Merge branch 'PHP-7.4'

Author: nikic

ext/opcache/Optimizer/dfa_pass.c

@@ -830,6 +830,7 @@ static int zend_dfa_optimize_jmps(zend_op_array *op_array, zend_ssa *ssa)
 							MAKE_NOP(opline);
 							removed_ops++;
 							take_successor_1(ssa, block_num, block);
+							zend_ssa_remove_result_def(ssa, ssa_op);
 							goto optimize_nop;
 						}
 					}

ext/opcache/tests/opt/jmp_001.phpt

@@ -0,0 +1,30 @@
+--TEST--
+JMP 001: JMP_SET with constant arg
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.optimization_level=-1
+opcache.opt_debug_level=0x20000
+--SKIPIF--
+<?php require_once('skipif.inc'); ?>
+--FILE--
+<?php
+function test() {
+    $var = null;
+    $var = $var ?: test2();
+    return $var;
+}
+?>
+--EXPECTF--
+$_main: ; (lines=1, args=0, vars=0, tmps=0)
+    ; (after optimizer)
+    ; %s:1-8
+L0 (8):     RETURN int(1)
+
+test: ; (lines=4, args=0, vars=1, tmps=1)
+    ; (after optimizer)
+    ; %s:2-6
+L0 (4):     INIT_FCALL_BY_NAME 0 string("test2")
+L1 (4):     V1 = DO_FCALL_BY_NAME
+L2 (4):     CV0($var) = QM_ASSIGN V1
+L3 (5):     RETURN CV0($var)