Commit a137802ee839ace40079bebde24cfb416f73208a
1 parent
8b9f2caa02
Don't use '-fwrapv' compiler option: it's buggy in gcc-4.1.x
This causes kernel images that don't run init to completion with certain broken gcc versions. This fixes kernel bugzilla entry: http://bugzilla.kernel.org/show_bug.cgi?id=13012 I suspect the gcc problem is this: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28230 Fix the problem by using the -fno-strict-overflow flag instead, which not only does not exist in the known-to-be-broken versions of gcc (it was introduced later than fwrapv), but seems to be much less disturbing to gcc too: the difference in the generated code by -fno-strict-overflow are smaller (compared to using neither flag) than when using -fwrapv. Reported-by: Barry K. Nathan <barryn@pobox.com> Pushed-by: Frans Pop <elendil@planet.nl> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Showing 1 changed file with 1 additions and 1 deletions Side-by-side Diff
Makefile
... | ... | @@ -565,7 +565,7 @@ |
565 | 565 | KBUILD_CFLAGS += $(call cc-option,-Wno-pointer-sign,) |
566 | 566 | |
567 | 567 | # disable invalid "can't wrap" optimizations for signed / pointers |
568 | -KBUILD_CFLAGS += $(call cc-option,-fwrapv) | |
568 | +KBUILD_CFLAGS += $(call cc-option,-fno-strict-overflow) | |
569 | 569 | |
570 | 570 | # revert to pre-gcc-4.4 behaviour of .eh_frame |
571 | 571 | KBUILD_CFLAGS += $(call cc-option,-fno-dwarf2-cfi-asm) |