Move the feature test macros script to the utils directory.

It doesn't make a lot of sense to keep it with the tests,
deep into the test suite directonies.

llvm-svn: 352970

1 files changed, 976 insertions, 0 deletions

diff --git a/libcxx/utils/generate_feature_test_macro_components.py b/libcxx/utils/generate_feature_test_macro_components.py
new file mode 100755
index 00000000000..2bd80a858d2
--- /dev/null
+++ b/libcxx/utils/generate_feature_test_macro_components.py
@@ -0,0 +1,976 @@
+#!/usr/bin/env python
+
+import os
+import tempfile
+
+def get_libcxx_paths():
+  utils_path = os.path.dirname(os.path.abspath(__file__))
+  script_name = os.path.basename(__file__)
+  assert os.path.exists(utils_path)
+  src_root = os.path.dirname(utils_path)
+  include_path = os.path.join(src_root, 'include')
+  assert os.path.exists(include_path)
+  docs_path = os.path.join(src_root, 'docs')
+  assert os.path.exists(docs_path)
+  macro_test_path = os.path.join(src_root, 'test', 'std', 'language.support',
+                            'support.limits', 'support.limits.general')
+  assert os.path.exists(macro_test_path)
+  assert os.path.exists(os.path.join(macro_test_path, 'version.version.pass.cpp'))
+  return script_name, src_root, include_path, docs_path, macro_test_path
+
+
+script_name, source_root, include_path, docs_path, macro_test_path = get_libcxx_paths()
+
+def has_header(h):
+  h_path = os.path.join(include_path, h)
+  return os.path.exists(h_path)
+
+def add_version_header(tc):
+    tc["headers"].append("version")
+    return tc
+
+feature_test_macros = sorted([ add_version_header(x) for x in [
+  # C++14 macros
+  {"name": "__cpp_lib_integer_sequence",
+   "values": {
+      "c++14": 201304L
+    },
+    "headers": ["utility"],
+  },
+  {"name": "__cpp_lib_exchange_function",
+   "values": {
+     "c++14": 201304L
+   },
+   "headers": ["utility"],
+  },
+  {"name": "__cpp_lib_tuples_by_type",
+   "values": {
+     "c++14": 201304L
+   },
+   "headers": ["utility", "tuple"],
+  },
+  {"name": "__cpp_lib_tuple_element_t",
+   "values": {
+     "c++14": 201402L
+   },
+   "headers": ["tuple"],
+  },
+  {"name": "__cpp_lib_make_unique",
+   "values": {
+     "c++14": 201304L
+   },
+   "headers": ["memory"],
+  },
+  {"name": "__cpp_lib_transparent_operators",
+   "values": {
+     "c++14": 201210L,
+     "c++17": 201510L,
+   },
+   "headers": ["functional"],
+  },
+  {"name": "__cpp_lib_integral_constant_callable",
+   "values": {
+     "c++14": 201304L
+   },
+   "headers": ["type_traits"],
+  },
+  {"name": "__cpp_lib_transformation_trait_aliases",
+   "values": {
+     "c++14": 201304L,
+   },
+   "headers": ["type_traits"]
+  },
+  {"name": "__cpp_lib_result_of_sfinae",
+   "values": {
+     "c++14": 201210L,
+   },
+   "headers": ["functional", "type_traits"]
+  },
+  {"name": "__cpp_lib_is_final",
+   "values": {
+     "c++14": 201402L,
+   },
+   "headers": ["type_traits"]
+  },
+  {"name": "__cpp_lib_is_null_pointer",
+   "values": {
+     "c++14": 201309L,
+   },
+   "headers": ["type_traits"]
+  },
+  {"name": "__cpp_lib_chrono_udls",
+   "values": {
+     "c++14": 201304L,
+   },
+   "headers": ["chrono"]
+  },
+  {"name": "__cpp_lib_string_udls",
+   "values": {
+     "c++14": 201304L,
+   },
+   "headers": ["string"]
+  },
+  {"name": "__cpp_lib_generic_associative_lookup",
+   "values": {
+     "c++14": 201304L,
+   },
+   "headers": ["map", "set"]
+  },
+  {"name": "__cpp_lib_null_iterators",
+   "values": {
+     "c++14": 201304L,
+   },
+   "headers": ["iterator"]
+  },
+  {"name": "__cpp_lib_make_reverse_iterator",
+   "values": {
+     "c++14": 201402L,
+   },
+   "headers": ["iterator"]
+  },
+  {"name": "__cpp_lib_robust_nonmodifying_seq_ops",
+   "values": {
+     "c++14": 201304L,
+   },
+   "headers": ["algorithm"]
+  },
+  {"name": "__cpp_lib_complex_udls",
+   "values": {
+     "c++14": 201309L,
+   },
+   "headers": ["complex"]
+  },
+  {"name": "__cpp_lib_quoted_string_io",
+   "values": {
+     "c++14": 201304L,
+   },
+   "headers": ["iomanip"]
+  },
+  {"name": "__cpp_lib_shared_timed_mutex",
+   "values": {
+     "c++14": 201402L,
+   },
+   "headers": ["shared_mutex"],
+   "depends": "!defined(_LIBCPP_HAS_NO_THREADS)",
+   "internal_depends": "!defined(_LIBCPP_HAS_NO_THREADS)",
+  },
+  # C++17 macros
+  {"name": "__cpp_lib_atomic_is_always_lock_free",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["atomic"],
+   "depends": "!defined(_LIBCPP_HAS_NO_THREADS)",
+   "internal_depends": "!defined(_LIBCPP_HAS_NO_THREADS)",
+  },
+  {"name": "__cpp_lib_filesystem",
+   "values": {
+     "c++17": 201703L,
+   },
+   "headers": ["filesystem"]
+  },
+  {"name": "__cpp_lib_invoke",
+   "values": {
+     "c++17": 201411L,
+   },
+   "headers": ["functional"]
+  },
+  {"name": "__cpp_lib_void_t",
+   "values": {
+     "c++17": 201411L,
+   },
+   "headers": ["type_traits"]
+  },
+  {"name": "__cpp_lib_node_extract",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["map", "set", "unordered_map", "unordered_set"]
+  },
+  {"name": "__cpp_lib_byte",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["cstddef"],
+   },
+  {"name": "__cpp_lib_hardware_interference_size",
+   "values": {
+     "c++17": 201703L,
+   },
+   "headers": ["new"],
+   },
+  {"name": "__cpp_lib_launder",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["new"],
+   },
+  {"name": "__cpp_lib_uncaught_exceptions",
+   "values": {
+     "c++17": 201411L,
+   },
+   "headers": ["exception"],
+   },
+  {"name": "__cpp_lib_as_const",
+   "values": {
+     "c++17": 201510L,
+   },
+   "headers": ["utility"],
+   },
+  {"name": "__cpp_lib_make_from_tuple",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["tuple"],
+   },
+  {"name": "__cpp_lib_apply",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["tuple"],
+   },
+  {"name": "__cpp_lib_optional",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["optional"],
+   },
+  {"name": "__cpp_lib_variant",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["variant"],
+   },
+  {"name": "__cpp_lib_any",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["any"],
+   },
+  {"name": "__cpp_lib_addressof_constexpr",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["memory"],
+   "depends": "TEST_HAS_BUILTIN(__builtin_addressof) || TEST_GCC_VER >= 700",
+   "internal_depends": "!defined(_LIBCPP_HAS_NO_BUILTIN_ADDRESSOF)",
+   },
+  {"name": "__cpp_lib_raw_memory_algorithms",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["memory"],
+   },
+  {"name": "__cpp_lib_enable_shared_from_this",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["memory"],
+   },
+  {"name": "__cpp_lib_shared_ptr_weak_type",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["memory"],
+   },
+  {"name": "__cpp_lib_shared_ptr_arrays",
+   "values": {
+     "c++17": 201611L,
+   },
+   "headers": ["memory"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_memory_resource",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["memory_resource"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_boyer_moore_searcher",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["functional"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_not_fn",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["functional"],
+   },
+  {"name": "__cpp_lib_bool_constant",
+   "values": {
+     "c++17": 201505L,
+   },
+   "headers": ["type_traits"],
+   },
+  {"name": "__cpp_lib_type_trait_variable_templates",
+   "values": {
+     "c++17": 201510L,
+   },
+   "headers": ["type_traits"],
+   },
+  {"name": "__cpp_lib_logical_traits",
+   "values": {
+     "c++17": 201510L,
+   },
+   "headers": ["type_traits"],
+   },
+  {"name": "__cpp_lib_is_swappable",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["type_traits"],
+   },
+  {"name": "__cpp_lib_is_invocable",
+   "values": {
+     "c++17": 201703L,
+   },
+   "headers": ["type_traits"],
+   },
+  {"name": "__cpp_lib_has_unique_object_representations",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["type_traits"],
+   "depends": "TEST_HAS_BUILTIN_IDENTIFIER(__has_unique_object_representations) || TEST_GCC_VER >= 700",
+   "internal_depends": "defined(_LIBCPP_HAS_UNIQUE_OBJECT_REPRESENTATIONS)",
+   },
+  {"name": "__cpp_lib_is_aggregate",
+   "values": {
+     "c++17": 201703L,
+   },
+   "headers": ["type_traits"],
+   "depends": "TEST_HAS_BUILTIN_IDENTIFIER(__is_aggregate) || TEST_GCC_VER_NEW >= 7001",
+   "internal_depends": "!defined(_LIBCPP_HAS_NO_IS_AGGREGATE)",
+   },
+  {"name": "__cpp_lib_chrono",
+   "values": {
+     "c++17": 201611L,
+   },
+   "headers": ["chrono"],
+   },
+  {"name": "__cpp_lib_execution",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["execution"],
+   "unimplemented": True
+   },
+  {"name": "__cpp_lib_parallel_algorithm",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["algorithm", "numeric"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_to_chars",
+   "values": {
+     "c++17": 201611L,
+   },
+   "headers": ["utility"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_string_view",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["string", "string_view"],
+   },
+  {"name": "__cpp_lib_allocator_traits_is_always_equal",
+   "values": {
+     "c++17": 201411L,
+   },
+   "headers": ["memory", "scoped_allocator", "string", "deque", "forward_list", "list", "vector", "map", "set", "unordered_map", "unordered_set"],
+   },
+  {"name": "__cpp_lib_incomplete_container_elements",
+   "values": {
+     "c++17": 201505L,
+   },
+   "headers": ["forward_list", "list", "vector"],
+   },
+  {"name": "__cpp_lib_map_try_emplace",
+   "values": {
+     "c++17": 201411L,
+   },
+   "headers": ["map"],
+   },
+  {"name": "__cpp_lib_unordered_map_try_emplace",
+   "values": {
+     "c++17": 201411L,
+   },
+   "headers": ["unordered_map"],
+   },
+  {"name": "__cpp_lib_array_constexpr",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["iterator", "array"],
+   },
+  {"name": "__cpp_lib_nonmember_container_access",
+   "values": {
+     "c++17": 201411L,
+   },
+   "headers": ["iterator", "array", "deque", "forward_list", "list", "map", "regex",
+               "set", "string", "unordered_map", "unordered_set", "vector"],
+   },
+  {"name": "__cpp_lib_sample",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["algorithm"],
+   },
+  {"name": "__cpp_lib_clamp",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["algorithm"],
+   },
+  {"name": "__cpp_lib_gcd_lcm",
+   "values": {
+     "c++17": 201606L,
+   },
+   "headers": ["numeric"],
+   },
+  {"name": "__cpp_lib_hypot",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["cmath"],
+   },
+  {"name": "__cpp_lib_math_special_functions",
+   "values": {
+     "c++17": 201603L,
+   },
+   "headers": ["cmath"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_shared_mutex",
+   "values": {
+     "c++17": 201505L,
+   },
+   "headers": ["shared_mutex"],
+   "depends": "!defined(_LIBCPP_HAS_NO_THREADS)",
+   "internal_depends": "!defined(_LIBCPP_HAS_NO_THREADS)",
+   },
+  {"name": "__cpp_lib_scoped_lock",
+   "values": {
+     "c++17": 201703L,
+   },
+   "headers": ["mutex"],
+   },
+  # C++2a
+  {"name": "__cpp_lib_char8_t",
+   "values": {
+     "c++2a": 201811L,
+   },
+   "headers": ["atomic", "filesystem", "istream", "limits", "locale", "ostream",
+               "string", "string_view"],
+   "depends": "defined(__cpp_char8_t)",
+   "internal_depends": "!defined(_LIBCPP_NO_HAS_CHAR8_T)",
+   },
+  {"name": "__cpp_lib_erase_if",
+   "values": {
+     "c++2a": 201811L,
+   },
+   "headers": ["string", "deque", "forward_list", "list", "vector", "map",
+               "set", "unordered_map", "unordered_set"]
+  },
+  {"name": "__cpp_lib_destroying_delete",
+   "values": {
+     "c++2a": 201806L,
+   },
+   "headers": ["new"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_three_way_comparison",
+   "values": {
+     "c++2a": 201711L,
+   },
+   "headers": ["compare"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_concepts",
+   "values": {
+     "c++2a": 201806L,
+   },
+   "headers": ["concepts"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_constexpr_swap_algorithms",
+   "values": {
+     "c++2a": 201806L,
+   },
+   "headers": ["algorithm"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_constexpr_misc",
+   "values": {
+     "c++2a": 201811L,
+   },
+   "headers": ["array", "functional", "iterator", "string_view", "tuple", "utility"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_bind_front",
+   "values": {
+     "c++2a": 201811L,
+   },
+   "headers": ["functional"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_is_constant_evaluated",
+   "values": {
+     "c++2a": 201811L,
+   },
+   "headers": ["type_traits"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_list_remove_return_type",
+   "values": {
+     "c++2a": 201806L,
+   },
+   "headers": ["forward_list", "list"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_generic_unordered_lookup",
+   "values": {
+     "c++2a": 201811L,
+   },
+   "headers": ["unordered_map", "unordered_set"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_ranges",
+   "values": {
+     "c++2a": 201811L,
+   },
+   "headers": ["algorithm", "functional", "iterator", "memory", "ranges"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_bit_cast",
+   "values": {
+     "c++2a": 201806L,
+   },
+   "headers": ["bit"],
+   "unimplemented": True,
+   },
+  {"name": "__cpp_lib_atomic_ref",
+   "values": {
+     "c++2a": 201806L,
+   },
+   "headers": ["atomic"],
+   "unimplemented": True,
+   "depends": "!defined(_LIBCPP_HAS_NO_THREADS)",
+   "internal_depends": "!defined(_LIBCPP_HAS_NO_THREADS)",
+   },
+]], key=lambda tc: tc["name"])
+
+def get_std_dialects():
+  std_dialects = ['c++14', 'c++17', 'c++2a']
+  return list(std_dialects)
+
+def get_first_std(d):
+    for s in get_std_dialects():
+        if s in d.keys():
+            return s
+    return None
+
+def get_last_std(d):
+  rev_dialects = get_std_dialects()
+  rev_dialects.reverse()
+  for s in rev_dialects:
+    if s in d.keys():
+      return s
+  return None
+
+def get_std_before(d, std):
+  std_dialects = get_std_dialects()
+  candidates = std_dialects[0:std_dialects.index(std)]
+  candidates.reverse()
+  for cand in candidates:
+    if cand in d.keys():
+      return cand
+  return None
+
+def get_value_before(d, std):
+  new_std = get_std_before(d, std)
+  if new_std is None:
+    return None
+  return d[new_std]
+
+def get_for_std(d, std):
+  # This catches the C++11 case for which there should be no defined feature
+  # test macros.
+  std_dialects = get_std_dialects()
+  if std not in std_dialects:
+    return None
+  # Find the value for the newest C++ dialect between C++14 and std
+  std_list = list(std_dialects[0:std_dialects.index(std)+1])
+  std_list.reverse()
+  for s in std_list:
+    if s in d.keys():
+      return d[s]
+  return None
+
+
+"""
+  Functions to produce the <version> header
+"""
+
+def produce_macros_definition_for_std(std):
+  result = ""
+  indent = 56
+  for tc in feature_test_macros:
+    if std not in tc["values"]:
+      continue
+    inner_indent = 1
+    if 'depends' in tc.keys():
+      assert 'internal_depends' in tc.keys()
+      result += "# if %s\n" % tc["internal_depends"]
+      inner_indent += 2
+    if get_value_before(tc["values"], std) is not None:
+      assert 'depends' not in tc.keys()
+      result += "# undef  %s\n" % tc["name"]
+    line = "#%sdefine %s" % ((" " * inner_indent), tc["name"])
+    line += " " * (indent - len(line))
+    line += "%sL" % tc["values"][std]
+    if 'unimplemented' in tc.keys():
+      line = "// " + line
+    result += line
+    result += "\n"
+    if 'depends' in tc.keys():
+      result += "# endif\n"
+  return result
+
+def chunks(l, n):
+  """Yield successive n-sized chunks from l."""
+  for i in range(0, len(l), n):
+    yield l[i:i + n]
+
+def produce_version_synopsis():
+  indent = 56
+  header_indent = 56 + len("20XXYYL ")
+  result = ""
+  def indent_to(s, val):
+    if len(s) >= val:
+      return s
+    s += " " * (val - len(s))
+    return s
+  line = indent_to("Macro name", indent) + "Value"
+  line = indent_to(line, header_indent) + "Headers"
+  result += line + "\n"
+  for tc in feature_test_macros:
+    prev_defined_std = get_last_std(tc["values"])
+    line = "{name: <{indent}}{value}L ".format(name=tc['name'], indent=indent,
+                                               value=tc["values"][prev_defined_std])
+    headers = list(tc["headers"])
+    headers.remove("version")
+    for chunk in chunks(headers, 3):
+      line = indent_to(line, header_indent)
+      chunk = ['<%s>' % header for header in chunk]
+      line += ' '.join(chunk)
+      result += line
+      result += "\n"
+      line = ""
+    while True:
+      prev_defined_std = get_std_before(tc["values"], prev_defined_std)
+      if prev_defined_std is None:
+        break
+      result += "%s%sL // %s\n" % (indent_to("", indent), tc["values"][prev_defined_std],
+                                prev_defined_std.replace("c++", "C++"))
+  return result
+
+
+def produce_version_header():
+  template="""// -*- C++ -*-
+//===--------------------------- version ----------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_VERSIONH
+#define _LIBCPP_VERSIONH
+
+/*
+  version synopsis
+
+{synopsis}
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER > 11
+{cxx14_macros}
+#endif
+
+#if _LIBCPP_STD_VER > 14
+{cxx17_macros}
+#endif
+
+#if _LIBCPP_STD_VER > 17
+{cxx2a_macros}
+#endif
+
+#endif // _LIBCPP_VERSIONH
+"""
+  return template.format(
+      synopsis=produce_version_synopsis().strip(),
+      cxx14_macros=produce_macros_definition_for_std('c++14').strip(),
+      cxx17_macros=produce_macros_definition_for_std('c++17').strip(),
+      cxx2a_macros=produce_macros_definition_for_std('c++2a').strip())
+
+"""
+    Functions to produce test files
+"""
+
+test_types = {
+  "undefined": """
+# ifdef {name}
+#   error "{name} should not be defined before {std_first}"
+# endif
+""",
+
+  "depends": """
+# if {depends}
+#   ifndef {name}
+#     error "{name} should be defined in {std}"
+#   endif
+#   if {name} != {value}
+#     error "{name} should have the value {value} in {std}"
+#   endif
+# else
+#   ifdef {name}
+#     error "{name} should not be defined when {depends} is not defined!"
+#   endif
+# endif
+""",
+
+  "unimplemented": """
+# if !defined(_LIBCPP_VERSION)
+#   ifndef {name}
+#     error "{name} should be defined in {std}"
+#   endif
+#   if {name} != {value}
+#     error "{name} should have the value {value} in {std}"
+#   endif
+# else // _LIBCPP_VERSION
+#   ifdef {name}
+#     error "{name} should not be defined because it is unimplemented in libc++!"
+#   endif
+# endif
+""",
+
+  "defined":"""
+# ifndef {name}
+#   error "{name} should be defined in {std}"
+# endif
+# if {name} != {value}
+#   error "{name} should have the value {value} in {std}"
+# endif
+"""
+}
+
+def generate_std_test(test_list, std):
+  result = ""
+  for tc in test_list:
+    val = get_for_std(tc["values"], std)
+    if val is not None:
+      val = "%sL" % val
+    if val is None:
+      result += test_types["undefined"].format(name=tc["name"], std_first=get_first_std(tc["values"]))
+    elif 'unimplemented' in tc.keys():
+      result += test_types["unimplemented"].format(name=tc["name"], value=val, std=std)
+    elif "depends" in tc.keys():
+      result += test_types["depends"].format(name=tc["name"], value=val, std=std, depends=tc["depends"])
+    else:
+      result +=  test_types["defined"].format(name=tc["name"], value=val, std=std)
+  return result
+
+def generate_synopsis(test_list):
+    max_name_len = max([len(tc["name"]) for tc in test_list])
+    indent = max_name_len + 8
+    def mk_line(prefix, suffix):
+        return "{prefix: <{max_len}}{suffix}\n".format(prefix=prefix, suffix=suffix,
+        max_len=indent)
+    result = ""
+    result += mk_line("/*  Constant", "Value")
+    for tc in test_list:
+        prefix = "    %s" % tc["name"]
+        for std in [s for s in get_std_dialects() if s in tc["values"].keys()]:
+            result += mk_line(prefix, "%sL [%s]" % (tc["values"][std], std.replace("c++", "C++")))
+            prefix = ""
+    result += "*/"
+    return result
+
+def is_threading_header_unsafe_to_include(h):
+  # NOTE: "<mutex>" does not blow up when included without threads.
+  return h in ['atomic', 'shared_mutex']
+
+def produce_tests():
+  headers = set([h for tc in feature_test_macros for h in tc["headers"]])
+  for h in headers:
+    test_list = [tc for tc in feature_test_macros if h in tc["headers"]]
+    if not has_header(h):
+      for tc in test_list:
+        assert 'unimplemented' in tc.keys()
+      continue
+    test_tags = ""
+    if is_threading_header_unsafe_to_include(h):
+      test_tags += '\n// UNSUPPORTED: libcpp-has-no-threads\n'
+    test_body = \
+"""//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// WARNING: This test was generated by {script_name}
+// and should not be edited manually.
+{test_tags}
+// <{header}>
+
+// Test the feature test macros defined by <{header}>
+
+{synopsis}
+
+#include <{header}>
+#include "test_macros.h"
+
+#if TEST_STD_VER < 14
+
+{cxx11_tests}
+
+#elif TEST_STD_VER == 14
+
+{cxx14_tests}
+
+#elif TEST_STD_VER == 17
+
+{cxx17_tests}
+
+#elif TEST_STD_VER > 17
+
+{cxx2a_tests}
+
+#endif // TEST_STD_VER > 17
+
+int main() {{}}
+""".format(script_name=script_name,
+           header=h,
+           test_tags=test_tags,
+           synopsis=generate_synopsis(test_list),
+           cxx11_tests=generate_std_test(test_list, 'c++11').strip(),
+           cxx14_tests=generate_std_test(test_list, 'c++14').strip(),
+           cxx17_tests=generate_std_test(test_list, 'c++17').strip(),
+           cxx2a_tests=generate_std_test(test_list, 'c++2a').strip())
+    test_name = "{header}.version.pass.cpp".format(header=h)
+    out_path = os.path.join(macro_test_path, test_name)
+    with open(out_path, 'w') as f:
+      f.write(test_body)
+
+"""
+    Produce documentation for the feature test macros
+"""
+
+def make_widths(grid):
+  widths = []
+  for i in range(0, len(grid[0])):
+    cell_width = 2 + max(reduce(lambda x,y: x+y, [[len(row[i])] for row in grid], []))
+    widths += [cell_width]
+  return widths
+
+def create_table(grid, indent):
+  indent_str = ' '*indent
+  col_widths = make_widths(grid)
+  num_cols = len(grid[0])
+  result = indent_str + add_divider(col_widths, 2)
+  header_flag = 2
+  for row_i in xrange(0, len(grid)):
+    row = grid[row_i]
+    result = result + indent_str + ' '.join([pad_cell(row[i], col_widths[i]) for i in range(0, len(row))]) + '\n'
+    is_cxx_header = row[0].startswith('**')
+    if row_i == len(grid) - 1:
+      header_flag = 2
+    result = result + indent_str + add_divider(col_widths, 1 if is_cxx_header else header_flag)
+    header_flag = 0
+  return result
+
+def add_divider(widths, header_flag):
+  if header_flag == 2:
+    return ' '.join(['='*w for w in widths]) + '\n'
+  if header_flag == 1:
+    return '-'.join(['-'*w for w in widths]) + '\n'
+  else:
+    return ' '.join(['-'*w for w in widths]) + '\n'
+
+def pad_cell(s, length, left_align=True):
+  padding = ((length - len(s)) * ' ')
+  return s + padding
+
+
+def get_status_table():
+  table = [["Macro Name", "Value"]]
+  for std in get_std_dialects():
+    table += [["**" + std.replace("c++", "C++ ") + "**", ""]]
+    for tc in feature_test_macros:
+      if std not in tc["values"].keys():
+        continue
+      value = "``%sL``" % tc["values"][std]
+      if 'unimplemented' in tc.keys():
+        value = '*unimplemented*'
+      table += [["``%s``" % tc["name"], value]]
+  return table
+
+def produce_docs():
+  doc_str = """.. _FeatureTestMacroTable:
+
+==========================
+Feature Test Macro Support
+==========================
+
+.. contents::
+   :local:
+
+Overview
+========
+
+This file documents the feature test macros currently supported by libc++.
+
+.. _feature-status:
+
+Status
+======
+
+.. table:: Current Status
+     :name: feature-status-table
+     :widths: auto
+     
+{status_tables}
+
+""".format(status_tables=create_table(get_status_table(), 4))
+
+  table_doc_path = os.path.join(docs_path, 'FeatureTestMacroTable.rst')
+  with open(table_doc_path, 'w') as f:
+    f.write(doc_str)
+
+def main():
+  with tempfile.NamedTemporaryFile(mode='w', prefix='version.', delete=False) as tmp_file:
+    print("producing new <version> header as %s" % tmp_file.name)
+    tmp_file.write(produce_version_header())
+  produce_tests()
+  produce_docs()
+
+
+if __name__ == '__main__':
+  main()