Suppress zend_throw_error during preload constant resolution

Related to bug #77615.

Author: nikic

Zend/zend.c

@@ -1503,6 +1503,11 @@ ZEND_API ZEND_COLD void zend_throw_error(zend_class_entry *exception_ce, const c
 		exception_ce = zend_ce_error;
 	}
 
+	/* Marker used to disable exception generation during preloading. */
+	if (EG(exception) == (void*)(uintptr_t)-1) {
+		return;
+	}
+
 	va_start(va, format);
 	zend_vspprintf(&message, 0, format, va);
 

ext/opcache/ZendAccelerator.c

@@ -3453,11 +3453,11 @@ static void preload_link(void)
 			break;
 		}
 		if (!(ce->ce_flags & ZEND_ACC_LINKED)) {
-			zend_error(E_WARNING, "Can't preload unlinked class  %s at %s:%d\n", ZSTR_VAL(ce->name), ZSTR_VAL(ce->info.user.filename), ce->info.user.line_start);
+			zend_error(E_WARNING, "Can't preload unlinked class  %s at %s:%d", ZSTR_VAL(ce->name), ZSTR_VAL(ce->info.user.filename), ce->info.user.line_start);
 		} else if (!(ce->ce_flags & ZEND_ACC_CONSTANTS_UPDATED)) {
-			zend_error(E_WARNING, "Can't preload class %s with unresolved constants at %s:%d\n", ZSTR_VAL(ce->name), ZSTR_VAL(ce->info.user.filename), ce->info.user.line_start);
+			zend_error(E_WARNING, "Can't preload class %s with unresolved constants at %s:%d", ZSTR_VAL(ce->name), ZSTR_VAL(ce->info.user.filename), ce->info.user.line_start);
 		} else if (!(ce->ce_flags & ZEND_ACC_PROPERTY_TYPES_RESOLVED)) {
-			zend_error(E_WARNING, "Can't preload class %s with unresolved property types at %s:%d\n", ZSTR_VAL(ce->name), ZSTR_VAL(ce->info.user.filename), ce->info.user.line_start);
+			zend_error(E_WARNING, "Can't preload class %s with unresolved property types at %s:%d", ZSTR_VAL(ce->name), ZSTR_VAL(ce->info.user.filename), ce->info.user.line_start);
 		} else {
 			continue;
 		}

ext/opcache/tests/preload_004.phpt

@@ -0,0 +1,16 @@
+--TEST--
+Preloading class with undefined class constant access
+--INI--
+opcache.enable=1
+opcache.enable_cli=1
+opcache.optimization_level=-1
+opcache.preload={PWD}/preload_undef_const.inc
+--SKIPIF--
+<?php require_once('skipif.inc'); ?>
+--FILE--
+<?php
+var_dump(class_exists('Foo'));
+?>
+--EXPECTF--
+Warning: Can't preload class Foo with unresolved constants at %s:%d in Unknown on line 0
+bool(false)

ext/opcache/tests/preload_undef_const.inc

@@ -0,0 +1,4 @@
+<?php
+class Foo {
+    const A = self::DOES_NOT_EXIST;
+}