diff --git a/src/cmd/compile/internal/gc/const.go b/src/cmd/compile/internal/gc/const.go
index d30515a87b..795b53da11 100644
--- a/src/cmd/compile/internal/gc/const.go
+++ b/src/cmd/compile/internal/gc/const.go
@@ -634,6 +634,7 @@ func evconst(n *Node) {
 	var wr int
 	var v Val
 	var norig *Node
+	var nn *Node
 	if nr == nil {
 		// copy numeric value to avoid modifying
 		// nl, in case someone still refers to it (e.g. iota).
@@ -1115,15 +1116,21 @@ ret:
 	return
 
 settrue:
-	norig = saveorig(n)
-	*n = *Nodbool(true)
-	n.Orig = norig
+	nn = Nodbool(true)
+	nn.Orig = saveorig(n)
+	if !iscmp[n.Op] {
+		nn.Type = nl.Type
+	}
+	*n = *nn
 	return
 
 setfalse:
-	norig = saveorig(n)
-	*n = *Nodbool(false)
-	n.Orig = norig
+	nn = Nodbool(false)
+	nn.Orig = saveorig(n)
+	if !iscmp[n.Op] {
+		nn.Type = nl.Type
+	}
+	*n = *nn
 	return
 
 illegal:
diff --git a/src/cmd/compile/internal/gc/typecheck.go b/src/cmd/compile/internal/gc/typecheck.go
index 224480279c..8c1305f7f4 100644
--- a/src/cmd/compile/internal/gc/typecheck.go
+++ b/src/cmd/compile/internal/gc/typecheck.go
@@ -687,8 +687,6 @@ OpSwitch:
 				n.Left = l
 				n.Right = r
 			}
-		} else if n.Op == OANDAND || n.Op == OOROR {
-			evconst(n)
 		}
 
 		if et == TSTRING {
diff --git a/test/fixedbugs/issue13821b.go b/test/fixedbugs/issue13821b.go
index 3b0e2d2287..0950fdea96 100644
--- a/test/fixedbugs/issue13821b.go
+++ b/test/fixedbugs/issue13821b.go
@@ -20,3 +20,5 @@ var x4 = x1 && b2   // ERROR "mismatched types B and B2"
 var x5 = x2 && b2   // ERROR "mismatched types B and B2"
 var x6 = b2 && x1   // ERROR "mismatched types B2 and B"
 var x7 = b2 && x2   // ERROR "mismatched types B2 and B"
+
+var x8 = b && !B2(true) // ERROR "mismatched types B and B2"