Triggering -save-temps from the front-end code

[Florian Weimer]

* Arsen Arsenović:

> Hi,
>
> Florian Weimer via Gcc <gcc@gcc.gnu.org> writes:
>
>> Unfortunately, some build systems immediately delete the input source
>> files.  Is there some easy way I can dump the pre-processed and
>> non-preprocessed sources to my log file?  I tried to understand how
>> -save-temps for crash recovery works, but it seems that this runs
>> outside of the frontend, in the driver.
>
> Would dumping unconditionally into some "side channel" -dumpdir be a
> sufficient workaround?

Of the file names overlap, and it seems in this case, the dump files are
just overwritten.  I don't see a way to make the file names unique.

I guess for the tough cases, I can just keep running the build under
strace.

Thanks,
Florian