svn commit: r227369 - head/bin/sh

[Jilles Tjoelker]

Author: jilles
Date: Tue Nov  8 23:54:39 2011
New Revision: 227369
URL: http://svn.freebsd.org/changeset/base/227369

Log:
  sh: Remove undefined behaviour due to overflow in +/-/* in arithmetic.
  
  With i386 base gcc and i386 base clang, arith_yacc.o remains unchanged.

Modified:
  head/bin/sh/arith_yacc.c

Modified: head/bin/sh/arith_yacc.c
==============================================================================
--- head/bin/sh/arith_yacc.c	Tue Nov  8 23:44:26 2011	(r227368)
+++ head/bin/sh/arith_yacc.c	Tue Nov  8 23:54:39 2011	(r227369)
@@ -131,11 +131,11 @@ static arith_t do_binop(int op, arith_t 
 			yyerror("divide error");
 		return op == ARITH_REM ? a % b : a / b;
 	case ARITH_MUL:
-		return a * b;
+		return (uintmax_t)a * (uintmax_t)b;
 	case ARITH_ADD:
-		return a + b;
+		return (uintmax_t)a + (uintmax_t)b;
 	case ARITH_SUB:
-		return a - b;
+		return (uintmax_t)a - (uintmax_t)b;
 	case ARITH_LSHIFT:
 		return a << b;
 	case ARITH_RSHIFT: