[PATCH, v2] Fortran: diagnose strings of non-constant length in DATA statements [PR68569]

[Harald Anlauf <anlauf@gmx.de>]

[-- Attachment #1: Type: text/plain, Size: 440 bytes --]

Dear all,

the original submission missed the adjustments of the expected
patterns of 2 tests.  This is corrected in the new attachments.

Am 26.07.23 um 21:10 schrieb Harald Anlauf via Gcc-patches:
> Dear all,
>
> the attached patch fixes an ICE-on-invalid after use of strings of
> non-constant length in DATA statements.
>
> Regtested on x86_64-pc-linux-gnu.  OK for mainline?
>
> Thanks,
> Harald
>

Thanks,
Harald


[-- Attachment #2: pr68569-v2.patch --]
[-- Type: text/x-patch, Size: 1415 bytes --]

diff --git a/gcc/fortran/resolve.cc b/gcc/fortran/resolve.cc
index f7cfdfc133f..cd8e223edce 100644
--- a/gcc/fortran/resolve.cc
+++ b/gcc/fortran/resolve.cc
@@ -16771,7 +16787,6 @@ check_data_variable (gfc_data_variable *var, locus *where)
     return false;
 
   ar = NULL;
-  mpz_init_set_si (offset, 0);
   e = var->expr;
 
   if (e->expr_type == EXPR_FUNCTION && e->value.function.isym
@@ -16838,8 +16853,24 @@ check_data_variable (gfc_data_variable *var, locus *where)
 		     "attribute", ref->u.c.component->name, &e->where);
 	  return false;
 	}
+
+      /* Reject substrings of strings of non-constant length.  */
+      if (ref->type == REF_SUBSTRING
+	  && ref->u.ss.length
+	  && ref->u.ss.length->length
+	  && !gfc_is_constant_expr (ref->u.ss.length->length))
+	goto bad_charlen;
     }
 
+  /* Reject deferred length character and strings of non-constant length.  */
+  if (e->ts.type == BT_CHARACTER
+      && (e->ts.deferred
+	  || (e->ts.u.cl->length
+	      && !gfc_is_constant_expr (e->ts.u.cl->length))))
+    goto bad_charlen;
+
+  mpz_init_set_si (offset, 0);
+
   if (e->rank == 0 || has_pointer)
     {
       mpz_init_set_ui (size, 1);
@@ -16967,6 +16998,11 @@ check_data_variable (gfc_data_variable *var, locus *where)
   mpz_clear (offset);
 
   return t;
+
+bad_charlen:
+  gfc_error ("Non-constant character length at %L in DATA statement",
+	     &e->where);
+  return false;
 }