# HG changeset patch
# User William Astle <lost@l-w.ca>
# Date 1359607635 25200
# Node ID bc25269d96bc53d5413376cd13f2d948e9543b0e
# Parent  67acad9db5b35a063da368d4a1dd2471108a84d1
Fix crash on expression range calculation

When attempting to calculate the range of a NULL expression, just indicate
failure and bail out rather than dereferencing the expression and crashing
out with no feedback.

diff -r 67acad9db5b3 -r bc25269d96bc lwasm/lwasm.c
--- a/lwasm/lwasm.c	Wed Jan 30 21:40:34 2013 -0700
+++ b/lwasm/lwasm.c	Wed Jan 30 21:47:15 2013 -0700
@@ -1077,6 +1077,9 @@
 	rd.max = 0;
 	rd.as = as;
 	
+	if (!expr)
+		return -1;
+	
 	lw_expr_testterms(expr, lwasm_calculate_range_tf, (void *)&rd);
 	*min = rd.min;
 	*max = rd.max;