[PATCH] kbuild: Fix gcc -x syntax

From: Jean Delvare
Date: Fri Sep 28 2012 - 15:13:09 EST


The correct syntax for gcc -x is "gcc -x assembler", not
"gcc -xassembler". Even though the latter happens to work, the former
is what is documented in the manual page and thus what gcc wrappers
such as icecream do expect.

This isn't a cosmetic change. The missing space prevents icecream from
recognizing compilation tasks it can't handle, leading to silent kernel
miscompilations.

Besides me, credits go to Richard Guenther and Dirk Mueller for
investigating the miscompilation issue and tracking it down to this
incorrect -x parameter syntax.

Signed-off-by: Jean Delvare <jdelvare@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Cc: Bernhard Walle <bernhard@xxxxxxxxx>
Cc: Michal Marek <mmarek@xxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
---
arch/mips/Makefile | 2 +-
arch/mips/kernel/Makefile | 2 +-
arch/x86/Makefile | 2 +-
scripts/Kbuild.include | 12 ++++++------
tools/power/cpupower/Makefile | 2 +-
5 files changed, 10 insertions(+), 10 deletions(-)

--- linux-3.6-rc7.orig/arch/mips/Makefile 2012-07-21 22:58:29.000000000 +0200
+++ linux-3.6-rc7/arch/mips/Makefile 2012-09-28 20:26:57.426173426 +0200
@@ -225,7 +225,7 @@ KBUILD_CPPFLAGS += -DDATAOFFSET=$(if $(d
LDFLAGS += -m $(ld-emul)

ifdef CONFIG_MIPS
-CHECKFLAGS += $(shell $(CC) $(KBUILD_CFLAGS) -dM -E -xc /dev/null | \
+CHECKFLAGS += $(shell $(CC) $(KBUILD_CFLAGS) -dM -E -x c /dev/null | \
egrep -vw '__GNUC_(|MINOR_|PATCHLEVEL_)_' | \
sed -e "s/^\#define /-D'/" -e "s/ /'='/" -e "s/$$/'/")
ifdef CONFIG_64BIT
--- linux-3.6-rc7.orig/arch/mips/kernel/Makefile 2012-07-21 22:58:29.000000000 +0200
+++ linux-3.6-rc7/arch/mips/kernel/Makefile 2012-09-28 20:27:02.099174587 +0200
@@ -104,7 +104,7 @@ obj-$(CONFIG_MIPS_MACHINE) += mips_machi

obj-$(CONFIG_OF) += prom.o

-CFLAGS_cpu-bugs64.o = $(shell if $(CC) $(KBUILD_CFLAGS) -Wa,-mdaddi -c -o /dev/null -xc /dev/null >/dev/null 2>&1; then echo "-DHAVE_AS_SET_DADDI"; fi)
+CFLAGS_cpu-bugs64.o = $(shell if $(CC) $(KBUILD_CFLAGS) -Wa,-mdaddi -c -o /dev/null -x c /dev/null >/dev/null 2>&1; then echo "-DHAVE_AS_SET_DADDI"; fi)

obj-$(CONFIG_HAVE_STD_PC_SERIAL_PORT) += 8250-platform.o

--- linux-3.6-rc7.orig/arch/x86/Makefile 2012-09-24 09:31:59.000000000 +0200
+++ linux-3.6-rc7/arch/x86/Makefile 2012-09-28 20:26:52.039172190 +0200
@@ -92,7 +92,7 @@ endif
ifdef CONFIG_X86_X32
x32_ld_ok := $(call try-run,\
/bin/echo -e '1: .quad 1b' | \
- $(CC) $(KBUILD_AFLAGS) -c -xassembler -o "$$TMP" - && \
+ $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" - && \
$(OBJCOPY) -O elf32-x86-64 "$$TMP" "$$TMPO" && \
$(LD) -m elf32_x86_64 "$$TMPO" -o "$$TMP",y,n)
ifeq ($(x32_ld_ok),y)
--- linux-3.6-rc7.orig/scripts/Kbuild.include 2012-07-21 22:58:29.000000000 +0200
+++ linux-3.6-rc7/scripts/Kbuild.include 2012-09-28 20:27:25.556178734 +0200
@@ -98,24 +98,24 @@ try-run = $(shell set -e; \
# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)

as-option = $(call try-run,\
- $(CC) $(KBUILD_CFLAGS) $(1) -c -xassembler /dev/null -o "$$TMP",$(1),$(2))
+ $(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))

# as-instr
# Usage: cflags-y += $(call as-instr,instr,option1,option2)

as-instr = $(call try-run,\
- printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -xassembler -o "$$TMP" -,$(2),$(3))
+ printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))

# cc-option
# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)

cc-option = $(call try-run,\
- $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -xc /dev/null -o "$$TMP",$(1),$(2))
+ $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))

# cc-option-yn
# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
cc-option-yn = $(call try-run,\
- $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -xc /dev/null -o "$$TMP",y,n)
+ $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)

# cc-option-align
# Prefix align with either -falign or -malign
@@ -125,7 +125,7 @@ cc-option-align = $(subst -functions=0,,
# cc-disable-warning
# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
cc-disable-warning = $(call try-run,\
- $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -xc /dev/null -o "$$TMP",-Wno-$(strip $(1)))
+ $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))

# cc-version
# Usage gcc-ver := $(call cc-version)
@@ -143,7 +143,7 @@ cc-ifversion = $(shell [ $(call cc-versi
# cc-ldoption
# Usage: ldflags += $(call cc-ldoption, -Wl$(comma)--hash-style=both)
cc-ldoption = $(call try-run,\
- $(CC) $(1) -nostdlib -xc /dev/null -o "$$TMP",$(1),$(2))
+ $(CC) $(1) -nostdlib -x c /dev/null -o "$$TMP",$(1),$(2))

# ld-option
# Usage: LDFLAGS += $(call ld-option, -X)
--- linux-3.6-rc7.orig/tools/power/cpupower/Makefile 2012-07-21 22:58:29.000000000 +0200
+++ linux-3.6-rc7/tools/power/cpupower/Makefile 2012-09-28 20:26:45.218170854 +0200
@@ -111,7 +111,7 @@ GMO_FILES = ${shell for HLANG in ${LANGU
export CROSS CC AR STRIP RANLIB CFLAGS LDFLAGS LIB_OBJS

# check if compiler option is supported
-cc-supports = ${shell if $(CC) ${1} -S -o /dev/null -xc /dev/null > /dev/null 2>&1; then echo "$(1)"; fi;}
+cc-supports = ${shell if $(CC) ${1} -S -o /dev/null -x c /dev/null > /dev/null 2>&1; then echo "$(1)"; fi;}

# use '-Os' optimization if available, else use -O2
OPTIMIZATION := $(call cc-supports,-Os,-O2)

--
Jean Delvare
Suse L3

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