Revert "Revert "Fix dangling path name from fstring""

This reverts commit 326c00b6f89e1c86e6fe29ab60da593eb6883a88.

We also confirmed that test_gced_eval_location fails without the changes:
https://travis-ci.org/ruby/ruby/builds/567417818
https://rubyci.org/logs/rubyci.s3.amazonaws.com/arch/ruby-master/log/20190804T000003Z.fail.html.gz
https://rubyci.org/logs/rubyci.s3.amazonaws.com/ubuntu1604/ruby-master/log/20190804T003005Z.fail.html.gz
https://rubyci.org/logs/rubyci.s3.amazonaws.com/icc-x64/ruby-master/log/20190804T000007Z.fail.html.gz
https://rubyci.org/logs/rubyci.s3.amazonaws.com/unstable10x/ruby-master/log/20190804T001806Z.fail.html.gz
https://rubyci.org/logs/rubyci.s3.amazonaws.com/debian9/ruby-master/log/20190804T003005Z.fail.html.gz

2 files changed, 4 insertions, 3 deletions

diff --git a/parse.y b/parse.y
index 3bff42ac56..de2a92285c 100644
--- a/parse.y
+++ b/parse.y
@@ -5812,7 +5812,7 @@ yycompile(VALUE vparser, struct parser_params *p, VALUE fname, int line)
 	p->ruby_sourcefile = "(none)";
     }
     else {
-	p->ruby_sourcefile_string = rb_str_new_frozen(fname);
+	p->ruby_sourcefile_string = rb_fstring(fname);
 	p->ruby_sourcefile = StringValueCStr(fname);
     }
     p->ruby_sourceline = line - 1;
@@ -9773,7 +9773,7 @@ gettable(struct parser_params *p, ID id, const YYLTYPE *loc)
 	    if (NIL_P(file))
 		file = rb_str_new(0, 0);
 	    else
-		file = rb_str_dup(rb_fstring(file));
+		file = rb_str_dup(file);
 	    node = NEW_STR(add_mark_object(p, file), loc);
 	}
 	return node;
diff --git a/vm_eval.c b/vm_eval.c
index eb728c0e7f..222389ec08 100644
--- a/vm_eval.c
+++ b/vm_eval.c
@@ -1284,6 +1284,7 @@ eval_make_iseq(VALUE src, VALUE fname, int line, const rb_binding_t *bind,
     }
 
     if (fname != Qundef) {
+        if (!NIL_P(fname)) fname = rb_fstring(fname);
 	realpath = fname;
     }
     else if (bind) {
@@ -1293,7 +1294,7 @@ eval_make_iseq(VALUE src, VALUE fname, int line, const rb_binding_t *bind,
 	rb_parser_warn_location(parser, TRUE);
     }
     else {
-        fname = rb_usascii_str_new_cstr("(eval)");
+        fname = rb_fstring_lit("(eval)");
     }
 
     rb_parser_set_context(parser, base_block, FALSE);