Re: [PATCH] kconfig: plug false-positive warning in get_prompt_str() seen with gcc-4.9

From: David Rientjes
Date: Mon Jun 23 2014 - 05:29:53 EST


On Mon, 23 Jun 2014, Uwe Kleine-KÃnig wrote:

> > scripts/kconfig/menu.c: In function âget_symbol_strâ:
> > scripts/kconfig/menu.c:590:18: warning: âjumpâ may be used uninitialized in this function [-Wmaybe-uninitialized]
> > jump->offset = strlen(r->s);
> > ^
> > scripts/kconfig/menu.c:551:19: note: âjumpâ was declared here
> > struct jump_key *jump;
> > ^
>
> I'm seeing that problem with a 4.8.2 toolchain on next-20140623 with
> ARCH=arm, too.
>
> Maybe better use uninitialized_var? And point out the commit that
> introduced the issue please.
>

If the compiler can't figure out if a variable is always intialized before
its referenced, then it indicates the code is poorly written and isn't
clear to the code reader either. uninitialized_var() would be a lazy way
to solve this particular issue.