diff --git a/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign2.pass.cpp b/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign2.pass.cpp
index c669ab9c1..9ff50323a 100644
--- a/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign2.pass.cpp
+++ b/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/assign2.pass.cpp
@@ -32,6 +32,7 @@ int main(int, char**)
     assert(c == u8'a');
 
     static_assert(test_constexpr(), "");
+    return 0;
 }
 #else
 int main(int, char**) {
diff --git a/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/compare.pass.cpp b/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/compare.pass.cpp
index 063ab5dc5..be2462927 100644
--- a/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/compare.pass.cpp
+++ b/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/compare.pass.cpp
@@ -51,6 +51,7 @@ int main(int, char**)
     assert(std::char_traits<char8_t>::compare(u8"124", u8"123", 3) > 0);
 
     static_assert(test_constexpr(), "" );
+    return 0;
 }
 #else
 int main(int, char**) {
diff --git a/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/find.pass.cpp b/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/find.pass.cpp
index 170539e06..32e17af23 100644
--- a/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/find.pass.cpp
+++ b/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/find.pass.cpp
@@ -39,6 +39,7 @@ int main(int, char**)
     assert(std::char_traits<char8_t>::find(NULL, 0, char8_t(0)) == 0);
 
     static_assert(test_constexpr(), "" );
+    return 0;
 }
 #else
 int main(int, char**) {
diff --git a/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/length.pass.cpp b/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/length.pass.cpp
index ce2c717cc..419366cd1 100644
--- a/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/length.pass.cpp
+++ b/test/std/strings/char.traits/char.traits.specializations/char.traits.specializations.char8_t/length.pass.cpp
@@ -34,6 +34,7 @@ int main(int, char**)
     assert(std::char_traits<char8_t>::length(u8"aaaa") == 4);
 
     static_assert(test_constexpr(), "");
+    return 0;
 }
 #else
 int main(int, char**) {