diff --git a/Zend/zend_globals.h b/Zend/zend_globals.h
index 4612198b44ca5..12e3c4a24303d 100644
--- a/Zend/zend_globals.h
+++ b/Zend/zend_globals.h
@@ -119,6 +119,7 @@ struct _zend_compiler_globals {
 	bool multibyte;
 	bool detect_unicode;
 	bool encoding_declared;
+	bool interned_strings_initialized;
 
 	zend_ast *ast;
 	zend_arena *ast_arena;
diff --git a/Zend/zend_string.c b/Zend/zend_string.c
index 1da3ce5248522..c605f431631e7 100644
--- a/Zend/zend_string.c
+++ b/Zend/zend_string.c
@@ -231,6 +231,9 @@ static zend_string* ZEND_FASTCALL zend_new_interned_string_request(zend_string *
 		return ret;
 	}
 
+	if (!CG(interned_strings_initialized)) {
+		zend_interned_strings_activate();
+	}
 	ret = zend_interned_string_ht_lookup(str, &CG(interned_strings));
 	if (ret) {
 		zend_string_release(str);
@@ -339,6 +342,7 @@ static zend_string* ZEND_FASTCALL zend_string_init_existing_interned_request(con
 ZEND_API void zend_interned_strings_activate(void)
 {
 	zend_init_interned_strings_ht(&CG(interned_strings), 0);
+	CG(interned_strings_initialized) = true;
 }
 
 ZEND_API void zend_interned_strings_deactivate(void)