[libcxx][gardening] Re-order includes across libcxx.

This commit alphabetizes all includes in libcxx. This is a NFC.

This can also serve as a pseudo "announcement" for how we should order these headers going forward (note: double underscores go before other headers).

Differential Revision: https://reviews.llvm.org/D102941

libcxx/include/__bsd_locale_fallbacks.h

@@ -13,9 +13,9 @@
 #ifndef _LIBCPP_BSD_LOCALE_FALLBACKS_DEFAULTS_H
 #define _LIBCPP_BSD_LOCALE_FALLBACKS_DEFAULTS_H
 
-#include <stdlib.h>
-#include <stdarg.h>
 #include <memory>
+#include <stdarg.h>
+#include <stdlib.h>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header

libcxx/include/__iterator/concepts.h

@@ -11,12 +11,12 @@
 #define _LIBCPP___ITERATOR_CONCEPTS_H
 
 #include <__config>
-#include <concepts>
 #include <__iterator/incrementable_traits.h>
-#include <__iterator/iterator_traits.h>
 #include <__iterator/iter_move.h>
+#include <__iterator/iterator_traits.h>
 #include <__iterator/readable_traits.h>
 #include <__memory/pointer_traits.h>
+#include <concepts>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header

libcxx/include/__iterator/iterator_traits.h

@@ -11,9 +11,9 @@
 #define _LIBCPP___ITERATOR_ITERATOR_TRAITS_H
 
 #include <__config>
-#include <concepts>
 #include <__iterator/incrementable_traits.h>
 #include <__iterator/readable_traits.h>
+#include <concepts>
 #include <type_traits>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)

libcxx/include/__memory/shared_ptr.h

@@ -10,8 +10,8 @@
 #ifndef _LIBCPP___MEMORY_SHARED_PTR_H
 #define _LIBCPP___MEMORY_SHARED_PTR_H
 
-#include <__config>
 #include <__availability>
+#include <__config>
 #include <__functional_base> // std::less, std::binary_function
 #include <__memory/addressof.h>
 #include <__memory/allocation_guard.h>

libcxx/include/__ranges/data.h

@@ -10,11 +10,10 @@
 #define _LIBCPP___RANGES_DATA_H
 
 #include <__config>
-
-#include <concepts>
 #include <__iterator/concepts.h>
 #include <__iterator/iterator_traits.h>
 #include <__ranges/access.h>
+#include <concepts>
 #include <type_traits>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)

libcxx/include/__ranges/size.h

@@ -10,8 +10,8 @@
 #define _LIBCPP___RANGES_SIZE_H
 
 #include <__config>
-#include <__iterator/iterator_traits.h>
 #include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
 #include <__ranges/access.h>
 #include <type_traits>
 

libcxx/include/__support/ibm/xlocale.h

@@ -10,9 +10,9 @@
 #ifndef _LIBCPP_SUPPORT_IBM_XLOCALE_H
 #define _LIBCPP_SUPPORT_IBM_XLOCALE_H
 
-#include <stdarg.h>
 #include <__support/ibm/locale_mgmt_aix.h>
 #include <__support/ibm/locale_mgmt_zos.h>
+#include <stdarg.h>
 
 #include "cstdlib"
 

libcxx/include/__support/openbsd/xlocale.h

@@ -10,10 +10,10 @@
 #ifndef _LIBCPP_SUPPORT_OPENBSD_XLOCALE_H
 #define _LIBCPP_SUPPORT_OPENBSD_XLOCALE_H
 
-#include <cstdlib>
-#include <clocale>
-#include <cwctype>
-#include <ctype.h>
 #include <__support/xlocale/__strtonum_fallback.h>
+#include <clocale>
+#include <cstdlib>
+#include <ctype.h>
+#include <cwctype>
 
 #endif

libcxx/include/__support/win32/limits_msvc_win32.h

@@ -17,8 +17,8 @@
 #error "This header should only be included when using Microsofts C1XX frontend"
 #endif
 
-#include <limits.h> // CHAR_BIT
 #include <float.h> // limit constants
+#include <limits.h> // CHAR_BIT
 #include <math.h> // HUGE_VAL
 #include <ymath.h> // internal MSVC header providing the needed functionality
 

libcxx/include/__support/win32/locale_win32.h

@@ -11,9 +11,9 @@
 #define _LIBCPP_SUPPORT_WIN32_LOCALE_WIN32_H
 
 #include <__config>
-#include <stdio.h>
-#include <locale.h> // _locale_t
 #include <__nullptr>
+#include <locale.h> // _locale_t
+#include <stdio.h>
 
 #define _X_ALL LC_ALL
 #define _X_COLLATE LC_COLLATE