[Bug fortran/59016] f951: internal compiler error: Segmentation fault

["dominiq at lps dot ens.fr" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59016

--- Comment #18 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
With an additional filtering on (m == MATCH_ERROR), i.e. with the following
patch, the ICEs are fixed without regression

--- ../_clean/gcc/fortran/decl.c    2015-03-25 14:07:04.000000000 +0100
+++ gcc/fortran/decl.c    2015-04-05 16:17:34.000000000 +0200
@@ -4427,6 +4437,32 @@ ok:
   gfc_free_data_all (gfc_current_ns);

 cleanup:
+  //<pr59016> in gfc_match_data_decl; cleanup the garbages  
+  gfc_symbol *csym = NULL;
+  if ((m == MATCH_ERROR) && current_ts.u.derived
+      && current_ts.u.derived->name)
+    {
+      char iname[129];
+      iname[128] = 0;
+      for (int i = 0; i < 128; i++)
+    {
+      iname[i] = current_ts.u.derived->name[i];
+      if (current_ts.u.derived->name[i] == 0)
+        break;
+    }
+      iname[0] = TOLOWER(iname[0]);
+      for (int i = 0; i < 4; i++)
+    {
+     gfc_find_symbol (iname, NULL, i, &csym) ;
+     if (csym && csym->generic
+         && (csym->generic->sym == current_ts.u.derived))
+       {
+          csym->generic = NULL;
+          break;
+       }
+    }
+    }
+  //</pr59016>
   gfc_free_array_spec (current_as);
   current_as = NULL;
   return m;

Further testing in progress. A few comments:

(1) The patch could probably be simplified,
(2) Its conformity with the GNU coding style has to be checked.
(3) It has to go to fortran@gcc.gnu.org and gcc-patches@gcc.gnu.org for review.