diff --git a/libcxx/test/libcxx/diagnostics/nodiscard_extensions.compile.pass.cpp b/libcxx/test/libcxx/diagnostics/nodiscard_extensions.compile.pass.cpp
--- a/libcxx/test/libcxx/diagnostics/nodiscard_extensions.compile.pass.cpp
+++ b/libcxx/test/libcxx/diagnostics/nodiscard_extensions.compile.pass.cpp
@@ -183,12 +183,10 @@
 #endif
 }
 
-int main(int, char**) {
+void tests() {
   test_algorithms();
 
   int i = 42;
   test_template_cast_wrappers(i, std::move(i));
   test_nontemplate_cast_wrappers();
-
-  return 0;
 }
diff --git a/libcxx/test/libcxx/ranges/version.compile.pass.cpp b/libcxx/test/libcxx/ranges/version.compile.pass.cpp
--- a/libcxx/test/libcxx/ranges/version.compile.pass.cpp
+++ b/libcxx/test/libcxx/ranges/version.compile.pass.cpp
@@ -16,6 +16,3 @@
 #ifndef _LIBCPP_VERSION
 #error _LIBCPP_VERSION not defined
 #endif
-
-// Required for MSVC internal test runner compatibility.
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/libcxx/thread/thread.barrier/version.compile.pass.cpp b/libcxx/test/libcxx/thread/thread.barrier/version.compile.pass.cpp
--- a/libcxx/test/libcxx/thread/thread.barrier/version.compile.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.barrier/version.compile.pass.cpp
@@ -18,8 +18,3 @@
 #ifndef _LIBCPP_VERSION
 #error _LIBCPP_VERSION not defined
 #endif
-
-int main(int, char**)
-{
-  return 0;
-}
diff --git a/libcxx/test/libcxx/thread/thread.latch/version.compile.pass.cpp b/libcxx/test/libcxx/thread/thread.latch/version.compile.pass.cpp
--- a/libcxx/test/libcxx/thread/thread.latch/version.compile.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.latch/version.compile.pass.cpp
@@ -18,8 +18,3 @@
 #ifndef _LIBCPP_VERSION
 #error _LIBCPP_VERSION not defined
 #endif
-
-int main(int, char**)
-{
-  return 0;
-}
diff --git a/libcxx/test/libcxx/thread/thread.semaphore/version.compile.pass.cpp b/libcxx/test/libcxx/thread/thread.semaphore/version.compile.pass.cpp
--- a/libcxx/test/libcxx/thread/thread.semaphore/version.compile.pass.cpp
+++ b/libcxx/test/libcxx/thread/thread.semaphore/version.compile.pass.cpp
@@ -18,8 +18,3 @@
 #ifndef _LIBCPP_VERSION
 #error _LIBCPP_VERSION not defined
 #endif
-
-int main(int, char**)
-{
-  return 0;
-}
diff --git a/libcxx/test/libcxx/utilities/format/version.compile.pass.cpp b/libcxx/test/libcxx/utilities/format/version.compile.pass.cpp
--- a/libcxx/test/libcxx/utilities/format/version.compile.pass.cpp
+++ b/libcxx/test/libcxx/utilities/format/version.compile.pass.cpp
@@ -17,6 +17,3 @@
 #ifndef _LIBCPP_VERSION
 #  error _LIBCPP_VERSION not defined
 #endif
-
-// Required for MSVC internal test runner compatibility.
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/atomics/atomics.types.generic/standard_layout.compile.pass.cpp b/libcxx/test/std/atomics/atomics.types.generic/standard_layout.compile.pass.cpp
--- a/libcxx/test/std/atomics/atomics.types.generic/standard_layout.compile.pass.cpp
+++ b/libcxx/test/std/atomics/atomics.types.generic/standard_layout.compile.pass.cpp
@@ -25,10 +25,8 @@
   }
 };
 
-int main(int, char**) {
+void tests() {
   TestEachIntegralType<CheckStandardLayout>()();
   TestEachFloatingPointType<CheckStandardLayout>()();
   TestEachPointerType<CheckStandardLayout>()();
-
-  return 0;
 }
diff --git a/libcxx/test/std/concepts/concepts.compare/concept.equalitycomparable/equality_comparable.compile.pass.cpp b/libcxx/test/std/concepts/concepts.compare/concept.equalitycomparable/equality_comparable.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.compare/concept.equalitycomparable/equality_comparable.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.compare/concept.equalitycomparable/equality_comparable.compile.pass.cpp
@@ -141,5 +141,3 @@
 static_assert(std::equality_comparable<returns_true_type>);
 static_assert(std::equality_comparable<returns_int_ptr>);
 } // namespace types_fit_for_purpose
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.compare/concept.equalitycomparable/equality_comparable_with.compile.pass.cpp b/libcxx/test/std/concepts/concepts.compare/concept.equalitycomparable/equality_comparable_with.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.compare/concept.equalitycomparable/equality_comparable_with.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.compare/concept.equalitycomparable/equality_comparable_with.compile.pass.cpp
@@ -1120,5 +1120,3 @@
 static_assert(
     !check_equality_comparable_with<one_way_ne, explicit_operators>());
 } // namespace types_fit_for_purpose
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.lang/concept.common/common_with.compile.pass.cpp b/libcxx/test/std/concepts/concepts.lang/concept.common/common_with.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.lang/concept.common/common_with.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.lang/concept.common/common_with.compile.pass.cpp
@@ -990,5 +990,3 @@
     : common_type<CommonWithIntButRefLong&, int&> {};
 } // namespace std
 static_assert(CheckCommonWith<CommonWithIntButRefLong, int>());
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.lang/concept.commonref/common_reference.compile.pass.cpp b/libcxx/test/std/concepts/concepts.lang/concept.commonref/common_reference.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.lang/concept.commonref/common_reference.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.lang/concept.commonref/common_reference.compile.pass.cpp
@@ -343,5 +343,3 @@
 } // namespace std
 static_assert(!std::common_reference_with<HasCommonReference, int>);
 static_assert(std::common_reference_with<HasCommonReference, int&>);
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.lang/concept.constructible/constructible_from.compile.pass.cpp b/libcxx/test/std/concepts/concepts.lang/concept.constructible/constructible_from.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.lang/concept.constructible/constructible_from.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.lang/concept.constructible/constructible_from.compile.pass.cpp
@@ -148,5 +148,3 @@
   test<std::array<int, 1>, int>();
   test<std::array<int, 1>, int, int>();
 }
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.lang/concept.copyconstructible/copy_constructible.compile.pass.cpp b/libcxx/test/std/concepts/concepts.lang/concept.copyconstructible/copy_constructible.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.lang/concept.copyconstructible/copy_constructible.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.lang/concept.copyconstructible/copy_constructible.compile.pass.cpp
@@ -172,5 +172,3 @@
 };
 static_assert(!std::copy_constructible<ExplicitlyCopyable>);
 } // namespace CopyConstructibleTests
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.lang/concept.default.init/default_initializable.compile.pass.cpp b/libcxx/test/std/concepts/concepts.lang/concept.default.init/default_initializable.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.lang/concept.default.init/default_initializable.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.lang/concept.default.init/default_initializable.compile.pass.cpp
@@ -261,8 +261,3 @@
     test_true     <std::weak_ptr<int>>();
 
 }
-
-// Required for MSVC internal test runner compatibility.
-int main(int, char**) {
-    return 0;
-}
diff --git a/libcxx/test/std/concepts/concepts.lang/concept.destructible/destructible.compile.pass.cpp b/libcxx/test/std/concepts/concepts.lang/concept.destructible/destructible.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.lang/concept.destructible/destructible.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.lang/concept.destructible/destructible.compile.pass.cpp
@@ -73,6 +73,3 @@
   test<int>();
   test<double>();
 }
-
-// Required for MSVC internal test runner compatibility.
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.lang/concept.moveconstructible/move_constructible.compile.pass.cpp b/libcxx/test/std/concepts/concepts.lang/concept.moveconstructible/move_constructible.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.lang/concept.moveconstructible/move_constructible.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.lang/concept.moveconstructible/move_constructible.compile.pass.cpp
@@ -76,5 +76,3 @@
 static_assert(!std::move_constructible<NonMovable>);
 static_assert(!std::move_constructible<DerivedFromNonMovable>);
 static_assert(!std::move_constructible<HasANonMovable>);
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.object/copyable.compile.pass.cpp b/libcxx/test/std/concepts/concepts.object/copyable.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.object/copyable.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.object/copyable.compile.pass.cpp
@@ -113,5 +113,3 @@
     !std::assignable_from<deleted_assignment_from_const_rvalue&,
                           deleted_assignment_from_const_rvalue const>);
 static_assert(!std::copyable<deleted_assignment_from_const_rvalue>);
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.object/movable.compile.pass.cpp b/libcxx/test/std/concepts/concepts.object/movable.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.object/movable.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.object/movable.compile.pass.cpp
@@ -133,5 +133,3 @@
 
 // `move_constructible and assignable_from<T&, T>` implies `swappable<T>`,
 // so there's nothing to test for the case of non-swappable.
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.object/regular.compile.pass.cpp b/libcxx/test/std/concepts/concepts.object/regular.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.object/regular.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.object/regular.compile.pass.cpp
@@ -163,5 +163,3 @@
   bool operator==(is_equality_comparable const&) const = default;
 };
 static_assert(std::regular<is_equality_comparable>);
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/concepts/concepts.object/semiregular.compile.pass.cpp b/libcxx/test/std/concepts/concepts.object/semiregular.compile.pass.cpp
--- a/libcxx/test/std/concepts/concepts.object/semiregular.compile.pass.cpp
+++ b/libcxx/test/std/concepts/concepts.object/semiregular.compile.pass.cpp
@@ -126,5 +126,3 @@
 static_assert(!std::semiregular<deleted_default_ctor>);
 static_assert(!std::semiregular<derived_from_deleted_default_ctor>);
 static_assert(!std::semiregular<has_deleted_default_ctor>);
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/numerics/rand/rand.req/rand.req.urng/uniform_random_bit_generator.compile.pass.cpp b/libcxx/test/std/numerics/rand/rand.req/rand.req.urng/uniform_random_bit_generator.compile.pass.cpp
--- a/libcxx/test/std/numerics/rand/rand.req/rand.req.urng/uniform_random_bit_generator.compile.pass.cpp
+++ b/libcxx/test/std/numerics/rand/rand.req/rand.req.urng/uniform_random_bit_generator.compile.pass.cpp
@@ -140,5 +140,3 @@
   static constexpr unsigned char max() { return 1; }
 };
 static_assert(std::uniform_random_bit_generator<Works>);
-
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/utilities/format/format.arguments/format.args/types.compile.pass.cpp b/libcxx/test/std/utilities/format/format.arguments/format.args/types.compile.pass.cpp
--- a/libcxx/test/std/utilities/format/format.arguments/format.args/types.compile.pass.cpp
+++ b/libcxx/test/std/utilities/format/format.arguments/format.args/types.compile.pass.cpp
@@ -26,6 +26,3 @@
 static_assert(std::is_same_v<std::wformat_args,
                              std::basic_format_args<std::wformat_context>>);
 #endif
-
-// Required for MSVC internal test runner compatibility.
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/utilities/format/format.formatter/format.parse.ctx/types.compile.pass.cpp b/libcxx/test/std/utilities/format/format.formatter/format.parse.ctx/types.compile.pass.cpp
--- a/libcxx/test/std/utilities/format/format.formatter/format.parse.ctx/types.compile.pass.cpp
+++ b/libcxx/test/std/utilities/format/format.formatter/format.parse.ctx/types.compile.pass.cpp
@@ -62,6 +62,3 @@
 static_assert(std::is_same_v<std::wformat_parse_context,
                              std::basic_format_parse_context<wchar_t> >);
 #endif
-
-// Required for MSVC internal test runner compatibility.
-int main(int, char**) { return 0; }
diff --git a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/common_reference.compile.pass.cpp b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/common_reference.compile.pass.cpp
--- a/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/common_reference.compile.pass.cpp
+++ b/libcxx/test/std/utilities/meta/meta.trans/meta.trans.other/common_reference.compile.pass.cpp
@@ -217,5 +217,3 @@
 static_assert(!has_type<std::common_reference<std::pair<int, X2>, std::pair<float, Z2>>>);
 static_assert(!has_type<std::common_reference<std::pair<int, X2>, int, X2>>);
 #endif
-
-int main(int, char**) { return 0; }