[Bug fortran/30512] MAXVAL() incorrect for zero-size int arrays, and for -HUGE-1 maximum values.

["burnus at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #2 from burnus at gcc dot gnu dot org  2007-01-20 12:46 -------
Non-library part of this fix.
This fixes the reported bug, but libgfortran/m4/* should be fixed as well.

m4/iparm.m4 contains:
define(atype_max, atype_name`_HUGE')dnl
define(atype_min, `-'atype_max)dnl

One would need to put an "ifelse" for atype_min, but I'm rather illiterate in
m4.


Index: trans-intrinsic.c
===================================================================
--- trans-intrinsic.c   (Revision 120999)
+++ trans-intrinsic.c   (Arbeitskopie)
@@ -1976,11 +1976,16 @@
       gcc_unreachable ();
     }

-  /* Most negative(+HUGE) for maxval, most negative (-HUGE) for minval.  */
+  /* Most negative(-HUGE) for maxloc, most positiv (+HUGE) for minloc.  */
   if (op == GT_EXPR)
     tmp = fold_build1 (NEGATE_EXPR, TREE_TYPE (tmp), tmp);
   gfc_add_modify_expr (&se->pre, limit, tmp);

+  /* Most negative for BT_INTEGER is -HUGE-1.  */
+  if (op == GT_EXPR && expr->ts.type == BT_INTEGER)
+    tmp = build2 (MINUS_EXPR, TREE_TYPE (tmp), tmp,
+                 build_int_cst (type, 1));
+
   /* Initialize the scalarizer.  */
   gfc_init_loopinfo (&loop);
   gfc_add_ss_to_loop (&loop, arrayss);
@@ -2135,9 +2140,15 @@
       gcc_unreachable ();
     }

-  /* Most negative(-HUGE) for maxval, most positive (-HUGE) for minval.  */
+  /* Most negative(-HUGE) for maxval, most positive (+HUGE) for minval.  */
   if (op == GT_EXPR)
     tmp = fold_build1 (NEGATE_EXPR, TREE_TYPE (tmp), tmp);
+
+  /* Most negative for BT_INTEGER is -HUGE-1.  */
+  if (op == GT_EXPR && expr->ts.type == BT_INTEGER)
+    tmp = build2 (MINUS_EXPR, TREE_TYPE (tmp), tmp,
+                 build_int_cst (type, 1));
+
   gfc_add_modify_expr (&se->pre, limit, tmp);

   /* Walk the arguments.  */


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30512