[Qemu-trivial] [PATCH] Makefile: pass include directives to dtc via CPPFLAGS, not CFLAGS

[Peter Maydell]

The dtc submodule's makefile expects -I include directives to be
in CPPFLAGS, not CFLAGS. Getting this wrong meant that the include
directive would not be applied when generating the dependency .d
files. This in turn meant that we couldn't build libfdt when
doing an out of tree build with clang. (gcc's dependency output
is slightly different from clang in this situation so it happened
to work.)

Signed-off-by: Peter Maydell <address@hidden>
---
Tracking this down was not made any easier by make bug
http://savannah.gnu.org/bugs/index.php?15110 which meant that
make silently exited without saying anything about what was wrong...

 Makefile |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Makefile b/Makefile
index 3cfa7d0..c06bfab 100644
--- a/Makefile
+++ b/Makefile
@@ -146,10 +146,11 @@ $(SRC_PATH)/pixman/configure:
        (cd $(SRC_PATH)/pixman; autoreconf -v --install)
 
 DTC_MAKE_ARGS=-I$(SRC_PATH)/dtc VPATH=$(SRC_PATH)/dtc -C dtc V="$(V)" 
LIBFDT_srcdir=$(SRC_PATH)/dtc/libfdt
-DTC_CFLAGS=$(CFLAGS) $(QEMU_CFLAGS) -I$(BUILD_DIR)/dtc -I$(SRC_PATH)/dtc 
-I$(SRC_PATH)/dtc/libfdt
+DTC_CFLAGS=$(CFLAGS) $(QEMU_CFLAGS)
+DTC_CPPFLAGS=-I$(BUILD_DIR)/dtc -I$(SRC_PATH)/dtc -I$(SRC_PATH)/dtc/libfdt
 
 subdir-dtc:dtc/libfdt dtc/tests
-       $(call quiet-command,$(MAKE) $(DTC_MAKE_ARGS) CFLAGS="$(DTC_CFLAGS)" 
LDFLAGS="$(LDFLAGS)" ARFLAGS="$(ARFLAGS)" CC="$(CC)" AR="$(AR)" LD="$(LD)" 
$(SUBDIR_MAKEFLAGS) libfdt/libfdt.a,)
+       $(call quiet-command,$(MAKE) $(DTC_MAKE_ARGS) 
CPPFLAGS="$(DTC_CPPFLAGS)" CFLAGS="$(DTC_CFLAGS)" LDFLAGS="$(LDFLAGS)" 
ARFLAGS="$(ARFLAGS)" CC="$(CC)" AR="$(AR)" LD="$(LD)" $(SUBDIR_MAKEFLAGS) 
libfdt/libfdt.a,)
 
 dtc/%:
        mkdir -p $@
-- 
1.7.9.5