[tip: perf/urgent] perf python: Fix clang detection to strip out options passed in $CC

tip-bot2 for Arnaldo Carvalho de Melo
2020-04-04T08:41:52Z

The following commit has been merged into the perf/urgent branch of tip:

Commit-ID: 9ff76cea4e9e6d49a6f764ae114fc0fb8de97816
Gitweb: https://git.kernel.org/tip/9ff76cea4e9e6d49a6f764ae114fc0fb8de97816
Author: Arnaldo Carvalho de Melo <acme@redhat.com>
AuthorDate: Wed, 01 Apr 2020 09:33:59 -03:00
Committer: Arnaldo Carvalho de Melo <acme@redhat.com>
CommitterDate: Fri, 03 Apr 2020 10:04:59 -03:00

perf python: Fix clang detection to strip out options passed in $CC

The clang check in the python setup.py file expected $CC to be just the
name of the compiler, not the compiler + options, i.e. all options were
expected to be passed in $CFLAGS, this ends up making it fail in systems
where CC is set to, e.g.:

"aarch64-linaro-linux-gcc --sysroot=/oe/build/tmp/work/juno-linaro-linux/perf/1.0-r9/recipe-sysroot"

Like this:

$ python3
>>> from subprocess import Popen
>>> a = Popen(["aarch64-linux-gnu-gcc --sysroot=/oe/build/tmp/work/juno-linaro-linux/perf/1.0-r9/recipe-sysroot", "-v"])
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/python3.6/subprocess.py", line 729, in __init__
restore_signals, start_new_session)
File "/usr/lib/python3.6/subprocess.py", line 1364, in _execute_child
raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'aarch64-linux-gnu-gcc --sysroot=/oe/build/tmp/work/juno-linaro-linux/perf/1.0-r9/recipe-sysroot': 'aarch64-linux-gnu-gcc --sysroot=/oe/build/tmp/work/juno-linaro-linux/perf/1.0-r9/recipe-sysroot'
>>>

Make it more robust, covering this case, by passing cc.split()[0] as the
first arg to popen().

Fixes: a7ffd416d804 ("perf python: Fix clang detection when using CC=clang-version")
Reported-by: Daniel Díaz <daniel.diaz@linaro.org>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Tested-by: Daniel Díaz <daniel.diaz@linaro.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ilie Halip <ilie.halip@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20200401124037.GA12534@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/util/setup.py | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/perf/util/setup.py b/tools/perf/util/setup.py
index 8a065a6..347b2c0 100644
--- a/tools/perf/util/setup.py
+++ b/tools/perf/util/setup.py
@@ -3,7 +3,7 @@ from subprocess import Popen, PIPE
from re import sub

cc = getenv("CC")
-cc_is_clang = b"clang version" in Popen([cc, "-v"], stderr=PIPE).stderr.readline()
+cc_is_clang = b"clang version" in Popen([cc.split()[0], "-v"], stderr=PIPE).stderr.readline()

def clang_has_option(option):
return [o for o in Popen([cc, option], stderr=PIPE).stderr.readlines() if b"unknown argument" in o] == [ ]