result;
}

ImportDecl::ImportDecl(DeclContext *DC, SourceLocation StartLoc, 
                       Module *Imported,
                       ArrayRef<SourceLocation> IdentifierLocs)
  : Decl(Import, DC, StartLoc), ImportedAndComplete(Imported, true),
    NextLocalImport()
{
  assert(getNumModuleIdentifiers(Imported) == IdentifierLocs.size());
  SourceLocation *StoredLocs = reinterpret_cast<SourceLocation *>(this + 1);
  memcpy(StoredLocs, IdentifierLocs.data(), 
         IdentifierLocs.size() * sizeof(SourceLocation));
}

ImportDecl::ImportDecl(DeclContext *DC, SourceLocation StartLoc, 
                       Module *Imported, SourceLocation EndLoc)
  : Decl(Import, DC, StartLoc), ImportedAndComplete(Imported, false),
    NextLocalImport()
{
  *reinterpret_cast<SourceLocation *>(this + 1) = EndLoc;
}

ImportDecl *ImportDecl::Create(ASTContext &C, DeclContext *DC,
                               SourceLocation StartLoc, Module *Imported,
                               ArrayRef<SourceLocation> IdentifierLocs) {
  return new (C, DC, IdentifierLocs.size() * sizeof(SourceLocation))
      ImportDecl(DC, StartLoc, Imported, IdentifierLocs);
}

ImportDecl *ImportDecl::CreateImplicit(ASTContext &C, DeclContext *DC,
                                       SourceLocation StartLoc,
                                       Module *Imported,
                                       SourceLocation EndLoc) {
  ImportDecl *Import =
      new (C, DC, sizeof(SourceLocation)) ImportDecl(DC, StartLoc,
                                                     Imported, EndLoc);
  Import->setImplicit();
  return Import;
}

ImportDecl *ImportDecl::CreateDeserialized(ASTContext &C, unsigned ID,
                                           unsigned NumLocations) {
  return new (C, ID, NumLocations * sizeof(SourceLocation))
      ImportDecl(EmptyShell());
}

ArrayRef<SourceLocation> ImportDecl::getIdentifierLocs() const {
  if (!ImportedAndComplete.getInt())
    return None;

  const SourceLocation *StoredLocs
    = reinterpret_cast<const SourceLocation *>(this + 1);
  return llvm::makeArrayRef(StoredLocs,
                            getNumModuleIdentifiers(getImportedModule()));
}

SourceRange ImportDecl::getSourceRange() const {
  if (!ImportedAndComplete.getInt())
    return SourceRange(getLocation(), 
                       *reinterpret_cast<const SourceLocation *>(this + 1));
  
  return SourceRange(getLocation(), getIdentifierLocs().back());
}