CC_NO_CLANG should be set according to the value of CC after overridden.
I have linked /usr/bin/cc to /usr/bin/clang and I built perf with a gcc
cross-compiler:
$ ARCH=arm64 CROSS_COMPILE=aarch64-calvin-linux-gnu- make -C \
../linux/tools/perf/ O=$(pwd)
It worked well. But when I tried to rebuild that with FIXDEP=1:
$ ARCH=arm64 CROSS_COMPILE=aarch64-calvin-linux-gnu- make -C \
../linux/tools/perf/ O=$(pwd) FIXDEP=1
Every .o files were rebuilt since EXTRA_WARNINGS was changed due to
false value of CC_NO_CLANG. Things worked in first build because submake
of Makefile.perf inherited CC from first make and CC_NO_CLANG was
rectified in submake.
Signed-off-by: Calvin Zhang <zhq2...@mail.ustc.edu.cn>
---
tools/scripts/Makefile.include | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/scripts/Makefile.include b/tools/scripts/Makefile.include
index a7974638561c..dc887669828b 100644
--- a/tools/scripts/Makefile.include
+++ b/tools/scripts/Makefile.include
@@ -39,8 +39,6 @@ EXTRA_WARNINGS += -Wundef
EXTRA_WARNINGS += -Wwrite-strings
EXTRA_WARNINGS += -Wformat
-CC_NO_CLANG := $(shell $(CC) -dM -E -x c /dev/null | grep -Fq "__clang__";
echo $$?)
-
# Makefiles suck: This macro sets a default value of $(2) for the
# variable named by $(1), unless the variable has been set by
# environment or command line. This is necessary for CC and AR
@@ -59,6 +57,8 @@ $(call allow-override,LD,$(CROSS_COMPILE)ld)
$(call allow-override,CXX,$(CROSS_COMPILE)g++)
$(call allow-override,STRIP,$(CROSS_COMPILE)strip)
+CC_NO_CLANG := $(shell $(CC) -dM -E -x c /dev/null | grep -Fq "__clang__";
echo $$?)
+
ifeq ($(CC_NO_CLANG), 1)
EXTRA_WARNINGS += -Wstrict-aliasing=3
endif
--
2.18.4
