Re: [PATCH] Fix gdb crash due to SIGPIPE when the compile command fails

[Bernd Edlinger <bernd.edlinger@hotmail.de>]

On 6/15/21 1:35 AM, Pedro Alves wrote:
> On 2021-06-04 2:39 p.m., Tom Tromey wrote:
>>>>>>> "Bernd" == Bernd Edlinger <bernd.edlinger@hotmail.de> writes:
>>
>> Bernd> I believe it is right to avoid the SIGPIPE before calling the plugin,
>> Bernd> instead of doing that in gcc-trunk, since we don't know which version
>> Bernd> we will be calling, and all versions I tried have failed like this.
>>
>> That seems fine, but I think it would be better to install the handler
>> just when working with the plugin, and then uninstall it afterward, sort
>> of like what class scoped_ignore_sigttou does.
> 
> One thing I dislike here (and also about scoped_ignore_sigttou), is that the
> signal disposition is process-wide.  
> 
> If we happen to have multiple threads that need to ignore the signal changing the
> disposition like that, then they may race.
> 
> We can fix that by making the ignoring be per-thread instead by using
> sigprocmask + sigtimedwait.  
> 
> We can also introduce a generic scoped_ignore_signal so that both scoped_ignore_sigttou
> and scoped_ignore_pipe (and whatever other similar signal we may need to ignore) share
> the same code.  
> 
> I gave it a quick try.  See the 4 patches at the top of the
> users/palves/scoped_ignore_signal branch.
> 
> This was something that I've thought before about doing for SIGTTOU to be honest.
> Seeing it being copied over to SIGPIPE was simply the trigger that made me
> actually give it a try.  
> 
> WDYT?
> 

+1

Thanks
Bernd.

> Pedro Alves
>