1 files changed, 59 insertions, 19 deletions
diff --git a/contrib/llvm-project/clang/lib/Headers/stdarg.h b/contrib/llvm-project/clang/lib/Headers/stdarg.h
index 0bc39408c1e5..6203d7a600a2 100644
--- a/contrib/llvm-project/clang/lib/Headers/stdarg.h
+++ b/contrib/llvm-project/clang/lib/Headers/stdarg.h
@@ -7,29 +7,69 @@
  *===-----------------------------------------------------------------------===
  */
 
-#ifndef __STDARG_H
-#define __STDARG_H
-
-#ifndef _VA_LIST
-typedef __builtin_va_list va_list;
-#define _VA_LIST
-#endif
-#define va_start(ap, param) __builtin_va_start(ap, param)
-#define va_end(ap)          __builtin_va_end(ap)
-#define va_arg(ap, type)    __builtin_va_arg(ap, type)
+/*
+ * This header is designed to be included multiple times. If any of the __need_
+ * macros are defined, then only that subset of interfaces are provided. This
+ * can be useful for POSIX headers that need to not expose all of stdarg.h, but
+ * need to use some of its interfaces. Otherwise this header provides all of
+ * the expected interfaces.
+ *
+ * When clang modules are enabled, this header is a textual header to support
+ * the multiple include behavior. As such, it doesn't directly declare anything
+ * so that it doesn't add duplicate declarations to all of its includers'
+ * modules.
+ */
+#if defined(__MVS__) && __has_include_next(<stdarg.h>)
+#undef __need___va_list
+#undef __need_va_list
+#undef __need_va_arg
+#undef __need___va_copy
+#undef __need_va_copy
+#include <__stdarg_header_macro.h>
+#include_next <stdarg.h>
 
+#else
+#if !defined(__need___va_list) && !defined(__need_va_list) &&                  \
+    !defined(__need_va_arg) && !defined(__need___va_copy) &&                   \
+    !defined(__need_va_copy)
+#define __need___va_list
+#define __need_va_list
+#define __need_va_arg
+#define __need___va_copy
 /* GCC always defines __va_copy, but does not define va_copy unless in c99 mode
  * or -ansi is not specified, since it was not part of C90.
  */
-#define __va_copy(d,s) __builtin_va_copy(d,s)
-
-#if __STDC_VERSION__ >= 199901L || __cplusplus >= 201103L || !defined(__STRICT_ANSI__)
-#define va_copy(dest, src)  __builtin_va_copy(dest, src)
+#if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) ||              \
+    (defined(__cplusplus) && __cplusplus >= 201103L) ||                        \
+    !defined(__STRICT_ANSI__)
+#define __need_va_copy
 #endif
-
-#ifndef __GNUC_VA_LIST
-#define __GNUC_VA_LIST 1
-typedef __builtin_va_list __gnuc_va_list;
+#include <__stdarg_header_macro.h>
 #endif
 
-#endif /* __STDARG_H */
+#ifdef __need___va_list
+#include <__stdarg___gnuc_va_list.h>
+#undef __need___va_list
+#endif /* defined(__need___va_list) */
+
+#ifdef __need_va_list
+#include <__stdarg_va_list.h>
+#undef __need_va_list
+#endif /* defined(__need_va_list) */
+
+#ifdef __need_va_arg
+#include <__stdarg_va_arg.h>
+#undef __need_va_arg
+#endif /* defined(__need_va_arg) */
+
+#ifdef __need___va_copy
+#include <__stdarg___va_copy.h>
+#undef __need___va_copy
+#endif /* defined(__need___va_copy) */
+
+#ifdef __need_va_copy
+#include <__stdarg_va_copy.h>
+#undef __need_va_copy
+#endif /* defined(__need_va_copy) */
+
+#endif /* __MVS__ */