1 files changed, 96 insertions, 0 deletions
diff --git a/test/Parser/extra-semi-resulting-in-nullstmt.cpp b/test/Parser/extra-semi-resulting-in-nullstmt.cpp
new file mode 100644
index 000000000000..a09d942c5892
--- /dev/null
+++ b/test/Parser/extra-semi-resulting-in-nullstmt.cpp
@@ -0,0 +1,96 @@
+// RUN: %clang_cc1 -fsyntax-only -Wextra-semi-stmt -verify %s
+// RUN: cp %s %t
+// RUN: %clang_cc1 -x c++ -Wextra-semi-stmt -fixit %t
+// RUN: %clang_cc1 -x c++ -Wextra-semi-stmt -Werror %t
+
+#define GOODMACRO(varname) int varname
+#define BETTERMACRO(varname) GOODMACRO(varname);
+#define NULLMACRO(varname)
+
+enum MyEnum {
+  E1,
+  E2
+};
+
+void test() {
+  ; // expected-warning {{empty expression statement has no effect; remove unnecessary ';' to silence this warning}}
+  ;
+
+  // This removal of extra semi also consumes all the comments.
+  // clang-format: off
+  ;;;
+  // clang-format: on
+
+  // clang-format: off
+  ;NULLMACRO(ZZ);
+  // clang-format: on
+
+  {}; // expected-warning {{empty expression statement has no effect; remove unnecessary ';' to silence this warning}}
+
+  {
+    ; // expected-warning {{empty expression statement has no effect; remove unnecessary ';' to silence this warning}}
+  }
+
+  if (true) {
+    ; // expected-warning {{empty expression statement has no effect; remove unnecessary ';' to silence this warning}}
+  }
+
+  GOODMACRO(v0); // OK
+
+  GOODMACRO(v1;) // OK
+
+  BETTERMACRO(v2) // OK
+
+  BETTERMACRO(v3;) // Extra ';', but within macro expansion, so ignored.
+
+  BETTERMACRO(v4); // expected-warning {{empty expression statement has no effect; remove unnecessary ';' to silence this warning}}
+
+  BETTERMACRO(v5;); // expected-warning {{empty expression statement has no effect; remove unnecessary ';' to silence this warning}}
+
+  NULLMACRO(v6) // OK
+
+  NULLMACRO(v7); // OK. This could be either GOODMACRO() or BETTERMACRO() situation, so we can't know we can drop it.
+
+  if (true)
+    ; // OK
+
+  while (true)
+    ; // OK
+
+  do
+    ; // OK
+  while (true);
+
+  for (;;) // OK
+    ;      // OK
+
+  MyEnum my_enum;
+  switch (my_enum) {
+  case E1:
+    // stuff
+    break;
+  case E2:; // OK
+  }
+
+  for (;;) {
+    for (;;) {
+      goto contin_outer;
+    }
+  contin_outer:; // OK
+  }
+}
+
+;
+
+namespace NS {};
+
+void foo(int x) {
+  switch (x) {
+  case 0:
+    [[fallthrough]];
+  case 1:
+    return;
+  }
+}
+
+[[]];