Makefile: Check $CC variable returned from xcompile is not empty.

If xcompile can't find out suitable GCC compiler for i386/armv7, it
will not set $CC_i386/$CC_armv7 variable. Makefile sets $CC variable
from xcompile, and will print strange error messages when executing
$CC program if $CC is empty.

Add checking to avoid this problem. If $CC is empty, also delete
invalid .xcompile file, so Make can recreate this file next time.

Change-Id: Ia8d481d76ca52f3351cb99f05779d06947161c5d
Signed-off-by: Andrew Wu <arw@dmp.com.tw>
Reviewed-on: http://review.coreboot.org/3905
Tested-by: build bot (Jenkins)
Reviewed-by: Jonathan A. Kollasch <jakllsch@kollasch.net>
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>

1 files changed, 5 insertions, 0 deletions

diff --git a/Makefile b/Makefile
index b709d14a9d..11222d65c5 100644
--- a/Makefile
+++ b/Makefile
@@ -138,6 +138,11 @@ AR := $(AR_$(ARCH-y))
 
 CFLAGS += $(CFLAGS_$(ARCH-y))
 
+ifeq ($(CC),)
+$(shell rm .xcompile)
+$(error no suitable GCC for $(ARCH-y))
+endif
+
 LIBGCC_FILE_NAME := $(shell test -r `$(CC) -print-libgcc-file-name` && \
 		      $(CC) -print-libgcc-file-name)