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Subject: [Bug libfortran/27524] -fbounds-check interracts *strangely* with an array of size 1
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------- Comment #3 from fxcoudert at gcc dot gnu dot org  2006-05-24 09:20 -------
>       function F()
>         integer :: F(1)
>         f = 1
>       end function F

Compiling this simple function without and with -fbounds-check and dumping the
GIMPLE tree generated gives the following diff:

--- 003t.original.noboundscheck 2006-05-24 11:09:37.000000000 +0200
+++ 003t.original.boundscheck   2006-05-24 11:09:32.000000000 +0200
@@ -14,8 +14,16 @@ f (__result)
     D.917 = __result->dim[0].stride;
     stride.0 = D.917 == 0 ? 1 : D.917;
     __result.0 = (int4[0:D.918] *) __result->data;
+    if ((logical4) __builtin_expect (__result->dim[0].ubound !=
__result->dim[0].lbound, 0))
+      {
+        _gfortran_runtime_error ("Array bound mismatch", "test.f90", 1);
+      }
+    else
+      {
+        (void) 0;
+      }
     size.2 = NON_LVALUE_EXPR <stride.0>;
-    offset.1 = -stride.0;
+    offset.1 = __result->dim[0].lbound - __result->dim[0].ubound;
     D.918 = size.2 - 1;
     D.919 = (bit_size_type) (<unnamed type>) size.2 * 


I think the cuplrit here is gfc_trans_dummy_array_bias(), around line 3728
(where the offset is built), although I'm not skilled enough in all this to
understand how exactly to fix it.


-- 

fxcoudert at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2006-05-19 16:59:16         |2006-05-24 09:20:48
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27524