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

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.

Author: ldionne

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

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)

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

libcxx/include/locale.h

@@ -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"

libcxx/include/module.modulemap

@@ -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>

libcxx/include/stdint.h

@@ -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