Fix a consistency bug of ISEQ_COVERAGE [Bug #13305]

There is an invariant that ISEQ_COVERAGE(iseq) must be Qnil if and only
if option->coverage_enabled is false.  This invariant was broken by
NODE_PRELUDE which updates option->coverage_enabled but not
ISEQ_COVERAGE(iseq).

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57971 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 4 insertions, 1 deletions

diff --git a/compile.c b/compile.c
index f6d8964fbb..7bfca53055 100644
--- a/compile.c
+++ b/compile.c
@@ -6310,14 +6310,17 @@ iseq_compile_each0(rb_iseq_t *iseq, LINK_ANCHOR *const ret, NODE *node, int popp
       }
       case NODE_PRELUDE:{
 	const rb_compile_option_t *orig_opt = ISEQ_COMPILE_DATA(iseq)->option;
+	VALUE orig_cov = ISEQ_COVERAGE(iseq);
+	rb_compile_option_t new_opt = *orig_opt;
 	if (node->nd_orig) {
-	    rb_compile_option_t new_opt = *orig_opt;
 	    rb_iseq_make_compile_option(&new_opt, node->nd_orig);
 	    ISEQ_COMPILE_DATA(iseq)->option = &new_opt;
 	}
+	if (!new_opt.coverage_enabled) ISEQ_COVERAGE_SET(iseq, Qfalse);
 	CHECK(COMPILE_POPPED(ret, "prelude", node->nd_head));
 	CHECK(COMPILE_(ret, "body", node->nd_body, popped));
 	ISEQ_COMPILE_DATA(iseq)->option = orig_opt;
+	ISEQ_COVERAGE_SET(iseq, orig_cov);
 	break;
       }
       case NODE_LAMBDA:{