test: use libcxx template for main()

Author: PaulXiCao

libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/begin.pass.cpp

@@ -100,7 +100,8 @@ constexpr bool test() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test();
   static_assert(test());
+  return 0;
 }

libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/ctor.default.pass.cpp

@@ -62,7 +62,8 @@ constexpr bool test() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test();
   static_assert(test());
-}
+  return 0;
+}

libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/ctor.pass.cpp

@@ -30,7 +30,8 @@ constexpr bool test() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test();
   static_assert(test());
+  return 0;
 }

libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/ctor.views.pass.cpp

@@ -83,7 +83,8 @@ constexpr bool test() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test();
   static_assert(test());
-}
+  return 0;
+}

libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/example_from_std.pass.cpp

@@ -65,7 +65,8 @@ constexpr bool test() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test();
   static_assert(test());
-}
+  return 0;
+}

libcxx/test/std/ranges/range.adaptors/range.cartesian.product.view/size.pass.cpp

@@ -36,7 +36,8 @@ constexpr bool test() {
   return true;
 }
 
-int main() {
+int main(int, char**) {
   test();
   static_assert(test());
-}
+  return 0;
+}