glew: use CC from environment

Also default LD is exported from outer make, override that.

Change-Id: Iefbe7fce93e9021cbd9bb087d9becace85138f07

external/glew/ExternalProject_glew.mk

@@ -24,7 +24,8 @@ else
 
 $(call gb_ExternalProject_get_state_target,glew,build) :
 	$(call gb_ExternalProject_run,glew,\
-		$(if $(filter TRUE,$(ENABLE_DEBUG)),STRIP=) $(MAKE) glew.lib $(if $(filter TRUE,$(ENABLE_DEBUG)),debug) \
+		$(if $(filter TRUE,$(ENABLE_DEBUG)),STRIP=) LD=$(CC) \
+			$(MAKE) glew.lib $(if $(filter TRUE,$(ENABLE_DEBUG)),debug) \
 	)
 
 endif

external/glew/UnpackedTarball_glew.mk

@@ -18,6 +18,11 @@ $(eval $(call gb_UnpackedTarball_set_patchflags,glew,--binary))
 $(eval $(call gb_UnpackedTarball_add_patches,glew,\
 	external/glew/glew-fix-rc-error.patch.1 \
 ))
+else
+$(eval $(call gb_UnpackedTarball_add_patches,glew,\
+	external/glew/glew_use_CC_variable.patch.1 \
+))
 endif
 
+
 # vim: set noet sw=4 ts=4:

external/glew/glew_use_CC_variable.patch.1

+Use CC variable from environment, don't hardcode "cc".
+
+--- glew/config/Makefile.linux.orig	2014-01-29 15:39:43.364972925 +0100
++++ glew/config/Makefile.linux	2014-01-29 15:44:45.621000941 +0100
+@@ -1,6 +1,6 @@
+ NAME = $(GLEW_NAME)
+-CC = cc
+-LD = cc
++CC ?= cc
++LD ?= $(CC)
+ M_ARCH ?= $(shell uname -m)
+ ARCH64 = false
+ ifeq (x86_64,${M_ARCH})
+--- glew/config/Makefile.darwin.orig	2014-01-29 15:44:39.541000377 +0100
++++ glew/config/Makefile.darwin	2014-01-29 15:44:47.548001120 +0100
+@@ -1,6 +1,6 @@
+ NAME = $(GLEW_NAME)
+-CC = cc
+-LD = cc
++CC ?= cc
++LD ?= $(CC)
+ CFLAGS.EXTRA = -dynamic -fno-common
+ #CFLAGS.EXTRA += -no-cpp-precomp
+ LDFLAGS.EXTRA =