From: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date: Tue, 18 Oct 2022 09:23:10 GMT
Subject: Re: [RFC PATCH 2/2] notes.c: fixed tip when target and append note are both empty
Message-ID: <221018.864jw1jxfx.gmgdl@evledraar.gmail.com>
In-Reply-To: <20221018031144.73730-1-tenglong.tl@alibaba-inc.com>


On Tue, Oct 18 2022, Teng Long wrote:

> "Ævar Arnfjörð Bjarmason" <avarab@gmail.com> writes:
>
>> Hrm, interesting that (at least my) gcc doesn't catch if we don't
>> NULL-initialize this, but -fanalyzer does (usually it's not needed for
>> such trivial cases0. Anyawy...
>
> On my local env the warnings shows , show I change the line (initialize with
> NULL to "logmsg").
>
> But it seems like different as the last time I built... However now "suggest
> braces around initialization of subobject" appears, is it normal or we should
> repair this?
>
> builtin/merge-file.c:29:23: warning: suggest braces around initialization of subobject [-Wmissing-braces]
>         mmfile_t mmfs[3] = { 0 };
>                              ^
>                              {}
> builtin/merge-file.c:31:20: warning: suggest braces around initialization of subobject [-Wmissing-braces]
>         xmparam_t xmp = { 0 };
>                           ^
>                           {}

The fix for this is in "next": 54795d37d9e (config.mak.dev: disable
suggest braces error on old clang versions, 2022-10-10)


> 2 warnings generated.
> builtin/notes.c:641:13: warning: variable 'logmsg' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
>         } else if (!cp.buf.len) {
>                    ^~~~~~~~~~~
> builtin/notes.c:653:7: note: uninitialized use occurs here
>         free(logmsg);
>              ^~~~~~
> builtin/notes.c:641:9: note: remove the 'if' if its condition is always false
>         } else if (!cp.buf.len) {
>                ^~~~~~~~~~~~~~~~~~
> builtin/notes.c:570:14: note: initialize the variable 'logmsg' to silence this warning
>         char *logmsg;
>                     ^
>                      = NULL
> 1 warning generated.

Yes, we should initialize it to NULL, so this is the expected
warning. Clang spots it.