[syslinux] [PATCH 18/19] mk: Don't link against compiler's version of libgcc

[H. Peter Anvin]

How do they differ?  It seems like one or the other must be buggy...

Matt Fleming <matt at console-pimps.org> wrote:

>From: Matt Fleming <matt.fleming at intel.com>
>
>Syslinux provides its own copy of libgcc functions in
>com32/lib/libgcc, so we don't need to link against the version
>provided by the compiler. What's worse, the behaviour is different
>between the two versions.
>
>This caused problems, for example, when parsing the TOTALTIMEOUT
>config directive in com32/menu because of the following calculation,
>
>	totaltimeout = (atoll(skipspace(p + 13)) * CLK_TCK + 9) / 10;
>
>which invokes __divdi3() as provided by libgcc. The results returned
>by the Syslinux and compiler's copy of libgcc differ, leading to
>differences in behaviour.
>
>Signed-off-by: Matt Fleming <matt.fleming at intel.com>
>---
> mk/elf.mk |    3 +--
> 1 files changed, 1 insertions(+), 2 deletions(-)
>
>diff --git a/mk/elf.mk b/mk/elf.mk
>index 5a2ce2d..ca06115 100644
>--- a/mk/elf.mk
>+++ b/mk/elf.mk
>@@ -47,14 +47,13 @@ CFLAGS     = $(GCCOPT) -W -Wall -march=i386 \
> 	     -I$(com32)/libutil/include -I$(com32)/include $(GPLINCLUDE)
> SFLAGS     = $(GCCOPT) -D__COM32__ -march=i386
>LDFLAGS    = -m elf_i386 -shared --hash-style=gnu -T
>$(com32)/lib/elf32.ld
>-LIBGCC    := $(shell $(CC) $(GCCOPT) --print-libgcc)
> 
> LNXCFLAGS  = -I$(com32)/libutil/include -W -Wall -O -g -D_GNU_SOURCE
> LNXSFLAGS  = -g
> LNXLDFLAGS = -g
> 
> C_LIBS	   = $(com32)/libutil/libutil_com.c32 $(GPLLIB) \
>-	     $(com32)/lib/libcom32.c32 $(LIBGCC)
>+	     $(com32)/lib/libcom32.c32
> C_LNXLIBS  = $(com32)/libutil/libutil_lnx.a \
> 	     $(com32)/elflink/ldlinux/ldlinux_lnx.a
> 
>-- 
>1.7.4.4

-- 
Sent from my mobile phone. Please excuse my brevity and lack of formatting.