Re: [PATCH] [PERF] (Userspace Tools) Fix a compilation error with -fstack-protector and -Werror

["Américo Wang" <xiyou.wangcong@gmail.com>]

On Tue, Oct 19, 2010 at 08:40:00AM +0200, Ingo Molnar wrote:
>
>* Brian Gitonga Marete <marete@toshnix.com> wrote:
>
>> On Tue, Oct 19, 2010 at 2:38 AM, Frederic Weisbecker <fweisbec@gmail.com> wrote:
>> > On Tue, Oct 19, 2010 at 02:24:00AM +0300, Brian Gitonga Marete wrote:
>> >> The following patch fixes compilation of the perf user-space tools on,
>> >> for example, gcc version 4.3.3 (Ubuntu 4.3.3-5ubuntu4) . It should not
>> >> break anything else.
>> >
>> >
>> >
>> > Hi,
>> >
>> > What kind of warning have you encountered and why it fixes it?
>> > Can you describe that in your changelog?
>> >
>> 
>> Hello Frederic,
>> 
>> Some versions of gcc, e.g. gcc version 4.3.3 (Ubuntu 4.3.3-5ubuntu4), have the 
>> (default) minimum size of buffers protected by `-fstack-protector' set to 8. But 
>> in perf, there exist much smaller automatic buffers.
>
>Hm, it's this code:
>
>        /* newtWinChoice should really be accepting const char pointers... */
>        char yes[] = "Yes", no[] = "No";
>        return newtWinChoice(NULL, yes, no, (char *)msg) == 1;
>
>I.e. the code is messy and GCC is right to warn about it. Hence it would be somewhat 
>bad to actually remove the warning that pointed out some dodgy piece of code.

Agreed.

>
>Even if marking it const doesnt work due to the external libnewt API, we could at 
>least put 'yes' and 'no' into file scope and mark them static?
>

How about making ui__dialog_yesno() a macro? ;) Like:

#define ui__dialog_yesno(msg) \
	({newWinChoice(NULL, "Yes", "No", (char *)(msg)) == 1;})