[libc++] Remove libc++'s own stdint.h and locale.h (#107436)

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

@@ -967,7 +967,6 @@ set(files
   limits
   list
   locale
-  locale.h
   map
   math.h
   mdspan
@@ -998,7 +997,6 @@ set(files
   stdbool.h
   stddef.h
   stdexcept
-  stdint.h
   stdio.h
   stdlib.h
   stop_token

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/cstdint

@@ -144,14 +144,6 @@ Types:
 
 #include <stdint.h>
 
-#ifndef _LIBCPP_STDINT_H
-#   error <cstdint> tried including <stdint.h> but didn't find libc++'s <stdint.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

@@ -2184,10 +2184,6 @@ module std_inttypes_h [system] {
   header "inttypes.h"
   export *
 }
-module std_locale_h [system] {
-  header "locale.h"
-  export *
-}
 module std_math_h [system] {
   header "math.h"
   export *
@@ -2204,10 +2200,6 @@ module std_stddef_h [system] {
   // <stddef.h>'s __need_* macros require textual inclusion.
   textual header "stddef.h"
 }
-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)",
@@ -53,7 +52,6 @@
     "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