[PATCH 13/27] perf tools: Let python use correct gcc for build_ext

From: Arnaldo Carvalho de Melo
Date: Thu Jun 23 2016 - 17:25:30 EST


From: He Kuang <hekuang@xxxxxxxxxx>

Currently, python uses host gcc instead of cross-compile gcc in the last
step of compiling build_ext(remove '--quiet' to show verbose):

cross-gcc ...
cross-gcc ...
creating ~/out/python_ext_build/lib
gcc -pthread -shared -Wl,-z ...

This is wrong but may not cause any errors unless the features detected
by cross-compiler do not match those for host compiler, and causes the
following errors:

/usr/lib64/gcc/bin/ld: cannot find -lunwind-x86
collect2: error: ld returned 1 exit status
error: command 'gcc' failed with exit status 1
cp: cannot stat â~/out/python_ext_build/lib/perf.soâ: No such file or directory
Makefile.perf:257: recipe for target '~/out/python/perf.so' failed
make[1]: *** [~/out/python/perf.so] Error 1
Makefile:68: recipe for target 'all' failed
make: *** [all] Error 2

This issue is also reported and anwsered on stackoverflow.
Link: http://stackoverflow.com/questions/5986256/python-distutils-gcc-path

Signed-off-by: He Kuang <hekuang@xxxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: David Ahern <dsahern@xxxxxxxxx>
Cc: Ekaterina Tumanova <tumanova@xxxxxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxx>
Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Pekka Enberg <penberg@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxxxxxxx>
Cc: Wang Nan <wangnan0@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1466578626-92406-5-git-send-email-hekuang@xxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/Makefile.perf | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index bde8cbae7dd9..d0a2cb11296f 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -254,7 +254,8 @@ PYTHON_EXT_SRCS := $(shell grep -v ^\# util/python-ext-sources)
PYTHON_EXT_DEPS := util/python-ext-sources util/setup.py $(LIBTRACEEVENT) $(LIBAPI)

$(OUTPUT)python/perf.so: $(PYTHON_EXT_SRCS) $(PYTHON_EXT_DEPS) $(LIBTRACEEVENT_DYNAMIC_LIST)
- $(QUIET_GEN)CFLAGS='$(CFLAGS)' LDFLAGS='$(LDFLAGS) $(LIBTRACEEVENT_DYNAMIC_LIST_LDFLAGS)' \
+ $(QUIET_GEN)LDSHARED="$(CC) -pthread -shared" \
+ CFLAGS='$(CFLAGS)' LDFLAGS='$(LDFLAGS) $(LIBTRACEEVENT_DYNAMIC_LIST_LDFLAGS)' \
$(PYTHON_WORD) util/setup.py \
--quiet build_ext; \
mkdir -p $(OUTPUT)python && \
--
2.5.5