diff --git a/Zend/zend_compile.h b/Zend/zend_compile.h
index 9f76c78f0d3be..cc76dab9d7954 100644
--- a/Zend/zend_compile.h
+++ b/Zend/zend_compile.h
@@ -118,7 +118,9 @@ typedef struct _zend_file_context {
 } zend_file_context;
 
 typedef struct {
-	uint32_t offset;
+	/* Offset in bytes relative to the file start */
+	size_t offset;
+	/* This uses 32-bit integers to avoid doubling the size of the parser stack elements. */
 	uint32_t len;
 } zend_lexer_ident_ref;