diff --git a/internal/vm.h b/internal/vm.h
index d1ee437cdc..3ee958a020 100644
--- a/internal/vm.h
+++ b/internal/vm.h
@@ -121,7 +121,6 @@ int rb_get_node_id_from_frame_info(VALUE obj);
 const struct rb_iseq_struct *rb_get_iseq_from_frame_info(VALUE obj);
 
 VALUE rb_ec_backtrace_object(const struct rb_execution_context_struct *ec);
-void rb_backtrace_use_iseq_first_lineno_for_last_location(VALUE self);
 
 #define RUBY_DTRACE_CREATE_HOOK(name, arg) \
     RUBY_DTRACE_HOOK(name##_CREATE, arg)
diff --git a/vm_args.c b/vm_args.c
index 4738eda72c..233ade69c6 100644
--- a/vm_args.c
+++ b/vm_args.c
@@ -985,7 +985,6 @@ raise_argument_error(rb_execution_context_t *ec, const rb_iseq_t *iseq, const VA
                       ISEQ_BODY(iseq)->iseq_encoded,
                       ec->cfp->sp, 0, 0 /* stack_max */);
         at = rb_ec_backtrace_object(ec);
-        rb_backtrace_use_iseq_first_lineno_for_last_location(at);
         rb_vm_pop_frame(ec);
     }
     else {
diff --git a/vm_backtrace.c b/vm_backtrace.c
index 68fc2b987b..ef57f4c403 100644
--- a/vm_backtrace.c
+++ b/vm_backtrace.c
@@ -715,7 +715,12 @@ rb_ec_partial_backtrace_object(const rb_execution_context_t *ec, long start_fram
                         }
                         else {
                             RB_OBJ_WRITE(btobj, &loc->iseq, iseq);
-                            loc->pc = pc;
+                            if ((VM_FRAME_TYPE(cfp) & VM_FRAME_MAGIC_MASK) == VM_FRAME_MAGIC_DUMMY) {
+                                loc->pc = NULL; // means location.first_lineno
+                            }
+                            else {
+                                loc->pc = pc;
+                            }
                             bt_backpatch_loc(backpatch_counter, loc-1, iseq, pc);
                             if (do_yield) {
                                 bt_yield_loc(loc - backpatch_counter, backpatch_counter+1, btobj);
@@ -813,22 +818,6 @@ rb_backtrace_to_str_ary(VALUE self)
     return bt->strary;
 }
 
-void
-rb_backtrace_use_iseq_first_lineno_for_last_location(VALUE self)
-{
-    rb_backtrace_t *bt;
-    rb_backtrace_location_t *loc;
-
-    TypedData_Get_Struct(self, rb_backtrace_t, &backtrace_data_type, bt);
-    VM_ASSERT(bt->backtrace_size > 0);
-
-    loc = &bt->backtrace[0];
-
-    VM_ASSERT(!loc->cme || loc->cme->def->type == VM_METHOD_TYPE_ISEQ);
-
-    loc->pc = NULL; // means location.first_lineno
-}
-
 static VALUE
 location_create(rb_backtrace_location_t *srcloc, void *btobj)
 {