clang/test/Sema/builtin-memcpy.c

   1 // RUN: %clang_cc1 %s -triple x86_64-unknown-linux -fsyntax-only -verify=c
   2 // RUN: %clang_cc1 -x c++ %s -triple x86_64-unknown-linux -fsyntax-only -verify=cxx
   3
   4 // cxx-no-diagnostics
   5
   6
   7 /// Zero-sized structs should not crash.
   8 int b() {
   9   struct {      } a[10];
  10   __builtin_memcpy(&a[2], a, 2); // c-warning {{buffer has size 0, but size argument is 2}}
  11   return 0;
  12 }
  13
  14 #ifdef __cplusplus
  15 // FIXME: This is UB and GCC correctly diagnoses it. Clang should do the same.
  16 constexpr int b2() {
  17   struct {      } a[10];
  18   __builtin_memcpy(&a[2], a, 2);
  19   return 0;
  20 }
  21 static_assert(b2() == 0, "");
  22 #endif