[libc++] Split off tests for aligned_alloc & friends into separate test files

This allows testing the rest of those headers on most platforms, instead
of XFAILing the whole test just because of a few functions.

As a fly-by fix, remove std/utilities/time/date.time/ctime.pass.cpp,
which was a duplicate of std/language.support/support.runtime/ctime.pass.cpp.

Differential Revision: https://reviews.llvm.org/D108295

Author: ldionne

libcxx/test/std/depr/depr.c.headers/stdlib_h.aligned_alloc.compile.pass.cpp

@@ -0,0 +1,24 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// test <stdlib.h>
+// ::aligned_alloc
+
+// UNSUPPORTED: c++03, c++11, c++14
+
+// ::aligned_alloc is provided by the C library, but it's marked as unavailable
+// until macOS 10.15
+// XFAIL: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}}
+
+// ::aligned_alloc is not implemented on Windows
+// XFAIL: target={{.+}}-pc-windows-{{.+}}
+
+#include <stdlib.h>
+#include <type_traits>
+
+static_assert(std::is_same<decltype(aligned_alloc(1, 0)), void*>::value, "");

libcxx/test/std/depr/depr.c.headers/stdlib_h.pass.cpp

@@ -8,13 +8,6 @@
 
 // test <stdlib.h>
 
-// ::aligned_alloc is provided by the C library, but it's marked as unavailable
-// until macOS 10.15
-// XFAIL: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}}
-
-// ::aligned_alloc is not implemented on Windows
-// XFAIL: target={{.+}}-pc-windows-{{.+}}
-
 #include <stdlib.h>
 #include <type_traits>
 #include <cassert>
@@ -139,9 +132,7 @@ int main(int, char**)
     static_assert((std::is_same<decltype(rand()), int>::value), "");
     static_assert((std::is_same<decltype(srand(0)), void>::value), "");
 
-#if TEST_STD_VER > 14
-    static_assert((std::is_same<decltype(aligned_alloc(1, 0)), void*>::value), "");
-#endif
+    // aligned_alloc tested in stdlib_h.aligned_alloc.compile.pass.cpp
 
     void* pv = 0;
     void (*handler)() = 0;

libcxx/test/std/language.support/support.runtime/cstdlib.aligned_alloc.compile.pass.cpp

@@ -0,0 +1,24 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// test <cstdlib>
+// std::aligned_alloc
+
+// UNSUPPORTED: c++03, c++11, c++14
+
+// ::aligned_alloc is provided by the C library, but it's marked as unavailable
+// until macOS 10.15
+// XFAIL: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}}
+
+// ::aligned_alloc is not implemented on Windows
+// XFAIL: target={{.+}}-pc-windows-{{.+}}
+
+#include <cstdlib>
+#include <type_traits>
+
+static_assert(std::is_same<decltype(std::aligned_alloc(1, 0)), void*>::value, "");

libcxx/test/std/language.support/support.runtime/cstdlib.pass.cpp

@@ -8,13 +8,6 @@
 
 // test <cstdlib>
 
-// ::aligned_alloc is provided by the C library, but it's marked as unavailable
-// until macOS 10.15
-// XFAIL: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}}
-
-// ::aligned_alloc is not implemented on Windows
-// XFAIL: target={{.+}}-pc-windows-{{.+}}
-
 #include <cstdlib>
 #include <type_traits>
 #include <cassert>
@@ -126,9 +119,7 @@ int main(int, char**)
     static_assert((std::is_same<decltype(std::rand()), int>::value), "");
     static_assert((std::is_same<decltype(std::srand(0)), void>::value), "");
 
-#if TEST_STD_VER > 14
-    static_assert((std::is_same<decltype(std::aligned_alloc(1, 0)), void*>::value), "");
-#endif
+    // std::aligned_alloc tested in cstdlib.aligned_alloc.compile.pass.cpp
 
     void* pv = 0;
     void (*handler)() = 0;

libcxx/test/std/language.support/support.runtime/ctime.pass.cpp

@@ -8,10 +8,6 @@
 
 // test <ctime>
 
-// ::timespec_get is provided by the C library, but it's marked as
-// unavailable until macOS 10.15
-// XFAIL: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}}
-
 #include <ctime>
 #include <type_traits>
 #include "test_macros.h"
@@ -36,10 +32,7 @@ int main(int, char**)
     std::size_t s = 0;
     std::time_t t = 0;
     std::tm tm = {};
-#if TEST_STD_VER > 14
-    std::timespec tmspec = {};
-    ((void)tmspec); // Prevent unused warning
-#endif
+    // std::timespec and std::timespec_get tested in ctime.timespec.compile.pass.cpp
     ((void)c); // Prevent unused warning
     ((void)s); // Prevent unused warning
     ((void)t); // Prevent unused warning
@@ -48,9 +41,6 @@ int main(int, char**)
     static_assert((std::is_same<decltype(std::difftime(t,t)), double>::value), "");
     static_assert((std::is_same<decltype(std::mktime(&tm)), std::time_t>::value), "");
     static_assert((std::is_same<decltype(std::time(&t)), std::time_t>::value), "");
-#if TEST_STD_VER > 14
-    static_assert((std::is_same<decltype(std::timespec_get(&tmspec, 0)), int>::value), "");
-#endif
 #ifndef _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
     static_assert((std::is_same<decltype(std::asctime(&tm)), char*>::value), "");
     static_assert((std::is_same<decltype(std::ctime(&t)), char*>::value), "");

libcxx/test/std/language.support/support.runtime/ctime.timespec.compile.pass.cpp

@@ -0,0 +1,22 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// test <ctime>
+// std::timespec and std::timespec_get
+
+// UNSUPPORTED: c++03, c++11, c++14
+
+// ::timespec_get is provided by the C library, but it's marked as
+// unavailable until macOS 10.15
+// XFAIL: use_system_cxx_lib && target={{.+}}-apple-macosx10.{{9|10|11|12|13|14}}
+
+#include <ctime>
+#include <type_traits>
+
+std::timespec tmspec = {};
+static_assert(std::is_same<decltype(std::timespec_get(&tmspec, 0)), int>::value, "");