[Bug tree-optimization/40635] [12 Regression] bogus name and location in 'may be used uninitialized' warning

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=40635

--- Comment #19 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Martin Sebor from comment #18)
> The location is still present at g:45f4e2b01b82c72b3a11ff4ad184d7edcf0e63d4
> but is lost after:
> 
> commit 9f55df63154a39d67ef5b24def7044bf87300831
> Author: Andrew Pinski <apinski@marvell.com>
> Date:   Tue Jun 1 01:05:09 2021 +0000
> 
>     Replace conditional_replacement with match and simplify
>     
>     This is the first of series of patches to simplify phi-opt
>     to use match and simplify in many cases.  This simplification
>     will more things to optimize.

Yes this part is the missing part:
-      /* Set the locus to the first argument, unless is doesn't have one.  */
-      locus_0 = gimple_phi_arg_location (phi, 0);
-      locus_1 = gimple_phi_arg_location (phi, 1);
-      if (locus_0 == UNKNOWN_LOCATION)
-        locus_0 = locus_1;
-      gimple_set_location (new_stmt, locus_0);

Let me look over the weekend.