[Bug fortran/41922] Diagnostic: No location shown for overlappingly initialized EQUIVALENCEd character vars

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=41922

--- Comment #3 from kargl at gcc dot gnu.org ---
Index: target-memory.h
===================================================================
--- target-memory.h     (revision 237855)
+++ target-memory.h     (working copy)
@@ -44,7 +44,7 @@ int gfc_interpret_derived (unsigned char
 int gfc_target_interpret_expr (unsigned char *, size_t, gfc_expr *, bool);

 /* Merge overlapping equivalence initializers for trans-common.c. */
-size_t gfc_merge_initializers (gfc_typespec, gfc_expr *,
+size_t gfc_merge_initializers (gfc_typespec, gfc_expr *, locus *,
                               unsigned char *, unsigned char *,
                               size_t);

Index: target-memory.c
===================================================================
--- target-memory.c     (revision 237855)
+++ target-memory.c     (working copy)
@@ -639,7 +639,8 @@ gfc_target_interpret_expr (unsigned char
    error.  */

 static size_t
-expr_to_char (gfc_expr *e, unsigned char *data, unsigned char *chk, size_t
len)
+expr_to_char (gfc_expr *e, locus *loc,
+             unsigned char *data, unsigned char *chk, size_t len)
 {
   int i;
   int ptr;
@@ -663,7 +664,7 @@ expr_to_char (gfc_expr *e, unsigned char
            continue;
          ptr = TREE_INT_CST_LOW(DECL_FIELD_OFFSET(cmp->backend_decl))
            + TREE_INT_CST_LOW(DECL_FIELD_BIT_OFFSET(cmp->backend_decl))/8;
-         expr_to_char (c->expr, &data[ptr], &chk[ptr], len);
+         expr_to_char (c->expr, loc, &data[ptr], &chk[ptr], len);
        }
       return len;
     }
@@ -674,12 +675,16 @@ expr_to_char (gfc_expr *e, unsigned char
   buffer = (unsigned char*)alloca (len);
   len = gfc_target_encode_expr (e, buffer, len);

-    for (i = 0; i < (int)len; i++)
+  for (i = 0; i < (int)len; i++)
     {
       if (chk[i] && (buffer[i] != data[i]))
        {
-         gfc_error ("Overlapping unequal initializers in EQUIVALENCE "
-                    "at %L", &e->where);
+         if (loc)
+           gfc_error ("Overlapping unequal initializers in EQUIVALENCE "
+                       "at %L", loc);
+         else
+           gfc_error ("Overlapping unequal initializers in EQUIVALENCE "
+                       "at %C");
          return 0;
        }
       chk[i] = 0xFF;
@@ -695,7 +700,8 @@ expr_to_char (gfc_expr *e, unsigned char
    the union declaration.  */

 size_t
-gfc_merge_initializers (gfc_typespec ts, gfc_expr *e, unsigned char *data,
+gfc_merge_initializers (gfc_typespec ts, gfc_expr *e, locus *loc,
+                       unsigned char *data,
                        unsigned char *chk, size_t length)
 {
   size_t len = 0;
@@ -705,8 +711,7 @@ gfc_merge_initializers (gfc_typespec ts,
     {
     case EXPR_CONSTANT:
     case EXPR_STRUCTURE:
-      len = expr_to_char (e, &data[0], &chk[0], length);
-
+      len = expr_to_char (e, loc, &data[0], &chk[0], length);
       break;

     case EXPR_ARRAY:
@@ -718,7 +723,7 @@ gfc_merge_initializers (gfc_typespec ts,
          if (mpz_cmp_si (c->offset, 0) != 0)
            len = elt_size * (size_t)mpz_get_si (c->offset);

-         len = len + gfc_merge_initializers (ts, c->expr, &data[len],
+         len = len + gfc_merge_initializers (ts, c->expr, loc, &data[len],
                                              &chk[len], length - len);
        }
       break;
Index: trans-common.c
===================================================================
--- trans-common.c      (revision 237855)
+++ trans-common.c      (working copy)
@@ -532,10 +532,15 @@ get_init_field (segment_info *head, tree
   memset (chk, '\0', (size_t)length);
   for (s = head; s; s = s->next)
     if (s->sym->value)
-      gfc_merge_initializers (s->sym->ts, s->sym->value,
+      {
+       locus *loc = NULL;
+       if (s->sym->ns->equiv && s->sym->ns->equiv->eq)
+         loc = &s->sym->ns->equiv->eq->expr->where;
+       gfc_merge_initializers (s->sym->ts, s->sym->value, loc,
                              &data[s->offset],
                              &chk[s->offset],
                             (size_t)s->length);
+      }

   for (i = 0; i < length; i++)
     CONSTRUCTOR_APPEND_ELT (v, NULL, build_int_cst (type, data[i]));