diff --git a/src/cmd/internal/obj/pcln.go b/src/cmd/internal/obj/pcln.go
index 1f7ccf47ef..bffeda041d 100644
--- a/src/cmd/internal/obj/pcln.go
+++ b/src/cmd/internal/obj/pcln.go
@@ -278,6 +278,21 @@ func linkpcln(ctxt *Link, cursym *LSym) {
 	funcpctab(ctxt, &pcln.Pcfile, cursym, "pctofile", pctofileline, pcln)
 	funcpctab(ctxt, &pcln.Pcline, cursym, "pctoline", pctofileline, nil)
 
+	// Check that all the Progs used as inline markers are still reachable.
+	// See issue #40473.
+	inlMarkProgs := make(map[*Prog]struct{}, len(cursym.Func.InlMarks))
+	for _, inlMark := range cursym.Func.InlMarks {
+		inlMarkProgs[inlMark.p] = struct{}{}
+	}
+	for p := cursym.Func.Text; p != nil; p = p.Link {
+		if _, ok := inlMarkProgs[p]; ok {
+			delete(inlMarkProgs, p)
+		}
+	}
+	if len(inlMarkProgs) > 0 {
+		ctxt.Diag("one or more instructions used as inline markers are no longer reachable")
+	}
+
 	pcinlineState := new(pcinlineState)
 	funcpctab(ctxt, &pcln.Pcinline, cursym, "pctoinline", pcinlineState.pctoinline, nil)
 	for _, inlMark := range cursym.Func.InlMarks {
diff --git a/src/cmd/internal/obj/s390x/objz.go b/src/cmd/internal/obj/s390x/objz.go
index b14dc810fa..ef6335d849 100644
--- a/src/cmd/internal/obj/s390x/objz.go
+++ b/src/cmd/internal/obj/s390x/objz.go
@@ -283,17 +283,6 @@ func preprocess(ctxt *obj.Link, cursym *obj.LSym, newprog obj.ProgAlloc) {
 			ACMPUBNE:
 			q = p
 			p.Mark |= BRANCH
-			if p.Pcond != nil {
-				q := p.Pcond
-				for q.As == obj.ANOP {
-					q = q.Link
-					p.Pcond = q
-				}
-			}
-
-		case obj.ANOP:
-			q.Link = p.Link /* q is non-nop */
-			p.Link.Mark |= p.Mark
 
 		default:
 			q = p