diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/bug785175.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/bug785175.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,9 @@
+var str = ' ';
+// Generate a 4MB string = 2^(20+2)
+for (var i = 0; i < 22; i++) {
+    str = str + str;
+}
+str += 'var a = 1 + 1;';
+
+// don't throw an exception even though the column numbers cannot be maintained
+eval(str);