Re: [PATCH] c++: Predefine __STDCPP_THREADS__ in the compiler if thread model is not single

[Jason Merrill via Gcc-patches]

On 11/13/20 2:20 PM, Tom Tromey wrote:
"Jakub" == Jakub Jelinek via Gcc-patches <gcc-patches@gcc.gnu.org> writes:

Jakub> 2020-11-13  Jakub Jelinek  <ja...@redhat.com>

Jakub>       * c-cppbuiltin.c: Include configargs.h.
Jakub>       (c_cpp_builtins): For C++11 and later if THREAD_MODEL_SPEC is not
Jakub>       defined, predefine __STDCPP_THREADS__ to 1 unless thread_model is
Jakub>       "single".

Note this is https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63287

Any opinions about the relative advantage of doing this in the compiler 
vs. doing it in the library, as in Jonathan's patch in the PR?

Jason