From: Xinchen Hui <laruence@gmail.com>
Date: Tue, 20 Dec 2016 13:01:21 +0000 (+0800)
Subject: Fixed bug #73789 (Strange behavior of class constants in switch/case block)
X-Git-Tag: php-7.1.1RC1~71
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6bd41a1d47417ad2c7938a57c8abca4e210d5cf6;p=php

Fixed bug #73789 (Strange behavior of class constants in switch/case block)
---

diff --git a/NEWS b/NEWS
index 9e1cbf2b11..f94dd9aa9c 100644
--- a/NEWS
+++ b/NEWS
@@ -26,6 +26,8 @@ PHP                                                                        NEWS
     usage. (Andrey)
 
 - Opcache:
+  . Fixed bug #73789 (Strange behavior of class constants in switch/case block).
+    (Laruence)
   . Fixed bug #73746 (Method that returns string returns UNKNOWN:0 instead).
     (Laruence)
   . Fixed bug #73654 (Segmentation fault in zend_call_function). (Nikita)
diff --git a/ext/opcache/Optimizer/dfa_pass.c b/ext/opcache/Optimizer/dfa_pass.c
index b7a0f065f7..2780a4cc54 100644
--- a/ext/opcache/Optimizer/dfa_pass.c
+++ b/ext/opcache/Optimizer/dfa_pass.c
@@ -569,19 +569,23 @@ void zend_dfa_optimize_op_array(zend_op_array *op_array, zend_optimizer_ctx *ctx
 // op_1: VERIFY_RETURN_TYPE #orig_var.CV [T] -> #v.CV [T] => NOP
 
 				int orig_var = ssa->ops[op_1].op1_use;
-				int ret = ssa->vars[v].use_chain;
+				if (zend_ssa_unlink_use_chain(ssa, op_1, orig_var)) {
 
-				ssa->vars[orig_var].use_chain = ret;
-				ssa->ops[ret].op1_use = orig_var;
+					int ret = ssa->vars[v].use_chain;
 
-				ssa->vars[v].definition = -1;
-				ssa->vars[v].use_chain = -1;
+					ssa->ops[ret].op1_use = orig_var;
+					ssa->ops[ret].op1_use_chain = ssa->vars[orig_var].use_chain;
+					ssa->vars[orig_var].use_chain = ret;
 
-				ssa->ops[op_1].op1_def = -1;
-				ssa->ops[op_1].op1_use = -1;
+					ssa->vars[v].definition = -1;
+					ssa->vars[v].use_chain = -1;
+
+					ssa->ops[op_1].op1_def = -1;
+					ssa->ops[op_1].op1_use = -1;
 
-				MAKE_NOP(opline);
-				remove_nops = 1;
+					MAKE_NOP(opline);
+					remove_nops = 1;
+				}
 
 			} else if (ssa->ops[op_1].op1_def == v
 			 && !RETURN_VALUE_USED(opline)
diff --git a/ext/opcache/tests/bug73789.phpt b/ext/opcache/tests/bug73789.phpt
new file mode 100644
index 0000000000..142d5229f9
--- /dev/null
+++ b/ext/opcache/tests/bug73789.phpt
@@ -0,0 +1,30 @@
+--TEST--
+Bug #73789 (Strange behavior of class constants in switch/case block)
+--FILE--
+<?php
+class Lexer
+{
+	const T_NONE = 1;
+	const T_STRING = 2;
+	const T_DOT = 8;
+	public function getType($value): int
+	{
+		$type = self::T_NONE;
+		switch (true) {
+		case ctype_alpha($value[0]):
+			$name = 'Lexer::T_' . strtoupper($value);
+			$type = constant($name);
+			if ($type > 100) {
+				return $type;
+			}
+			return self::T_STRING;
+		case $value === '.':
+			return self::T_DOT;
+		default:
+		}
+		return $type;
+	}
+}
+var_dump((new Lexer())->getType("dot"));
+--EXPECT--
+int(2)