MFB: Fixed bug #28800 (strings beginning with "inf" improperly converted).

Zend/zend_operators.h

@@ -87,6 +87,8 @@ static inline zend_bool is_numeric_string(char *str, int length, long *lval, dou
 				*lval = local_lval;
 			}
 			return IS_LONG;
+		} else if (end_ptr_long == str && *end_ptr_long != '\0') { /* ignore partial string matches */
+			return 0;
 		}
 	} else {
 		end_ptr_long=NULL;

tests/lang/bug28800.phpt

@@ -0,0 +1,17 @@
+--TEST--
+Bug #28800 (Incorrect string to number conversion for strings starting with 'inf')
+--FILE--
+<?php
+	$strings = array('into', 'info', 'inf', 'infinity', 'infin', 'inflammable');
+	foreach ($strings as $v) {
+		echo ($v+0)."\n";
+	}
+?>
+--EXPECT--
+0
+0
+0
+0
+0
+0
+