[Patch, gfortran] PR22304, 17917, 16511, 18870 and 23270 - modules, equivalences and commons

[Paul Thomas]

Steven,

>>
>> What if the equivalenced sym is defined in the parent name space, or
>> is that impossible?
>>
14.6.3.3  "An EQUIVALENCE statement causes storage association of data 
objects only within one scoping unit, unless one of the equivalenced 
entities is also in a common block (5.5.1.1 and 5.5.2.1)."

program foo
  common /x/ a
  a = 1
  call bar ()
contains
  subroutine bar ()
  equivalence (a,b)
    print *, b
  end subroutine bar
end program foo

Should print the uninitialised value for b.  Thus, ifc prints out    
0.000000E+00.  gfortran segfaults, unless the "common /x/ a" is 
commented out.  It then does the right thing. Alternatively, declaring a 
to be real, before the equivalence, also works.

I will add a PR for his one and will put it on the list of things to do, 
when I get back.  I think that it should be fixed separately to the 
above patch, though.

I have to go NOW....

Regards

Paul T