rb_enc_interned_str: handle autoloaded encodings

If called with an autoloaded encoding that was not yet
initialized, `rb_enc_interned_str` would crash with
a NULL pointer exception.

See: https://github.com/ruby/ruby/pull/4119#issuecomment-800189841

1 files changed, 3 insertions, 0 deletions

diff --git a/internal/encoding.h b/internal/encoding.h
index af236daeaf..c0cf061bd4 100644
--- a/internal/encoding.h
+++ b/internal/encoding.h
@@ -12,12 +12,15 @@
 #include "ruby/ruby.h"          /* for ID */
 #include "ruby/encoding.h"      /* for rb_encoding */
 
+#define rb_enc_autoload_p(enc) (!rb_enc_mbmaxlen(enc))
+
 /* encoding.c */
 ID rb_id_encoding(void);
 rb_encoding *rb_enc_get_from_index(int index);
 rb_encoding *rb_enc_check_str(VALUE str1, VALUE str2);
 int rb_encdb_replicate(const char *alias, const char *orig);
 int rb_encdb_alias(const char *alias, const char *orig);
+int rb_enc_autoload(rb_encoding *enc);
 int rb_encdb_dummy(const char *name);
 void rb_encdb_declare(const char *name);
 void rb_enc_set_base(const char *name, const char *orig);