Check type of instruction - can be INSN or ADJUST

If the type is ADJUST we don't want to treat it like an INSN so we have
to check the type before reading from `insn_info.events`.

[Bug #18001] [ruby-core:104371]

Co-authored-by: Aaron Patterson <[email protected]>

1 files changed, 1 insertions, 0 deletions

diff --git a/compile.c b/compile.c
index c541711ff9..a73a5be9a1 100644
--- a/compile.c
+++ b/compile.c
@@ -3088,6 +3088,7 @@ iseq_peephole_optimize(rb_iseq_t *iseq, LINK_ELEMENT *list, const int do_tailcal
          */
         int stop_optimization =
 	    ISEQ_COVERAGE(iseq) && ISEQ_LINE_COVERAGE(iseq) &&
+            nobj->link.type == ISEQ_ELEMENT_INSN &&
             nobj->insn_info.events;
 	if (!stop_optimization) {
             INSN *pobj = (INSN *)iobj->link.prev;