From ea3e7e268546599883b25d9a33d26e042461ac25 Mon Sep 17 00:00:00 2001 From: Aaron Patterson Date: Fri, 17 May 2019 17:08:31 +0300 Subject: [PATCH] Prevent Dynamic -> Static symbols from moving If a dynamic symbol has been converted to a static symbol, it gets added to the global ID list and should no longer move. C extensions can pass symbols to rb_sym2id and those symbols should no longer be movable. When the symbol is passed to rb_sym2id, the `id` member is set, so we can use its existence to prevent movement. --- gc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/gc.c b/gc.c index f344bb88b1..bf495bab4e 100644 --- a/gc.c +++ b/gc.c @@ -7256,6 +7256,10 @@ gc_is_moveable_obj(rb_objspace_t *objspace, VALUE obj) case T_ZOMBIE: return FALSE; break; + case T_SYMBOL: + if (DYNAMIC_SYM_P(obj) && (RSYMBOL(obj)->id & ~ID_SCOPE_MASK)) { + return FALSE; + } case T_STRING: case T_OBJECT: case T_FLOAT: @@ -7266,7 +7270,6 @@ gc_is_moveable_obj(rb_objspace_t *objspace, VALUE obj) case T_MODULE: case T_REGEXP: case T_DATA: - case T_SYMBOL: case T_MATCH: case T_STRUCT: case T_HASH: