--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/cpp2a/explicit1.C	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,63 @@
+// P0892R2
+// { dg-do compile }
+// { dg-options "-std=c++2a" }
+
+constexpr int fn0 () { return 0; }
+constexpr int fn1 () { return 1; }
+
+struct S {
+  explicit(true) S(int);
+  explicit(1 == 0) S(int, int);
+  explicit(fn0()) S(int, int, int);
+  explicit(fn1()) S(int, int, int, int);
+};
+
+struct X {
+  static const bool value = true;
+  static constexpr bool foo () { return 1; }
+};
+
+struct T {
+  explicit(true ? 1 : throw 1) T(int);
+  explicit(true || true ? 1 : throw 1) T(int, int);
+  explicit(X::value) T(int, int, int);
+  explicit(X::foo ()) T(int, int, int, int);
+};
+
+struct W {
+  constexpr operator bool() { return true; };
+};
+
+struct W2 {
+  constexpr operator bool() { return false; };
+};
+
+struct U {
+  explicit(W()) U(int);
+  explicit(W2()) U(int, int);
+};
+
+int
+main ()
+{
+  S s1 = { 1 }; // { dg-error "converting" }
+  S s1x{ 1 };
+  S s2 = { 2, 3 };
+  S s3 = { 4, 5, 6 };
+  S s4 = { 7, 8, 9, 10 }; // { dg-error "converting" }
+  S s4x{ 7, 8, 9, 10 };
+
+  T t1 = { 1 }; // { dg-error "converting" }
+  T t2 = { 1, 2 }; // { dg-error "converting" }
+  T t3 = { 1, 2, 3 }; // { dg-error "converting" }
+  T t4 = { 1, 2, 3, 4 }; // { dg-error "converting" }
+  T t5{ 1 };
+  T t6{ 1, 2 };
+  T t7{ 1, 2, 3 };
+  T t8{ 1, 2, 3, 4 };
+
+  U u1 = { 1 }; // { dg-error "converting" }
+  U u2{ 1 };
+  U u3 = { 1, 2 };
+  U u4 { 1, 2 };
+}