[libc++][test] std::variant test cleanup

* Add the conventional `return 0` to `main` in `variant.assign/conv.pass.cpp` and `variant.ctor/conv.pass.cpp`

* Fix some MSVC signed-to-unsigned conversion warnings by replacing `int` literarls with `unsigned int` literals

llvm-svn: 374723

1 files changed, 1 insertions, 1 deletions

diff --git a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
index 820d81e71e6..07ca63f2363 100644
--- a/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
+++ b/libcxx/test/std/utilities/variant/variant.variant/variant.assign/copy.pass.cpp
@@ -453,7 +453,7 @@ void test_copy_assignment_different_index() {
   {
     using V = std::variant<int, CopyAssign, unsigned>;
     CopyAssign::reset();
-    V v1(std::in_place_type<unsigned>, 43);
+    V v1(std::in_place_type<unsigned>, 43u);
     V v2(std::in_place_type<CopyAssign>, 42);
     assert(CopyAssign::copy_construct == 0);
     assert(CopyAssign::move_construct == 0);