diff options
Diffstat (limited to 'contrib/guix/patches/gcc-broken-longjmp.patch')
| -rw-r--r-- | contrib/guix/patches/gcc-broken-longjmp.patch | 70 |
1 files changed, 0 insertions, 70 deletions
diff --git a/contrib/guix/patches/gcc-broken-longjmp.patch b/contrib/guix/patches/gcc-broken-longjmp.patch deleted file mode 100644 index 56568813c0..0000000000 --- a/contrib/guix/patches/gcc-broken-longjmp.patch +++ /dev/null @@ -1,70 +0,0 @@ -commit eb5698897c52702498938592d7f76e67d126451f -Author: Eric Botcazou <ebotcazou@adacore.com> -Date: Wed May 5 22:48:51 2021 +0200 - - Fix PR target/100402 - - This is a regression for 64-bit Windows present from mainline down to the 9 - branch and introduced by the fix for PR target/99234. Again SEH, but with - a twist related to the way MinGW implements setjmp/longjmp, which turns out - to be piggybacked on SEH with recent versions of MinGW, i.e. the longjmp - performs a bona-fide unwinding of the stack, because it calls RtlUnwindEx - with the second argument initially passed to setjmp, which is the result of - __builtin_frame_address (0) in the MinGW header file: - - define setjmp(BUF) _setjmp((BUF), __builtin_frame_address (0)) - - This means that we directly expose the frame pointer to the SEH machinery - here (unlike with regular exception handling where we use an intermediate - CFA) and thus that we cannot do whatever we want with it. The old code - would leave it unaligned, i.e. not multiple of 16, whereas the new code - aligns it, but this breaks for some reason; at least it appears that a - .seh_setframe directive with 0 as second argument always works, so the - fix aligns it this way. - - gcc/ - PR target/100402 - * config/i386/i386.c (ix86_compute_frame_layout): For a SEH target, - always return the establisher frame for __builtin_frame_address (0). - gcc/testsuite/ - * gcc.c-torture/execute/20210505-1.c: New test. - - This patch can be dropped when we are building with GCC 10.4.0 or later. - -diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c -index 2f838840e96..06ad1b2274e 100644 ---- a/gcc/config/i386/i386.c -+++ b/gcc/config/i386/i386.c -@@ -6356,12 +6356,29 @@ ix86_compute_frame_layout (void) - area, see the SEH code in config/i386/winnt.c for the rationale. */ - frame->hard_frame_pointer_offset = frame->sse_reg_save_offset; - -- /* If we can leave the frame pointer where it is, do so. Also, return -+ /* If we can leave the frame pointer where it is, do so; however return - the establisher frame for __builtin_frame_address (0) or else if the -- frame overflows the SEH maximum frame size. */ -+ frame overflows the SEH maximum frame size. -+ -+ Note that the value returned by __builtin_frame_address (0) is quite -+ constrained, because setjmp is piggybacked on the SEH machinery with -+ recent versions of MinGW: -+ -+ # elif defined(__SEH__) -+ # if defined(__aarch64__) || defined(_ARM64_) -+ # define setjmp(BUF) _setjmp((BUF), __builtin_sponentry()) -+ # elif (__MINGW_GCC_VERSION < 40702) -+ # define setjmp(BUF) _setjmp((BUF), mingw_getsp()) -+ # else -+ # define setjmp(BUF) _setjmp((BUF), __builtin_frame_address (0)) -+ # endif -+ -+ and the second argument passed to _setjmp, if not null, is forwarded -+ to the TargetFrame parameter of RtlUnwindEx by longjmp (after it has -+ built an ExceptionRecord on the fly describing the setjmp buffer). */ - const HOST_WIDE_INT diff - = frame->stack_pointer_offset - frame->hard_frame_pointer_offset; -- if (diff <= 255) -+ if (diff <= 255 && !crtl->accesses_prior_frames) - { - /* The resulting diff will be a multiple of 16 lower than 255, - i.e. at most 240 as required by the unwind data structure. */ |