[libc++] Remove libc++'s own stdint.h and locale.h

[ldionne]

These headers are not doing anything beyond the system or compiler provided equivalent headers, so there's no real reason to keep them around. Reducing the number of C headers we provide in libc++ simplifies our header layering and reduces the potential for confusion when headers are layered incorrectly.

[llvmbot]

@llvm/pr-subscribers-libcxx

Author: Louis Dionne (ldionne)

Changes

These headers are not doing anything beyond the system or compiler provided equivalent headers, so there's no real reason to keep them around. Reducing the number of C headers we provide in libc++ simplifies our header layering and reduces the potential for confusion when headers are layered incorrectly.

---

Full diff: https://github.com/llvm/llvm-project/pull/107436.diff

8 Files Affected:

• (modified) libcxx/include/CMakeLists.txt (-2)
• (modified) libcxx/include/__std_clang_module (-4)
• (modified) libcxx/include/clocale (-8)
• (removed) libcxx/include/locale.h (-46)
• (modified) libcxx/include/module.modulemap (-8)
• (removed) libcxx/include/stdint.h (-127)
• (modified) libcxx/test/libcxx/depr/depr.c.headers/extern_c.pass.cpp (-3)
• (modified) libcxx/utils/libcxx/header_information.py (-2)

diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index 0f43916dae4384..762c68a9231e42 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -963,7 +963,6 @@ set(files
   limits
   list
   locale
-  locale.h
   map
   math.h
   mdspan
@@ -994,7 +993,6 @@ set(files
   stdbool.h
   stddef.h
   stdexcept
-  stdint.h
   stdio.h
   stdlib.h
   stop_token
diff --git a/libcxx/include/__std_clang_module b/libcxx/include/__std_clang_module
index 18d6ce6b46c1f6..c0e15ffb7f5962 100644
--- a/libcxx/include/__std_clang_module
+++ b/libcxx/include/__std_clang_module
@@ -126,9 +126,6 @@
 #include <limits>
 #include <list>
 #if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
-#  include <locale.h>
-#endif
-#if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
 #  include <locale>
 #endif
 #include <map>
@@ -172,7 +169,6 @@
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdexcept>
-#include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #if !defined(_LIBCPP_HAS_NO_THREADS)
diff --git a/libcxx/include/clocale b/libcxx/include/clocale
index c689a64be288a3..4d53aa7eb29b29 100644
--- a/libcxx/include/clocale
+++ b/libcxx/include/clocale
@@ -38,14 +38,6 @@ lconv* localeconv();
 
 #include <locale.h>
 
-#ifndef _LIBCPP_LOCALE_H
-#   error <clocale> tried including <locale.h> but didn't find libc++'s <locale.h> header. \
-          This usually means that your header search paths are not configured properly. \
-          The header search paths should contain the C++ Standard Library headers before \
-          any C Standard Library, and you are probably using compiler flags that make that \
-          not be the case.
-#endif
-
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #  pragma GCC system_header
 #endif
diff --git a/libcxx/include/locale.h b/libcxx/include/locale.h
deleted file mode 100644
index 425bf47d437ac8..00000000000000
--- a/libcxx/include/locale.h
+++ /dev/null
@@ -1,46 +0,0 @@
-// -*- C++ -*-
-//===----------------------------------------------------------------------===//
-//
-// 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_LOCALE_H
-#define _LIBCPP_LOCALE_H
-
-/*
-    locale.h synopsis
-
-Macros:
-
-    LC_ALL
-    LC_COLLATE
-    LC_CTYPE
-    LC_MONETARY
-    LC_NUMERIC
-    LC_TIME
-
-Types:
-
-    lconv
-
-Functions:
-
-   setlocale
-   localeconv
-
-*/
-
-#include <__config>
-
-#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
-#  pragma GCC system_header
-#endif
-
-#if __has_include_next(<locale.h>)
-#  include_next <locale.h>
-#endif
-
-#endif // _LIBCPP_LOCALE_H
diff --git a/libcxx/include/module.modulemap b/libcxx/include/module.modulemap
index 3abc11723a5a92..ded4647cb88a48 100644
--- a/libcxx/include/module.modulemap
+++ b/libcxx/include/module.modulemap
@@ -511,10 +511,6 @@ module std_inttypes_h [system] {
   export *
 }
 // <iso646.h> provided by compiler.
-module std_locale_h [system] {
-  header "locale.h"
-  export *
-}
 module std_math_h [system] {
   header "math.h"
   export *
@@ -537,10 +533,6 @@ module std_stddef_h [system] {
   textual header "stddef.h"
   export *
 }
-module std_stdint_h [system] {
-  header "stdint.h"
-  export *
-}
 module std_stdio_h [system] {
   // <stdio.h>'s __need_* macros require textual inclusion.
   textual header "stdio.h"
diff --git a/libcxx/include/stdint.h b/libcxx/include/stdint.h
deleted file mode 100644
index 35e5b8cbdad264..00000000000000
--- a/libcxx/include/stdint.h
+++ /dev/null
@@ -1,127 +0,0 @@
-// -*- C++ -*-
-//===----------------------------------------------------------------------===//
-//
-// 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_STDINT_H
-// AIX system headers need stdint.h to be re-enterable while _STD_TYPES_T
-// is defined until an inclusion of it without _STD_TYPES_T occurs, in which
-// case the header guard macro is defined.
-#if !defined(_AIX) || !defined(_STD_TYPES_T)
-#  define _LIBCPP_STDINT_H
-#endif // _STD_TYPES_T
-
-/*
-    stdint.h synopsis
-
-Macros:
-
-    INT8_MIN
-    INT16_MIN
-    INT32_MIN
-    INT64_MIN
-
-    INT8_MAX
-    INT16_MAX
-    INT32_MAX
-    INT64_MAX
-
-    UINT8_MAX
-    UINT16_MAX
-    UINT32_MAX
-    UINT64_MAX
-
-    INT_LEAST8_MIN
-    INT_LEAST16_MIN
-    INT_LEAST32_MIN
-    INT_LEAST64_MIN
-
-    INT_LEAST8_MAX
-    INT_LEAST16_MAX
-    INT_LEAST32_MAX
-    INT_LEAST64_MAX
-
-    UINT_LEAST8_MAX
-    UINT_LEAST16_MAX
-    UINT_LEAST32_MAX
-    UINT_LEAST64_MAX
-
-    INT_FAST8_MIN
-    INT_FAST16_MIN
-    INT_FAST32_MIN
-    INT_FAST64_MIN
-
-    INT_FAST8_MAX
-    INT_FAST16_MAX
-    INT_FAST32_MAX
-    INT_FAST64_MAX
-
-    UINT_FAST8_MAX
-    UINT_FAST16_MAX
-    UINT_FAST32_MAX
-    UINT_FAST64_MAX
-
-    INTPTR_MIN
-    INTPTR_MAX
-    UINTPTR_MAX
-
-    INTMAX_MIN
-    INTMAX_MAX
-
-    UINTMAX_MAX
-
-    PTRDIFF_MIN
-    PTRDIFF_MAX
-
-    SIG_ATOMIC_MIN
-    SIG_ATOMIC_MAX
-
-    SIZE_MAX
-
-    WCHAR_MIN
-    WCHAR_MAX
-
-    WINT_MIN
-    WINT_MAX
-
-    INT8_C(value)
-    INT16_C(value)
-    INT32_C(value)
-    INT64_C(value)
-
-    UINT8_C(value)
-    UINT16_C(value)
-    UINT32_C(value)
-    UINT64_C(value)
-
-    INTMAX_C(value)
-    UINTMAX_C(value)
-
-*/
-
-#include <__config>
-
-#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
-#  pragma GCC system_header
-#endif
-
-/* C99 stdlib (e.g. glibc < 2.18) does not provide macros needed
-   for C++11 unless __STDC_LIMIT_MACROS and __STDC_CONSTANT_MACROS
-   are defined
-*/
-#if defined(__cplusplus) && !defined(__STDC_LIMIT_MACROS)
-#  define __STDC_LIMIT_MACROS
-#endif
-#if defined(__cplusplus) && !defined(__STDC_CONSTANT_MACROS)
-#  define __STDC_CONSTANT_MACROS
-#endif
-
-#if __has_include_next(<stdint.h>)
-#  include_next <stdint.h>
-#endif
-
-#endif // _LIBCPP_STDINT_H
diff --git a/libcxx/test/libcxx/depr/depr.c.headers/extern_c.pass.cpp b/libcxx/test/libcxx/depr/depr.c.headers/extern_c.pass.cpp
index 9fa4021e5c1ead..63ca6643797132 100644
--- a/libcxx/test/libcxx/depr/depr.c.headers/extern_c.pass.cpp
+++ b/libcxx/test/libcxx/depr/depr.c.headers/extern_c.pass.cpp
@@ -26,9 +26,6 @@ extern "C" {
 #include <inttypes.h>
 #include <iso646.h>
 #include <limits.h>
-#ifndef _LIBCPP_HAS_NO_LOCALIZATION
-#   include <locale.h>
-#endif
 #include <math.h>
 #include <setjmp.h>
 #include <signal.h>
diff --git a/libcxx/utils/libcxx/header_information.py b/libcxx/utils/libcxx/header_information.py
index 166c9a77c08e70..e5a916da0b44a0 100644
--- a/libcxx/utils/libcxx/header_information.py
+++ b/libcxx/utils/libcxx/header_information.py
@@ -15,7 +15,6 @@
 
     # headers with #error directives
     "ios": "!defined(_LIBCPP_HAS_NO_LOCALIZATION)",
-    "locale.h": "!defined(_LIBCPP_HAS_NO_LOCALIZATION)",
     # transitive includers of the above headers
     "clocale": "!defined(_LIBCPP_HAS_NO_LOCALIZATION)",
     "codecvt": "!defined(_LIBCPP_HAS_NO_LOCALIZATION)",
@@ -69,7 +68,6 @@
     "istream": "// UNSUPPORTED: no-localization",
     "latch": "// UNSUPPORTED: no-threads, c++03, c++11, c++14, c++17",
     "locale": "// UNSUPPORTED: no-localization",
-    "locale.h": "// UNSUPPORTED: no-localization",
     "mutex": "// UNSUPPORTED: no-threads, c++03",
     "ostream": "// UNSUPPORTED: no-localization",
     "print": "// UNSUPPORTED: no-filesystem, c++03, c++11, c++14, c++17, c++20, availability-fp_to_chars-missing", # TODO PRINT investigate