string.c: clear env self in symbol proc

* string.c (sym_to_proc), proc.c (rb_block_clear_env_self): clear
  caller's self which is useless, so that it can get collected.
  [Fixes GH-592]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@45576 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 0 deletions

diff --git a/string.c b/string.c
index 56b27d9d75..28b1efa2e9 100644
--- a/string.c
+++ b/string.c
@@ -8506,6 +8506,7 @@ sym_to_proc(VALUE sym)
     }
     else {
 	proc = rb_proc_new(sym_call, (VALUE)id);
+	rb_block_clear_env_self(proc);
 	aryp[index] = sym;
 	aryp[index + 1] = proc;
 	return proc;