Add some tests to verify that we implement LWG#2837 correctly. No functional change.
llvm-svn: 294194
diff --git a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.pass.cpp b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.pass.cpp
index af065b8..ddb14cd 100644
--- a/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.pass.cpp
+++ b/libcxx/test/std/numerics/numeric.ops/numeric.ops.gcd/gcd.pass.cpp
@@ -129,4 +129,11 @@
assert((do_test<long, int>(non_cce)));
assert((do_test<int, long long>(non_cce)));
assert((do_test<long long, int>(non_cce)));
+
+// LWG#2837
+ {
+ auto res = std::gcd((int64_t)1234, (int32_t)-2147483648);
+ static_assert( std::is_same<decltype(res), std::common_type<int64_t, int32_t>::type>::value, "");
+ assert(res == 2);
+ }
}