On Mon, 13 Feb 2017 14:20:20 -0300 Arnaldo Carvalho de Melo <[email protected]> wrote:
> Sure, now take a look at this another one: > > commit 6401e4361df183bd9953dce56f7c51d8ef28b11e > Author: Arnaldo Carvalho de Melo <[email protected]> > Date: Mon Feb 13 13:33:57 2017 -0300 > > tools lib traceevent plugin function: Initialize 'index' variable > > Detected with clang: > > CC /tmp/build/perf/plugin_function.o > plugin_function.c:145:6: warning: variable 'index' is used > uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] > if (parent && ftrace_indent->set) > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ > plugin_function.c:148:29: note: uninitialized use occurs here > trace_seq_printf(s, "%*s", index*3, ""); > ^~~~~ > plugin_function.c:145:2: note: remove the 'if' if its condition is > always true > if (parent && ftrace_indent->set) > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > plugin_function.c:145:6: warning: variable 'index' is used > uninitialized whenever '&&' condition is false [-Wsometimes-uninitialized] > if (parent && ftrace_indent->set) > ^~~~~~ > plugin_function.c:148:29: note: uninitialized use occurs here > trace_seq_printf(s, "%*s", index*3, ""); > ^~~~~ > plugin_function.c:145:6: note: remove the '&&' if its condition is > always true > if (parent && ftrace_indent->set) > ^~~~~~~~~ > plugin_function.c:133:11: note: initialize the variable 'index' to > silence this warning > int index; > ^ > = 0 > 2 warnings generated. I wonder why gcc isn't catching these. These look pretty obvious to me. > > Cc: Adrian Hunter <[email protected]> > Cc: David Ahern <[email protected]> > Cc: Jiri Olsa <[email protected]> > Cc: Namhyung Kim <[email protected]> > Cc: Wang Nan <[email protected]> > Link: http://lkml.kernel.org/n/[email protected] > Signed-off-by: Arnaldo Carvalho de Melo <[email protected]> > > diff --git a/tools/lib/traceevent/plugin_function.c > b/tools/lib/traceevent/plugin_function.c > index a00ec190821a..42dbf73758f3 100644 > --- a/tools/lib/traceevent/plugin_function.c > +++ b/tools/lib/traceevent/plugin_function.c > @@ -130,7 +130,7 @@ static int function_handler(struct trace_seq *s, struct > pevent_record *record, > unsigned long long pfunction; > const char *func; > const char *parent; > - int index; > + int index = 0; > > if (pevent_get_field_val(s, event, "ip", record, &function, 1)) > return trace_seq_putc(s, '!'); > Reviewed-by: Steven Rostedt (VMware) <[email protected]> -- Steve
