[Mingw-w64-public] [PATCH] Use __builtin_frame_address on Clang.

Ruby was running into a crash calling longjmp on a jmp_buf obtained by calling setjmp from a function that had previously called alloca. This was resulting in mingw_getsp returning the *current* SP rather than the "frame address"/"base pointer" for the frame. This caused longjmp to raise STATUS_B

Re: [Mingw-w64-public] Native TLS

2021-08-01 19:13 (UTC-0700), Jeremy Drake via Mingw-w64-public: > On Mon, 2 Aug 2021, Dmitry Kozlyuk wrote: > > > Hello, > > > > Does MinGW-w64 builds support native thread-local storage (TLS), > > If by MinGW-w64 you mean GCC targeting MinGW-w64, then no. GCC only > supports emutls on MinGW-w