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Author: sj-i

Zend/zend_compile.c

@@ -1595,6 +1595,9 @@ static bool zend_try_compile_const_expr_resolve_class_name(zval *zv, zend_ast *c
 static bool zend_verify_ct_const_access(zend_class_constant *c, zend_class_entry *scope)
 {
 	if (c->ce->ce_flags & ZEND_ACC_TRAIT) {
+		/* This condition is only met on directly accessing trait constants,
+		 * because the ce is replaced to the class entry of the composing class
+		 * on binding. */
 		return 0;
 	} else if (ZEND_CLASS_CONST_FLAGS(c) & ZEND_ACC_PUBLIC) {
 		return 1;

Zend/zend_constants.c

@@ -362,6 +362,7 @@ ZEND_API zval *zend_get_class_constant_ex(zend_string *class_name, zend_string *
 			}
 
 			if (UNEXPECTED(ce->ce_flags & ZEND_ACC_TRAIT)) {
+				/** Prevent accessing trait constants directly on cases like \defined() or \constant(), etc. */
 				if ((flags & ZEND_FETCH_CLASS_SILENT) == 0) {
 					zend_throw_error(NULL, "Cannot access trait constant %s::%s directly", ZSTR_VAL(class_name), ZSTR_VAL(constant_name));
 				}