Fix phpGH-18899: JIT function crash when emitting undefined variable warning and opline is not set yet

The crash happens because EX(opline) is attempted to be accessed but
it's not set yet.

Closes phpGH-18904.

Author: nielsdos

NEWS

@@ -24,6 +24,8 @@ PHP                                                                        NEWS
 - Opcache:
   . Fixed bug GH-18639 (Internal class aliases can break preloading + JIT).
     (nielsdos)
+  . Fixed bug GH-18899 (JIT function crash when emitting undefined variable
+    warning and opline is not set yet). (nielsdos)
 
 - Standard:
   . Fix misleading errors in printf(). (nielsdos)

ext/opcache/jit/zend_jit_ir.c

@@ -5981,6 +5981,7 @@ static int zend_jit_long_math_helper(zend_jit_ctx   *jit,
 			ir_IF_FALSE_cold(if_def);
 
 			// zend_error_unchecked(E_WARNING, "Undefined variable $%S", CV_DEF_OF(EX_VAR_TO_NUM(opline->op1.var)));
+			jit_SET_EX_OPLINE(jit, opline);
 			ir_CALL_1(IR_VOID, ir_CONST_FC_FUNC(zend_jit_undefined_op_helper), ir_CONST_U32(opline->op1.var));
 
 			ref2 = jit_EG(uninitialized_zval);
@@ -5997,6 +5998,7 @@ static int zend_jit_long_math_helper(zend_jit_ctx   *jit,
 			ir_IF_FALSE_cold(if_def);
 
 			// zend_error_unchecked(E_WARNING, "Undefined variable $%S", CV_DEF_OF(EX_VAR_TO_NUM(opline->op2.var)));
+			jit_SET_EX_OPLINE(jit, opline);
 			ir_CALL_1(IR_VOID, ir_CONST_FC_FUNC(zend_jit_undefined_op_helper), ir_CONST_U32(opline->op2.var));
 
 			ref2 = jit_EG(uninitialized_zval);

ext/opcache/tests/jit/gh18899.phpt

@@ -0,0 +1,21 @@
+--TEST--
+GH-18899 (JIT function crash when emitting undefined variable warning and opline is not set yet)
+--EXTENSIONS--
+opcache
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.jit=1205
+opcache.jit_buffer_size=8M
+--FILE--
+<?php
+function ptr2str()
+{
+    for ($i=0; $i<8; $i++) {
+        $ptr >>= 8;
+    }
+}
+str_repeat("A",232).ptr2str();
+?>
+--EXPECTF--
+Warning: Undefined variable $ptr in %s on line %d