linux/arch/um/Makefile-i386
Jeff Dike 4f81c5350b [UML] fix gcc ICEs and unresolved externs
There are various constraints on the use of unit-at-a-time:
 - i386 uses no-unit-at-a-time for pre-4.0 (not 4.3)
 - x86_64 uses unit-at-a-time always

Uli reported a crash on x86_64 with gcc 4.1.2 with unit-at-a-time,
resulting in commit c0a18111e5

Ingo reported a gcc internal error with gcc 4.3 with no-unit-at-a-timem,
resulting in 22eecde2f9

Benny Halevy is seeing extern inlines not resolved with gcc 4.3 with
no-unit-at-a-time

This patch reintroduces unit-at-a-time for gcc >= 4.0, bringing back the
possibility of Uli's crash.  If that happens, we'll debug it.

I started seeing both the internal compiler errors and unresolved
inlines on Fedora 9.  This patch fixes both problems, without so far
reintroducing the crash reported by Uli.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Cc: Benny Halevy <bhalevy@panasas.com>
Cc: Adrian Bunk <bunk@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-07 10:53:10 -07:00

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1.4 KiB
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core-y += arch/um/sys-i386/ arch/x86/crypto/
TOP_ADDR := $(CONFIG_TOP_ADDR)
START := 0x8048000
LDFLAGS += -m elf_i386
ELF_ARCH := $(SUBARCH)
ELF_FORMAT := elf32-$(SUBARCH)
OBJCOPYFLAGS := -O binary -R .note -R .comment -S
HEADER_ARCH := x86
CHECKFLAGS += -D__i386__
ifeq ("$(origin SUBARCH)", "command line")
ifneq ("$(shell uname -m | sed -e s/i.86/i386/)", "$(SUBARCH)")
KBUILD_CFLAGS += $(call cc-option,-m32)
KBUILD_AFLAGS += $(call cc-option,-m32)
LINK-y += $(call cc-option,-m32)
UML_OBJCOPYFLAGS += -F $(ELF_FORMAT)
export LDFLAGS HOSTCFLAGS HOSTLDFLAGS UML_OBJCOPYFLAGS
endif
endif
# First of all, tune CFLAGS for the specific CPU. This actually sets cflags-y.
include $(srctree)/arch/x86/Makefile_32.cpu
# prevent gcc from keeping the stack 16 byte aligned. Taken from i386.
cflags-y += $(call cc-option,-mpreferred-stack-boundary=2)
# Prevent sprintf in nfsd from being converted to strcpy and resulting in
# an unresolved reference.
cflags-y += -ffreestanding
# Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use
# a lot more stack due to the lack of sharing of stacklots. Also, gcc
# 4.3.0 needs -funit-at-a-time for extern inline functions.
KBUILD_CFLAGS += $(shell if [ $(call cc-version) -lt 0400 ] ; then \
echo $(call cc-option,-fno-unit-at-a-time); \
else echo $(call cc-option,-funit-at-a-time); fi ;)
KBUILD_CFLAGS += $(cflags-y)