diff --git a/src/cmd/compile/internal/gc/plive.go b/src/cmd/compile/internal/gc/plive.go
index 88b43806370..f78d051b060 100644
--- a/src/cmd/compile/internal/gc/plive.go
+++ b/src/cmd/compile/internal/gc/plive.go
@@ -692,6 +692,11 @@ func (lv *Liveness) markUnsafePoints() {
 			lv.f.Fatalf("expected branch at write barrier block %v", wbBlock)
 		}
 		s0, s1 := wbBlock.Succs[0].Block(), wbBlock.Succs[1].Block()
+		if s0 == s1 {
+			// There's no difference between write barrier on and off.
+			// Thus there's no unsafe locations. See issue 26024.
+			continue
+		}
 		if s0.Kind != ssa.BlockPlain || s1.Kind != ssa.BlockPlain {
 			lv.f.Fatalf("expected successors of write barrier block %v to be plain", wbBlock)
 		}
diff --git a/test/fixedbugs/issue26024.go b/test/fixedbugs/issue26024.go
new file mode 100644
index 00000000000..78877b21fe5
--- /dev/null
+++ b/test/fixedbugs/issue26024.go
@@ -0,0 +1,28 @@
+// compile
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package r
+
+// f compiles into code where no stores remain in the two successors
+// of a write barrier block; i.e., they are empty. Pre-fix, this
+// results in an unexpected input to markUnsafePoints, that expects to
+// see a pair of non-empty plain blocks.
+func f() {
+	var i int
+	var s string
+	for len(s) < len(s) {
+		i++
+		s = "a"
+	}
+	var b bool
+	var sa []string
+	for true {
+		sa = []string{""}
+		for b || i == 0 {
+		}
+		b = !b
+		_ = sa
+	}
+}