Implement feature test macros using a script.linaro-local/ci/tcwg_kernel/llvm-master-aarch64-next-allyesconfig

Summary:
This patch implements all the feature test macros libc++ currently supports, as specified by the standard or cppreference prior to C++2a.

The tests and `<version>` header are generated using a script. The script contains a table of each feature test macro, the headers it should be accessible from, and its values of each dialect of C++.
When a new feature test macro is added or needed, the table should be updated and the script re-run.



Reviewers: mclow.lists, jfb, serge-sans-paille

Reviewed By: mclow.lists

Subscribers: arphaman, jfb, ldionne, libcxx-commits

Differential Revision: https://reviews.llvm.org/D56750

1 files changed, 40 insertions, 24 deletions

diff --git a/libcxx/test/std/language.support/support.limits/support.limits.general/istream.version.pass.cpp b/libcxx/test/std/language.support/support.limits/support.limits.general/istream.version.pass.cpp
index 7ede323ca5a..195ca2d0b00 100644
--- a/libcxx/test/std/language.support/support.limits/support.limits.general/istream.version.pass.cpp
+++ b/libcxx/test/std/language.support/support.limits/support.limits.general/istream.version.pass.cpp
@@ -1,4 +1,3 @@
-
 //===----------------------------------------------------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
@@ -8,36 +7,53 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// <istream> feature macros
+// WARNING: This test was generated by generate_feature_test_macros_tests.py and
+// should not be edited manually.
+
+// <istream>
 
-/*  Constant                                    Value
-    __cpp_lib_char8_t                           201811L
+// Test the feature test macros defined by <istream>
 
+/*  Constant             Value
+    __cpp_lib_char8_t    201811L [C++2a]
 */
 
 #include <istream>
-#include <cassert>
 #include "test_macros.h"
 
-int main()
-{
-//  ensure that the macros that are supposed to be defined in <istream> are defined.
+#if TEST_STD_VER < 14
+
+# ifdef __cpp_lib_char8_t
+#   error "__cpp_lib_char8_t should not be defined before c++2a"
+# endif
+
+#elif TEST_STD_VER == 14
+
+# ifdef __cpp_lib_char8_t
+#   error "__cpp_lib_char8_t should not be defined before c++2a"
+# endif
+
+#elif TEST_STD_VER == 17
+
+# ifdef __cpp_lib_char8_t
+#   error "__cpp_lib_char8_t should not be defined before c++2a"
+# endif
+
+#elif TEST_STD_VER > 17
 
-#if TEST_STD_VER > 17 && defined(__cpp_char8_t)
-# if !defined(__cpp_lib_char8_t)  
-  LIBCPP_STATIC_ASSERT(false, "__cpp_lib_char8_t is not defined");
+# if defined(__cpp_char8_t)
+#   ifndef __cpp_lib_char8_t
+#     error "__cpp_lib_char8_t should be defined in c++2a"
+#   endif
+#   if __cpp_lib_char8_t != 201811L
+#     error "__cpp_lib_char8_t should have the value 201811L in c++2a"
+#   endif
 # else
-#  if __cpp_lib_char8_t < 201811L
-#   error "__cpp_lib_char8_t has an invalid value"
-#  endif
+#   ifdef __cpp_lib_char8_t
+#     error "__cpp_lib_char8_t should not be defined when defined(__cpp_char8_t) is not defined!"
+#   endif
 # endif
-#endif
-
-/*
-#if !defined(__cpp_lib_fooby)
-# error "__cpp_lib_fooby is not defined"
-#elif __cpp_lib_fooby < 201606L
-# error "__cpp_lib_fooby has an invalid value"
-#endif
-*/
-}
+
+#endif // TEST_STD_VER > 17
+
+int main() {}