path: root/scripts/Kbuild.include
diff options
authorJan Beulich <jbeulich@novell.com>2006-09-26 10:52:41 +0200
committerAndi Kleen <andi@basil.nowhere.org>2006-09-26 10:52:41 +0200
commitadf1423698f00d00b267f7dca8231340ce7d65ef (patch)
treeec2e28a32d467cc3c618c8ee0cedd3d1a49f9c43 /scripts/Kbuild.include
parentab2e0b46cb9a197fab7d98e147cac7cd41a14047 (diff)
[PATCH] i386/x86-64: Work around gcc bug with noreturn functions in unwinder
Current gcc generates calls not jumps to noreturn functions. When that happens the return address can point to the next function, which confuses the unwinder. This patch works around it by marking asynchronous exception frames in contrast normal call frames in the unwind information. Then teach the unwinder to decode this. For normal call frames the unwinder now subtracts one from the address which avoids this problem. The standard libgcc unwinder uses the same trick. It doesn't include adjustment of the printed address (i.e. for the original example, it'd still be kernel_math_error+0 that gets displayed, but the unwinder wouldn't get confused anymore. This only works with binutils 2.6.17+ and some versions of H.J.Lu's 2.6.16 unfortunately because earlier binutils don't support .cfi_signal_frame [AK: added automatic detection of the new binutils and wrote description] Signed-off-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Andi Kleen <ak@suse.de>
Diffstat (limited to 'scripts/Kbuild.include')
1 files changed, 2 insertions, 2 deletions
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 7adef12a0c2..4f5ff19b992 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -66,8 +66,8 @@ as-option = $(shell if $(CC) $(CFLAGS) $(1) -Wa,-Z -c -o /dev/null \
# as-instr
# Usage: cflags-y += $(call as-instr, instr, option1, option2)
-as-instr = $(shell if echo -e "$(1)" | $(AS) -Z -o astest$$$$.out \
- 2>&1 >/dev/null ; then echo "$(2)"; else echo "$(3)"; fi; \
+as-instr = $(shell if echo -e "$(1)" | $(AS) >/dev/null 2>&1 -W -Z -o astest$$$$.out ; \
+ then echo "$(2)"; else echo "$(3)"; fi; \
rm -f astest$$$$.out)
# cc-option