[PATCH] Fix DWARF -g3 with - as source (PR debug/92664)

[Jeff Law]

On 11/26/19 4:45 PM, Jakub Jelinek wrote:
> Hi!
> 
> Without this patch, we emit in .debug_macro with -g3 -xc -
> a .file N "" directive which makes e.g. readelf unhappy.
> Elsewhere, we handle "" filename as "<stdin>", so this patch does that too
> for .debug_macro.
> 
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
> 
> 2019-11-27  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR debug/92664
> 	* dwarf2out.c (lookup_filename): Use "<stdin>" instead of "".
OK
jeff