https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118120
--- Comment #8 from kargls at comcast dot net ---
(In reply to anlauf from comment #7)
> The following patch works and might be a reasonable compromise:
>
> diff --git a/gcc/fortran/trans-array.cc b/gcc/fortran/trans-array.cc
> index 82a2ae1f747..985a26281ad 100644
> --- a/gcc/fortran/trans-array.cc
> +++ b/gcc/fortran/trans-array.cc
> @@ -5345,7 +5345,10 @@ symbols_could_alias (gfc_symbol *lsym, gfc_symbol
> *rsym, bool lsym_pointer,
> bool lsym_target, bool rsym_pointer, bool rsym_target)
> {
> /* Aliasing isn't possible if the symbols have different base types. */
> - if (gfc_compare_types (&lsym->ts, &rsym->ts) == 0)
> + if (!gfc_compare_types (&lsym->ts, &rsym->ts)
> + && !(((lsym->ts.type == BT_COMPLEX && rsym->ts.type == BT_REAL)
> + || (lsym->ts.type == BT_REAL && rsym->ts.type == BT_COMPLEX))
> + && lsym->ts.kind == rsym->ts.kind))
> return 0;
>
> /* Pointers can point to other pointers and target objects. */
I think it is more complicated in that this involves pointers, which
have an aliasing issue (due to bounds remapping). In an ordinary assignment
one has 'var = expr', and in Slava example that is exactly what we have
where 'result' and 'temp' are pointers into parts of 'data%re'. But,
'data%re' could have been any type compatible entity. The big hammer,
until the mythical someone shows up, is
diff --git a/gcc/fortran/trans-array.cc b/gcc/fortran/trans-array.cc
index 82a2ae1f747..abebf327621 100644
--- a/gcc/fortran/trans-array.cc
+++ b/gcc/fortran/trans-array.cc
@@ -5503,6 +5503,20 @@ gfc_conv_resolve_dependencies (gfc_loopinfo * loop,
gfc_ss * dest,
loop->temp_ss = NULL;
dest_expr = dest->info->expr;
+ /* Before falling into dependency checking of the scalarization,
+ check to see if the left-hand variable is an array pointer. If
+ it is, simply generate an array temporary for the assignment.
+ TODO: walk the right-hand-side of 'var = expr' to actually check
+ for a dependency. See 118120. */
+ if (dest_expr->symtree && dest_expr->symtree->n.sym
+ && dest_expr->symtree->n.sym->attr.pointer
+ && dest_expr->symtree->n.sym->attr.dummy
+ && dest_expr->symtree->n.sym->attr.dimension)
+ {
+ nDepend = 1;
+ goto temporary;
+ }
+
for (ss = rss; ss != gfc_ss_terminator; ss = ss->next)
{
ss_info = ss->info;
