[cpp.predefined]p2:
__STDCPP_THREADS__
Defined, and has the value integer literal 1, if and only if a program
can have more than one thread of execution .
Also define it only if it's not defined already, since it's supposed
to be defined by the compiler.
Also move it from thread to __config (which requires setting it only
if _LIBCPP_HAS_NO_THREADS is not defined).
Part of PR33230. The intent is to eventually make the compiler define
this instead.
llvm-svn: 367316
_LIBCPP_HAS_NO_THREADS is defined.
#endif
+#if defined(__STDCPP_THREADS__) && defined(_LIBCPP_HAS_NO_THREADS)
+#error _LIBCPP_HAS_NO_THREADS cannot be set when __STDCPP_THREADS__ is set.
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_THREADS) && !defined(__STDCPP_THREADS__)
+#define __STDCPP_THREADS__ 1
+#endif
+
// The glibc and Bionic implementation of pthreads implements
// pthread_mutex_destroy as nop for regular mutexes. Additionally, Win32
// mutexes have no destroy mechanism.
thread synopsis
-#define __STDCPP_THREADS__ __cplusplus
-
namespace std
{
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
-#define __STDCPP_THREADS__ __cplusplus
-
#ifdef _LIBCPP_HAS_NO_THREADS
#error <thread> is not supported on this single threaded system
#else // !_LIBCPP_HAS_NO_THREADS
// <thread>
-// #define __STDCPP_THREADS__ __cplusplus
+// #define __STDCPP_THREADS__ 1
#include <thread>
{
#ifndef __STDCPP_THREADS__
#error __STDCPP_THREADS__ is not defined
+#elif __STDCPP_THREADS__ != 1
+#error __STDCPP_THREADS__ has the wrong value
#endif
return 0;