kbuild: remove GCC_VERSION

This was causing some ordering problems.  Remove the up-front evaluation
and just revaluate the compiler version each time we need it.

(The up-front evaluation was problematic because some architectures modify
the value of $(CC)).

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index a13eb57..b98f11b 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -76,8 +76,7 @@
 CHECKFLAGS	+= -m$(SZ) -D__powerpc__ -D__powerpc$(SZ)__
 
 ifeq ($(CONFIG_PPC64),y)
-GCC_VERSION     := $(call cc-version)
-GCC_BROKEN_VEC	:= $(shell if [ $(GCC_VERSION) -lt 0400 ] ; then echo "y"; fi)
+GCC_BROKEN_VEC	:= $(shell if [ $(call cc-version) -lt 0400 ] ; then echo "y"; fi)
 
 ifeq ($(CONFIG_POWER4_ONLY),y)
 ifeq ($(CONFIG_ALTIVEC),y)
@@ -189,10 +188,9 @@
 # Ensure this is binutils 2.12.1 (or 2.12.90.0.7) or later for altivec
 # instructions.
 # gcc-3.4 and binutils-2.14 are a fatal combination.
-GCC_VERSION	:= $(call cc-version)
 
 checkbin:
-	@if test "$(GCC_VERSION)" = "0304" ; then \
+	@if test "$(call cc-version)" = "0304" ; then \
 		if ! /bin/echo mftb 5 | $(AS) -v -mppc -many -o $(TOUT) >/dev/null 2>&1 ; then \
 			echo -n '*** ${VERSION}.${PATCHLEVEL} kernels no longer build '; \
 			echo 'correctly with gcc-3.4 and your version of binutils.'; \