don't specify "CC=<nothing>" on kernel build command line

If KERNEL_CC isn't set, we end up with a "CC=" on the kernel build
command-line. We don't always need CC, as the CROSS_COMPILE flag does
the job instead. In fact, specifying CC messes up the build when we're
using a biarch compiler.

This change doesn't specify CC= if the KERNEL_CC variable is empty.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@9408 3c298f89-4303-0410-b956-a3cf2f4a3e73

diff --git a/include/kernel-defaults.mk b/include/kernel-defaults.mk
index fd5bb1c..9779921 100644 (file)
--- a/include/kernel-defaults.mk
+++ b/include/kernel-defaults.mk
@@ -40,6 +40,10 @@ KERNEL_MAKEOPTS := -C $(LINUX_DIR) \
        ARCH="$(LINUX_KARCH)" \
        CONFIG_SHELL="$(BASH)"
 
+ifneq (,$(KERNEL_CC))
+  KERNEL_MAKEOPTS += CC="$(KERNEL_CC)"
+endif
+
 # defined in quilt.mk
 Kernel/Patch:=$(Kernel/Patch/Default)
 define Kernel/Prepare/Default
@@ -50,11 +54,11 @@ endef
 
 define Kernel/Configure/2.4
        $(SED) "s,\-mcpu=,\-mtune=,g;" $(LINUX_DIR)/arch/mips/Makefile
-       $(MAKE) $(KERNEL_MAKEOPTS) CC="$(KERNEL_CC)" oldconfig include/linux/compile.h include/linux/version.h
+       $(MAKE) $(KERNEL_MAKEOPTS) oldconfig include/linux/compile.h include/linux/version.h
        $(MAKE) $(KERNEL_MAKEOPTS) dep
 endef
 define Kernel/Configure/2.6
-       -$(MAKE) $(KERNEL_MAKEOPTS) CC="$(KERNEL_CC)" oldconfig prepare scripts
+       -$(MAKE) $(KERNEL_MAKEOPTS) oldconfig prepare scripts
 endef
 define Kernel/Configure/Default
        $(LINUX_CONFCMD) > $(LINUX_DIR)/.config.target
@@ -66,7 +70,7 @@ endef
 
 define Kernel/CompileModules/Default
        rm -f $(LINUX_DIR)/vmlinux $(LINUX_DIR)/System.map
-       $(MAKE) $(KERNEL_MAKEOPTS) CC="$(KERNEL_CC)" modules
+       $(MAKE) $(KERNEL_MAKEOPTS) modules
 endef
 
 ifeq ($(KERNEL),2.6)
@@ -89,7 +93,7 @@ ifeq ($(KERNEL),2.6)
 endif
 define Kernel/CompileImage/Default
        $(call Kernel/SetInitramfs)
-       $(MAKE) $(KERNEL_MAKEOPTS) CC="$(KERNEL_CC)" $(KERNELNAME)
+       $(MAKE) $(KERNEL_MAKEOPTS) $(KERNELNAME)
        $(KERNEL_CROSS)objcopy -O binary -R .reginfo -R .note -R .comment -R .mdebug -S $(LINUX_DIR)/vmlinux $(LINUX_KERNEL)
        $(KERNEL_CROSS)objcopy -R .reginfo -R .note -R .comment -R .mdebug -S $(LINUX_DIR)/vmlinux $(KERNEL_BUILD_DIR)/vmlinux.elf
 endef

diff --git a/include/kernel.mk b/include/kernel.mk
index f9baeef..4bdd24a 100644 (file)
--- a/include/kernel.mk
+++ b/include/kernel.mk
@@ -23,11 +23,11 @@ else
   endif
 
   ifneq (,$(findstring uml,$(BOARD)))
-    KERNEL_CC:=$(HOSTCC)
-    KERNEL_CROSS:=
+    KERNEL_CC?=$(HOSTCC)
+    KERNEL_CROSS?=
   else
-    KERNEL_CC:=$(TARGET_CC)
-    KERNEL_CROSS:=$(TARGET_CROSS)
+    KERNEL_CC?=$(TARGET_CC)
+    KERNEL_CROSS?=$(TARGET_CROSS)
   endif
 
   PATCH_DIR ?= ./patches$(shell [ -d "./patches-$(KERNEL_PATCHVER)" ] && printf -- "-$(KERNEL_PATCHVER)" || true )