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Subject: [Patch] x % 0 hangs
From: David Lecomber <david@streamline-computing.com>
To: gdb-patches@sources.redhat.com
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Date: Sat, 26 Jun 2004 09:23:00 -0000
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Hi

On my x86, gdb does not enjoy evaluating x % 0 or x / 0 for any x: it
hangs.

Although there may be some systems that can healthily respond to this, I
propose a trivial patch - unless someone is going to tell me there's an
option to stop the hanging, or respond differently to the signal.

2004-06-26    <david@streamline-computing.com>

	* valarith.c: check for zero in division and remainder
	evaluation.

Index: valarith.c
===================================================================
RCS file: /cvs/src/src/gdb/valarith.c,v
retrieving revision 1.22
diff -u -p -r1.22 valarith.c
--- valarith.c  1 Apr 2004 12:08:30 -0000       1.22
+++ valarith.c  26 Jun 2004 09:21:31 -0000
@@ -1040,7 +1040,10 @@ value_binop (struct value *arg1, struct
              break;
  
            case BINOP_DIV:
-             v = v1 / v2;
+             if (v2 != 0)
+               v = v1 / v2;
+             else
+               error ("Cannot perform division: division by zero");
               break;
  
             case BINOP_EXP:
@@ -1050,7 +1053,10 @@ value_binop (struct value *arg1, struct
              break;
  
            case BINOP_REM:
-             v = v1 % v2;
+             if (v2 != 0)
+               v = v1 % v2;
+             else
+               error ("Cannot perform remainer: division by zero");
              break;
  
            case BINOP_MOD: