C11 defines `kill_dependency` as a macro in <stdatomic.h>. When you
include <atomic> after <stdatomic.h>, the macro clashes with
`std::kill_dependency` and causes multiple errors. Explicit error should
help in diagnosing those errors.
No change for working code that includes <atomic> before <stdatomic.h>.
rdar://problem/
27435938
Reviewers: rsmith, EricWF, mclow.lists, jfb
Reviewed By: jfb
Subscribers: jfb, jkorous-apple, christof, bumblebritches57, JonChesterfield, smeenai, cfe-commits
Differential Revision: https://reviews.llvm.org/D45470
llvm-svn: 332413
#if !defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_GCC_ATOMIC_IMP)
#error <atomic> is not implemented
#endif
+#ifdef kill_dependency
+#error C++ standard library is incompatible with <stdatomic.h>
+#endif
#if _LIBCPP_STD_VER > 14
# define __cpp_lib_atomic_is_always_lock_free 201603L