[Bug driver/36312] should refuse to overwrite input file with output file

[manu at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=36312

--- Comment #22 from Manuel López-Ibáñez <manu at gcc dot gnu.org> ---
(In reply to Riccardo Mutschlechner from comment #21)
> Is this cruft, or something that would actually be used - and if so, what is
> a good way to go about doing this? 

https://gcc.gnu.org/wiki/GettingStarted#Basics:_Contributing_to_GCC_in_10_easy_steps