https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64638
Hans-Peter Nilsson <hp at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |redi at gcc dot gnu.org --- Comment #2 from Hans-Peter Nilsson <hp at gcc dot gnu.org> --- At the risk of waving a red herring, in revision r219770, I see: +++ libstdc++-v3/include/bits/atomic_futex.h (revision 219770) ... +#if !defined(_GLIBCXX_HAVE_LINUX_FUTEX) +#include <mutex> +#include <condition_variable> +#endif (no guard _GLIBCXX_HAS_GTHREADS) but in include/std/condition_variable and mutex, respectively #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) ... #ifdef _GLIBCXX_HAS_GTHREADS around the interesting bits (class mutex etc.) and in the build log: checking for gthreads library... no so, is a #ifdef _GLIBCXX_HAS_GTHREADS just missing from atomic_futex.h (or some similar missing guard)? CC:ing reviewer.