merge revision(s) 66736: [Backport #15511]

	ast.c: argument must be a string

	[ruby-core:90904] [Bug #15511]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_6@66827 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 1 deletions

diff --git a/ast.c b/ast.c
index c3f28eba0b..2df4bdd870 100644
--- a/ast.c
+++ b/ast.c
@@ -96,7 +96,7 @@ rb_ast_parse_str(VALUE str)
 {
     rb_ast_t *ast = 0;
 
-    str = rb_check_string_type(str);
+    StringValue(str);
     ast = rb_parser_compile_string_path(ast_parse_new(), Qnil, str, 1);
     return ast_parse_done(ast);
 }