Clean up a bunch of warnings in the tests, 3 of which actually turned out to be test bugs.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@131479 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/utilities/template.bitset/bitset.members/count.pass.cpp b/test/utilities/template.bitset/bitset.members/count.pass.cpp
index 1781e9b..fb9ce64 100644
--- a/test/utilities/template.bitset/bitset.members/count.pass.cpp
+++ b/test/utilities/template.bitset/bitset.members/count.pass.cpp
@@ -13,6 +13,8 @@
 #include <cstdlib>
 #include <cassert>
 
+#pragma clang diagnostic ignored "-Wtautological-compare"
+
 template <std::size_t N>
 std::bitset<N>
 make_bitset()