When installing a mingw-w64 toolchain (for example, via `crossdev i686-w64-mingw32` or the like) one will end up with: i686-w64-mingw32-gcc -v Using built-in specs. COLLECT_GCC=i686-w64-mingw32-gcc COLLECT_LTO_WRAPPER=/usr/libexec/gcc/i686-w64-mingw32/6.4.0/lto-wrapper Target: i686-w64-mingw32 Configured with: ..... Thread model: win32 gcc version 6.4.0 (Gentoo 6.4.0 p1.0) One can manually use `EXTRA_ECONF="--enable-threads=posix" emerge -1 cross-i686-w64-mingw32/gcc` after rebuilding cross-i686-w64-mingw32/mingw64-runtime with USE=libraries (to get the pthread dlls) in order to obtain 'Thread model: posix' It would be of use to either provide a USE flag for sys-devel/gcc to enable posix threads for mingw-w64 or just explicitly set the configure flag after the initial bootstrap.
*** Bug 760018 has been marked as a duplicate of this bug. ***
*** Bug 669856 has been marked as a duplicate of this bug. ***
*** Bug 766821 has been marked as a duplicate of this bug. ***
Is this still relevant?