[libcxx-commits] [libcxx] [libc++] std::abs support for _BitInt(N) and __int128 (PR #196532)

[A. Jiang via libcxx-commits]

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@@ -37,6 +37,68 @@ void test_big() {
   assert(std::abs(negative_big_value) == big_value); // make sure it doesn't get casted to a smaller type
 }
 
+// std::abs has __int128/_BitInt(N) overloads as a libc++ extension. The
+// decltype-SFINAE probes below need C++11.
+#if TEST_STD_VER >= 11
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frederick-vs-ja wrote:

I think we can enable the test coverage in C++03 mode, as libc++ backports `decltype` to C++03.

https://github.com/llvm/llvm-project/blob/a6fe3c7422db83346c336346e0b7a56ff084b17f/libcxx/include/__config#L164

We may need to skip coverage for frozen C++03 headers (by `// XFAIL: FROZEN-CXX03-HEADERS-FIXME`), though.

https://github.com/llvm/llvm-project/pull/196532