Namelist IOSTAT behaviour

[Paul Thomas]

Steve,

> looking at a problem with "USE, only : a => z, b => z" where
> the "b => z" causes an ICE because the "a => z" removes z from
> the symbols in the module.  

I think that I can fix that but is it legal? It's a bit bizarre to tie two
host symbols to one module variable, isn't it?  Is there an associated PR?

> I also tried to understand the 
> problem with EQUIVALENCE in modules.  I gave up. ;-(

This looks as if it is a problem of logic in trans_decl.c, rather than in
module.c.  The error is generated because the equivalenced variable is found
to already have a backend_decl by the time gfc_create_module_variable is
called. I'll have a poke around; the odd thing is that it was a bug that
appeared.

In a similar vein, PR19561 seems to have done the opposite and fixed itself
spontaneously. Is somebody owning up or is this due to Tobi's and my
rummaging around with dereferencing? Either way, I propose to write a test
case so that it is nailed to the floor.

Paul T