[libc++] Mark some tests as unsupported on GCC 5

There used to be a workaround where we'd pretend that GCC 5 didn't support
C++14 because it doesn't implement it properly. Since that workaround has
been removed (in 1eb211ada1), we need to mark a few individual tests as
failing with GCC 5.

libcxx/test/libcxx/debug/containers/db_sequence_container_iterators.multithread.pass.cpp

@@ -9,6 +9,7 @@
 // UNSUPPORTED: c++03, c++11, c++14
 // UNSUPPORTED: windows
 // UNSUPPORTED: libcpp-has-no-threads
+// UNSUPPORTED: libcpp-no-if-constexpr
 // ADDITIONAL_COMPILE_FLAGS: -D_LIBCPP_DEBUG=1
 
 // Can't test the system lib because this test enables debug mode

libcxx/test/libcxx/diagnostics/nodiscard_extensions.pass.cpp

@@ -13,9 +13,10 @@
 // This test intentionally leaks memory, so it is unsupported under ASAN.
 // UNSUPPORTED: asan
 
-// AppleClang9 doesn't yet support C++17's implicitly synthesized deduction
-// guides from existing ctors, needed by default_searcher() below.
+// AppleClang9 and GCC 5 don't support C++17's implicitly synthesized
+// deduction guides from existing ctors, needed by default_searcher() below.
 // UNSUPPORTED: apple-clang-9
+// UNSUPPORTED: gcc-5
 
 // All entities to which libc++ applies [[nodiscard]] as an extension should
 // be tested here and in nodiscard_extensions.fail.cpp. They should also

libcxx/test/libcxx/double_include.sh.cpp

@@ -14,6 +14,11 @@
 // RUN: %{cxx} -o %t.exe %t.first.o %t.second.o %{flags} %{link_flags}
 // RUN: %{run}
 
+// GCC 5 pretends it supports C++17 features, but some features like static_assert
+// without a message are not actually supported. This causes some headers to fail
+// when included.
+// UNSUPPORTED: gcc-5 && c++17
+
 // Prevent <ext/hash_map> from generating deprecated warnings for this test.
 #if defined(__DEPRECATED)
 #undef __DEPRECATED

libcxx/test/libcxx/input.output/filesystems/convert_file_time.pass.cpp

@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++03, c++11
+// UNSUPPORTED: gcc-5
 
 // <filesystem>
 

libcxx/test/libcxx/memory/aligned_allocation_macro.pass.cpp

@@ -12,6 +12,9 @@
 // target, so this test would fail.
 // UNSUPPORTED: apple-clang-9, apple-clang-10
 
+// GCC 5 doesn't support aligned allocation
+// UNSUPPORTED: gcc-5
+
 // XFAIL: availability=macosx10.13
 // XFAIL: availability=macosx10.12
 // XFAIL: availability=macosx10.11

libcxx/test/libcxx/min_max_macros.compile.pass.cpp

@@ -10,6 +10,9 @@
 // Test that headers are not tripped up by the surrounding code defining the
 // min() and max() macros.
 
+// GCC 5 has incomplete support for C++17, so some headers fail when included.
+// UNSUPPORTED: gcc-5 && c++17
+
 // Prevent <ext/hash_map> from generating deprecated warnings for this test.
 #if defined(__DEPRECATED)
 #undef __DEPRECATED

libcxx/test/libcxx/no_assert_include.compile.pass.cpp

@@ -10,6 +10,9 @@
 // Ensure that none of the standard C++ headers implicitly include cassert or
 // assert.h (because assert() is implemented as a macro).
 
+// GCC 5 has incomplete support for C++17, so some headers fail when included.
+// UNSUPPORTED: gcc-5 && c++17
+
 // Prevent <ext/hash_map> from generating deprecated warnings for this test.
 #if defined(__DEPRECATED)
 #undef __DEPRECATED

libcxx/test/libcxx/utilities/optional/optional.object/optional.object.assign/copy.pass.cpp

@@ -7,6 +7,10 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++03, c++11, c++14
+
+// This test segfaults GCC 5
+// UNSUPPORTED: gcc-5
+
 // <optional>
 
 // optional<T>& operator=(const optional<T>& rhs);

libcxx/test/libcxx/utilities/optional/optional.object/optional.object.assign/move.pass.cpp

@@ -7,6 +7,10 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: c++03, c++11, c++14
+
+// This test segfaults GCC 5
+// UNSUPPORTED: gcc-5
+
 // <optional>
 
 // optional<T>& operator=(optional<T>&& rhs);

libcxx/test/libcxx/utilities/variant/variant.variant/variant_size.pass.cpp

@@ -9,6 +9,9 @@
 
 // UNSUPPORTED: c++03, c++11, c++14
 
+// GCC 5 pretends it supports C++17, but it doesn't properly support it
+// UNSUPPORTED: gcc-5
+
 // <variant>
 
 // template <class ...Types> class variant;

libcxx/test/libcxx/utilities/variant/version.pass.cpp

@@ -8,6 +8,10 @@
 
 // <variant>
 
+// GCC 5 pretends it supports C++17, but it doesn't properly support it, and
+// <variant> fails.
+// UNSUPPORTED: gcc-5
+
 #include <variant>
 
 #include "test_macros.h"

libcxx/test/std/algorithms/alg.modifying.operations/alg.random.sample/sample.fail.cpp

@@ -8,6 +8,9 @@
 
 // UNSUPPORTED: c++03, c++11, c++14
 
+// Test failure not investigated on GCC 5.
+// UNSUPPORTED: gcc-5
+
 // <algorithm>
 
 // template <class PopulationIterator, class SampleIterator, class Distance,

libcxx/test/std/containers/sequences/array/aggregate.pass.cpp

@@ -11,6 +11,10 @@
 // trait before that.
 // UNSUPPORTED: c++03, c++11, c++14
 
+// libc++ doesn't implement std::is_aggregate on GCC 5 and GCC 6.
+// UNSUPPORTED: libc++ && gcc-5
+// UNSUPPORTED: libc++ && gcc-6
+
 #include <array>
 #include <type_traits>
 

libcxx/test/std/containers/sequences/array/at.pass.cpp

@@ -10,6 +10,9 @@
 
 // reference at (size_type); // constexpr in C++17
 
+// GCC 5 doesn't implement the required constexpr support
+// UNSUPPORTED: gcc-5
+
 #include <array>
 #include <cassert>
 

libcxx/test/std/containers/sequences/array/at_const.pass.cpp

@@ -10,6 +10,9 @@
 
 // const_reference at (size_type) const; // constexpr in C++14
 
+// GCC 5 doesn't implement the required constexpr support
+// UNSUPPORTED: gcc-5
+
 #include <array>
 #include <cassert>
 

libcxx/test/std/containers/sequences/array/contiguous.pass.cpp

@@ -8,6 +8,9 @@
 
 // <array>
 
+// GCC 5 doesn't implement the required constexpr support
+// UNSUPPORTED: gcc-5
+
 // An array is a contiguous container
 
 #include <array>

libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.nonmember/make_move_iterator.pass.cpp

@@ -50,7 +50,7 @@ int main(int, char**)
     {
     constexpr const char *p = "123456789";
     constexpr auto iter = std::make_move_iterator<const char *>(p);
-    static_assert(iter.base() == p);
+    static_assert(iter.base() == p, "");
     }
 #endif
 

libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_gt.pass.cpp

@@ -17,6 +17,9 @@
 //
 //  constexpr in C++17
 
+// GCC 5 doesn't implement the required constexpr support
+// UNSUPPORTED: gcc-5
+
 #include <iterator>
 #include <cassert>
 

libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_gte.pass.cpp

@@ -17,6 +17,9 @@
 //
 //  constexpr in C++17
 
+// GCC 5 doesn't implement the required constexpr support
+// UNSUPPORTED: gcc-5
+
 #include <iterator>
 #include <cassert>
 

libcxx/test/std/iterators/predef.iterators/move.iterators/move.iter.ops/move.iter.op.comp/op_lte.pass.cpp

@@ -17,6 +17,9 @@
 //
 //  constexpr in C++17
 
+// GCC 5 doesn't implement the required constexpr support
+// UNSUPPORTED: gcc-5
+
 #include <iterator>
 #include <cassert>