diff options
| author | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-10-13 23:12:35 +0300 |
|---|---|---|
| committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2016-10-24 17:07:36 +0300 |
| commit | ef2c3e76d98dfb69a46d870b47656e8e5bac6e2b (patch) | |
| tree | 4d44c261089d351d18b44cc11542e7ce9b5a3473 /tools/perf/util/jitdump.c | |
| parent | ac12f6764c5097e791cd44f10b8943b40f44bfe7 (diff) | |
| download | linux-ef2c3e76d98dfb69a46d870b47656e8e5bac6e2b.tar.xz | |
perf jit: Avoid returning garbage for a ret variable
When the loop body isn't executed at all, then the 'ret' local variable,
that is uninitialized will be used as the return value.
This triggers this error on Alpine Linux:
CC /tmp/build/perf/util/demangle-java.o
CC /tmp/build/perf/util/demangle-rust.o
CC /tmp/build/perf/util/jitdump.o
CC /tmp/build/perf/util/genelf.o
util/jitdump.c: In function 'jit_process':
util/jitdump.c:622:3: error: 'ret' may be used uninitialized in this function [-Werror=maybe-uninitialized]
fprintf(stderr, "injected: %s (%d)\n", path, ret);
^
util/jitdump.c:584:6: note: 'ret' was declared here
int ret;
^
FLEX /tmp/build/perf/util/parse-events-flex.c
/ $ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-alpine-linux-musl/5.3.0/lto-wrapper
Target: x86_64-alpine-linux-musl
Configured with: /home/buildozer/aports/main/gcc/src/gcc-5.3.0/configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info
+--build=x86_64-alpine-linux-musl --host=x86_64-alpine-linux-musl --target=x86_64-alpine-linux-musl --with-pkgversion='Alpine 5.3.0' --enable-checking=release
+--disable-fixed-point --disable-libstdcxx-pch --disable-multilib --disable-nls --disable-werror --disable-symvers --enable-__cxa_atexit --enable-esp
+--enable-cloog-backend --enable-languages=c,c++,objc,java,fortran,ada --disable-libssp --disable-libmudflap --disable-libsanitizer --enable-shared
+--enable-threads --enable-tls --with-system-zlib
Thread model: posix
gcc version 5.3.0 (Alpine 5.3.0)
But this so far got under the radar, not causing any build problem, till the
"perf jit: enable jitdump support without dwarf" gets applied, when the above
problem takes place, some combination of inlining or whatever, the problem
is real, so fix it by initializing the variable to zero.
Cc: Anton Blanchard <anton@ozlabs.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Maciej Debski <maciejd@google.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lkml.kernel.org/r/20161013200437.GA12815@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/jitdump.c')
| -rw-r--r-- | tools/perf/util/jitdump.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/tools/perf/util/jitdump.c b/tools/perf/util/jitdump.c index 95f0884aae02..f3ed3c963c71 100644 --- a/tools/perf/util/jitdump.c +++ b/tools/perf/util/jitdump.c @@ -581,7 +581,7 @@ static int jit_process_dump(struct jit_buf_desc *jd) { union jr_entry *jr; - int ret; + int ret = 0; while ((jr = jit_get_next_entry(jd))) { switch(jr->prefix.id) { |