[Bug fortran/84394] compiler error when using modules with derived types in block data subprograms

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84394

--- Comment #2 from kargl at gcc dot gnu.org ---
(In reply to kargl from comment #1)

> Breakpoint 1, check_conflict (attr=attr@entry=0x203caec38, 
>     name=0x203c22430 "_deallocate", where=where@entry=0x203caec78)
>     at ../../gcc/gcc/fortran/symbol.c:485
> 485               gfc_error("%s attribute not allowed in BLOCK DATA program "
> (gdb) p *where
> $1 = {nextc = 0x0, lb = 0x0}
> 
> So, gfortran is inserting a _deallocate (perhaps for a temporary array).
> I suspect were can the conflict check for a name starting with an
> underscore.

I forgot to mention that attr->access = ACCESS_PRIVATE, which
the actual root cause.  I also suspect that the attr is re-using
a previous attr struct without clear it first.   In any case, the
following works around the problem.


Index: symbol.c
===================================================================
--- symbol.c    (revision 257665)
+++ symbol.c    (working copy)
@@ -479,11 +479,10 @@ check_conflict (symbol_attribute *attr, const char *na
       if (attr->intent != INTENT_UNKNOWN)
        a1 = intent;

-      if (a1 != NULL)
+      if (a1 != NULL && *name != '_')
        {
-         gfc_error
-           ("%s attribute not allowed in BLOCK DATA program unit at %L",
-            a1, where);
+         gfc_error("%s attribute not allowed in BLOCK DATA program "
+                   "unit at %L", a1, where);
          return false;
        }
     }