[Bug fortran/79430] [7/8 Regression] action of statement incorrectly optimised away

["juergen.reuter at desy dot de" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79430

--- Comment #65 from Jürgen Reuter <juergen.reuter at desy dot de> ---
(In reply to Thomas Koenig from comment #64)
> (In reply to Jürgen Reuter from comment #63)
> > (In reply to Thomas Koenig from comment #62)
> 
> > > I am currently at a loss how to proceed.
> > 
> > Darn.... Did you apply the patch from PR79344?
> 
> Yes.
> 

> +  IDENTIFIER  <variable>  = u
> *****************************************************************************
> *
> *** ERROR: This PDG-array variable is undefined at this point
> *****************************************************************************

There is obviously something wrong.

> Oh well... maybe I will bisect that one first, to find out what
> went wrong there, and then another bisection to find out which patch
> fixed that, and then....

There were 4 regressions ca. 12/2016 that I can remember that affected our
code: 1) PR79229 which started in r241439 but affected only -fcheck=mem, fixed
in r245581
2) PR79230, started with r243480, affected many tests generally, fixed in
r245191
3) PR79344, started with r242875. affected many things, fixed in r245194.
4) this ugly one here. 
There is another one (PR80361), which is older, and affects only
-fcheck=recursive. 
From what I can see these are all.