Revert "Fix dangling path name from fstring"

This reverts commit 5931857281ce45c1c277aa86d1588119ab00a955 temporarily,
leaving `TestEval#test_gced_eval_location` to see the impact for missing
the changes.

That's because too many CIs are failing for `require` behaviors:
http://rubyci.s3.amazonaws.com/freebsd11zfs/ruby-master/log/20190803T063004Z.fail.html.gz
http://rubyci.s3.amazonaws.com/unstable10x/ruby-master/log/20190803T051806Z.fail.html.gz
http://rubyci.s3.amazonaws.com/unstable11x/ruby-master/log/20190803T052406Z.fail.html.gz
http://rubyci.s3.amazonaws.com/unstable10s/ruby-master/log/20190803T111909Z.fail.html.gz
http://rubyci.s3.amazonaws.com/unstable11s/ruby-master/log/20190803T062506Z.fail.html.gz
http://rubyci.s3.amazonaws.com/solaris11s-sunc/ruby-master/log/20190803T052505Z.fail.html.gz
https://app.wercker.com/ruby/ruby/runs/mjit-test1/5d4512c921ca08000857936a?step=5d451305c2809c0008a3da76
https://app.wercker.com/ruby/ruby/runs/mjit-test2/5d4512c921ca080008579371?step=5d4513000421020007ca122d
http://ci.rvm.jp/results/trunk_gcc4@silicon-docker/2177591
http://ci.rvm.jp/results/trunk_gcc6@silicon-docker/2177596
http://ci.rvm.jp/results/trunk_clang_60@silicon-docker/2178802
http://ci.rvm.jp/results/trunk-theap-asserts@silicon-docker/2177555
http://ci.rvm.jp/results/trunk-mjit-wait@silicon-docker/2178747

Mostly `TestRequire#test_race_exception` failures, but in ci.rvm.jp
`require` inside rubyspec hangs very often.

1 files changed, 1 insertions, 2 deletions

diff --git a/vm_eval.c b/vm_eval.c
index 222389ec08..eb728c0e7f 100644
--- a/vm_eval.c
+++ b/vm_eval.c
@@ -1284,7 +1284,6 @@ 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) {
@@ -1294,7 +1293,7 @@ eval_make_iseq(VALUE src, VALUE fname, int line, const rb_binding_t *bind,
 	rb_parser_warn_location(parser, TRUE);
     }
     else {
-        fname = rb_fstring_lit("(eval)");
+        fname = rb_usascii_str_new_cstr("(eval)");
     }
 
     rb_parser_set_context(parser, base_block, FALSE);