Re: [PATCH] trace-cmd: Silence a logical-not-parentheses warning

[Steven Rostedt <rostedt@goodmis.org>]

On Tue, 27 Apr 2021 22:25:40 -0700
Ian Rogers <irogers@google.com> wrote:

> Clang 12 generates a warning of:
> ./tracecmd/trace-stat.c:719:15: error: logical not is only applied to the left hand side of this comparison [-Werror,-Wlogical-not-parentheses]
>         if (clock && !strcmp(clock, "local") == 0)
>                      ^                       ~~
> ./tracecmd/trace-stat.c:719:15: note: add parentheses after the '!' to evaluate the comparison first
>         if (clock && !strcmp(clock, "local") == 0)
>                      ^
>                       (                          )
> ./tracecmd/trace-stat.c:719:15: note: add parentheses around left hand side expression to silence this warning
>         if (clock && !strcmp(clock, "local") == 0)
>                      ^
>                      (                      )
> 
> Silence by using "!= 0" as done elsewhere in the code.

Thanks, this does look like a nice clean up, and not just a removal of a
warning on Clang.

-- Steve


> 
> Signed-off-by: Ian Rogers <irogers@google.com>
> ---
>  tracecmd/trace-stat.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tracecmd/trace-stat.c b/tracecmd/trace-stat.c
> index 3112787..cb92622 100644
> --- a/tracecmd/trace-stat.c
> +++ b/tracecmd/trace-stat.c
> @@ -716,7 +716,7 @@ static void report_clock(struct buffer_instance *instance)
>  	clock = tracefs_get_clock(tracefs);
>  
>  	/* Default clock is "local", only show others */
> -	if (clock && !strcmp(clock, "local") == 0)
> +	if (clock && strcmp(clock, "local") != 0)
>  		printf("\nClock: %s\n", clock);
>  
>  	free(clock);