Add -Wno-unused-command-line-argument to clang cflags to enable ccache.
Previously ccache is disabled when it fails calling clang's preprocessor with
unused arguments (such as '-Wa,--noexecstack') in the command line.
See http://petereisentraut.blogspot.com/2011/05/ccache-and-clang.html.
(-Qunused-arguments suppresses more than
-Wno-unused-command-line-argument does.)
Change-Id: I6cde307632c8395c053eb28063d7844d93070562
diff --git a/core/clang/config.mk b/core/clang/config.mk
index bdd18d8..9ae2693 100644
--- a/core/clang/config.mk
+++ b/core/clang/config.mk
@@ -42,6 +42,11 @@
CLANG_CONFIG_EXTRA_CFLAGS += \
-Werror=int-conversion
+# Workaround for ccache with clang.
+# See http://petereisentraut.blogspot.com/2011/05/ccache-and-clang.html.
+CLANG_CONFIG_EXTRA_CFLAGS += \
+ -Wno-unused-command-line-argument
+
CLANG_CONFIG_UNKNOWN_CFLAGS := \
-finline-limit=64 \
-fno-canonical-system-headers \