diff --git a/libcxx/include/__locale_dir/locale_base_api.h b/libcxx/include/__locale_dir/locale_base_api.h
index 2355b4a840d734..8c000c558c5279 100644
--- a/libcxx/include/__locale_dir/locale_base_api.h
+++ b/libcxx/include/__locale_dir/locale_base_api.h
@@ -95,18 +95,4 @@ except that locale_t is used instead of the current global locale.
 The variadic functions may be implemented as templates with a parameter pack instead of variadic functions.
 */
 
-/*
-// TODO: These symbols are never actually used, but defined by one or more implementations. They should be removed.
-long strtol_l(const char* str, char** str_end, locale_t);
-unsigned long strtoul_l(const char* str, char** str_end, locale_t);
-long long wcstoll_l(const wchar_t* str, wchar_t** str_end, int base, locale_t);
-unsigned long long wcstoull_l(const wchar_t* str, wchar_t** str_end, int base, locale_t);
-long double wcstold_l(const wchar_t* str, wchar_t** str_end, int base, locale_t);
-int sprintf_l(char* str, const char* format, locale_t, ...);
-int vsprintf_l(char* str, const char* format, locale_t, va_list);
-int vsnprintf_l(char* str, size_t size, const char* format, locale_t, va_list);
-int isblank_l(int ch, locale_t);
-
-*/
-
 #endif // _LIBCPP___LOCALE_DIR_LOCALE_BASE_API_H
diff --git a/libcxx/include/__locale_dir/locale_base_api/android.h b/libcxx/include/__locale_dir/locale_base_api/android.h
index a33d2539f06548..9965d8bbf6a2ec 100644
--- a/libcxx/include/__locale_dir/locale_base_api/android.h
+++ b/libcxx/include/__locale_dir/locale_base_api/android.h
@@ -10,37 +10,29 @@
 #ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_ANDROID_H
 #define _LIBCPP___LOCALE_LOCALE_BASE_API_ANDROID_H
 
-#if defined(__BIONIC__)
+#include <stdlib.h>
 
-#  ifdef __cplusplus
+// FIXME: Is this actually required?
 extern "C" {
-#  endif
-
-#  include <stdlib.h>
-#  include <xlocale.h>
-
-#  ifdef __cplusplus
+#include <xlocale.h>
 }
-#  endif
 
-#  if defined(__ANDROID__)
-
-#    include <android/api-level.h>
-#    if __ANDROID_API__ < 21
-#      include <__support/xlocale/__posix_l_fallback.h>
-#    endif
+#include <android/api-level.h>
+#if __ANDROID_API__ < 21
+#  include <__support/xlocale/__posix_l_fallback.h>
+#endif
 
 // If we do not have this header, we are in a platform build rather than an NDK
 // build, which will always be at least as new as the ToT NDK, in which case we
 // don't need any of the inlines below since libc provides them.
-#    if __has_include(<android/ndk-version.h>)
-#      include <android/ndk-version.h>
+#if __has_include(<android/ndk-version.h>)
+#  include <android/ndk-version.h>
 // In NDK versions later than 16, locale-aware functions are provided by
 // legacy_stdlib_inlines.h
-#      if __NDK_MAJOR__ <= 16
-#        if __ANDROID_API__ < 21
-#          include <__support/xlocale/__strtonum_fallback.h>
-#        elif __ANDROID_API__ < 26
+#  if __NDK_MAJOR__ <= 16
+#    if __ANDROID_API__ < 21
+#      include <__support/xlocale/__strtonum_fallback.h>
+#    elif __ANDROID_API__ < 26
 
 inline _LIBCPP_HIDE_FROM_ABI float strtof_l(const char* __nptr, char** __endptr, locale_t) {
   return ::strtof(__nptr, __endptr);
@@ -50,15 +42,9 @@ inline _LIBCPP_HIDE_FROM_ABI double strtod_l(const char* __nptr, char** __endptr
   return ::strtod(__nptr, __endptr);
 }
 
-inline _LIBCPP_HIDE_FROM_ABI long strtol_l(const char* __nptr, char** __endptr, int __base, locale_t) {
-  return ::strtol(__nptr, __endptr, __base);
-}
-
-#        endif // __ANDROID_API__ < 26
+#    endif // __ANDROID_API__ < 26
 
-#      endif // __NDK_MAJOR__ <= 16
-#    endif   // __has_include(<android/ndk-version.h>)
-#  endif     // defined(__ANDROID__)
+#  endif // __NDK_MAJOR__ <= 16
+#endif   // __has_include(<android/ndk-version.h>)
 
-#endif // defined(__BIONIC__)
 #endif // _LIBCPP___LOCALE_LOCALE_BASE_API_ANDROID_H
diff --git a/libcxx/include/__locale_dir/locale_base_api/fuchsia.h b/libcxx/include/__locale_dir/locale_base_api/fuchsia.h
index f999bead234e5c..4c3440f981c6d0 100644
--- a/libcxx/include/__locale_dir/locale_base_api/fuchsia.h
+++ b/libcxx/include/__locale_dir/locale_base_api/fuchsia.h
@@ -10,13 +10,9 @@
 #ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_FUCHSIA_H
 #define _LIBCPP___LOCALE_LOCALE_BASE_API_FUCHSIA_H
 
-#if defined(__Fuchsia__)
-
-#  include <__support/xlocale/__posix_l_fallback.h>
-#  include <__support/xlocale/__strtonum_fallback.h>
-#  include <cstdlib>
-#  include <cwchar>
-
-#endif // defined(__Fuchsia__)
+#include <__support/xlocale/__posix_l_fallback.h>
+#include <__support/xlocale/__strtonum_fallback.h>
+#include <cstdlib>
+#include <cwchar>
 
 #endif // _LIBCPP___LOCALE_LOCALE_BASE_API_FUCHSIA_H
diff --git a/libcxx/include/__locale_dir/locale_base_api/ibm.h b/libcxx/include/__locale_dir/locale_base_api/ibm.h
index 5e89a1dc1e8a6d..01af20194428b9 100644
--- a/libcxx/include/__locale_dir/locale_base_api/ibm.h
+++ b/libcxx/include/__locale_dir/locale_base_api/ibm.h
@@ -58,11 +58,6 @@ inline _LIBCPP_HIDE_FROM_ABI long long strtoll_l(const char* __nptr, char** __en
   return ::strtoll(__nptr, __endptr, __base);
 }
 
-inline _LIBCPP_HIDE_FROM_ABI long strtol_l(const char* __nptr, char** __endptr, int __base, locale_t locale) {
-  __setAndRestore __newloc(locale);
-  return ::strtol(__nptr, __endptr, __base);
-}
-
 inline _LIBCPP_HIDE_FROM_ABI double strtod_l(const char* __nptr, char** __endptr, locale_t locale) {
   __setAndRestore __newloc(locale);
   return ::strtod(__nptr, __endptr);
@@ -84,11 +79,6 @@ strtoull_l(const char* __nptr, char** __endptr, int __base, locale_t locale) {
   return ::strtoull(__nptr, __endptr, __base);
 }
 
-inline _LIBCPP_HIDE_FROM_ABI unsigned long strtoul_l(const char* __nptr, char** __endptr, int __base, locale_t locale) {
-  __setAndRestore __newloc(locale);
-  return ::strtoul(__nptr, __endptr, __base);
-}
-
 inline _LIBCPP_HIDE_FROM_ABI
 _LIBCPP_ATTRIBUTE_FORMAT(__printf__, 2, 0) int vasprintf(char** strp, const char* fmt, va_list ap) {
   const size_t buff_size = 256;
diff --git a/libcxx/include/__locale_dir/locale_base_api/musl.h b/libcxx/include/__locale_dir/locale_base_api/musl.h
index b689200baee71f..bf7b849d586342 100644
--- a/libcxx/include/__locale_dir/locale_base_api/musl.h
+++ b/libcxx/include/__locale_dir/locale_base_api/musl.h
@@ -28,17 +28,4 @@ inline _LIBCPP_HIDE_FROM_ABI unsigned long long strtoull_l(const char* __nptr, c
   return ::strtoull(__nptr, __endptr, __base);
 }
 
-inline _LIBCPP_HIDE_FROM_ABI long long wcstoll_l(const wchar_t* __nptr, wchar_t** __endptr, int __base, locale_t) {
-  return ::wcstoll(__nptr, __endptr, __base);
-}
-
-inline _LIBCPP_HIDE_FROM_ABI unsigned long long
-wcstoull_l(const wchar_t* __nptr, wchar_t** __endptr, int __base, locale_t) {
-  return ::wcstoull(__nptr, __endptr, __base);
-}
-
-inline _LIBCPP_HIDE_FROM_ABI long double wcstold_l(const wchar_t* __nptr, wchar_t** __endptr, locale_t) {
-  return ::wcstold(__nptr, __endptr);
-}
-
 #endif // _LIBCPP___LOCALE_LOCALE_BASE_API_MUSL_H
diff --git a/libcxx/include/__locale_dir/locale_base_api/newlib.h b/libcxx/include/__locale_dir/locale_base_api/newlib.h
index 8d030cb73209f8..a8c1cff16e6d80 100644
--- a/libcxx/include/__locale_dir/locale_base_api/newlib.h
+++ b/libcxx/include/__locale_dir/locale_base_api/newlib.h
@@ -9,14 +9,4 @@
 #ifndef _LIBCPP___LOCALE_LOCALE_BASE_API_NEWLIB_H
 #define _LIBCPP___LOCALE_LOCALE_BASE_API_NEWLIB_H
 
-#if defined(_NEWLIB_VERSION)
-
-#  if !defined(__NEWLIB__) || __NEWLIB__ < 2 || __NEWLIB__ == 2 && __NEWLIB_MINOR__ < 5
-#    include <__support/xlocale/__nop_locale_mgmt.h>
-#    include <__support/xlocale/__posix_l_fallback.h>
-#    include <__support/xlocale/__strtonum_fallback.h>
-#  endif
-
-#endif // _NEWLIB_VERSION
-
 #endif // _LIBCPP___LOCALE_LOCALE_BASE_API_NEWLIB_H
diff --git a/libcxx/include/__locale_dir/locale_base_api/openbsd.h b/libcxx/include/__locale_dir/locale_base_api/openbsd.h
index ad999f5dfcad65..0c05d6a0f78874 100644
--- a/libcxx/include/__locale_dir/locale_base_api/openbsd.h
+++ b/libcxx/include/__locale_dir/locale_base_api/openbsd.h
@@ -16,12 +16,4 @@
 #include <ctype.h>
 #include <cwctype>
 
-inline _LIBCPP_HIDE_FROM_ABI long strtol_l(const char* __nptr, char** __endptr, int __base, locale_t) {
-  return ::strtol(__nptr, __endptr, __base);
-}
-
-inline _LIBCPP_HIDE_FROM_ABI unsigned long strtoul_l(const char* __nptr, char** __endptr, int __base, locale_t) {
-  return ::strtoul(__nptr, __endptr, __base);
-}
-
 #endif // _LIBCPP___LOCALE_LOCALE_BASE_API_OPENBSD_H
diff --git a/libcxx/include/__locale_dir/locale_base_api/win32.h b/libcxx/include/__locale_dir/locale_base_api/win32.h
index 5dfacfb9c1ee9d..f66baffb692045 100644
--- a/libcxx/include/__locale_dir/locale_base_api/win32.h
+++ b/libcxx/include/__locale_dir/locale_base_api/win32.h
@@ -225,15 +225,11 @@ _LIBCPP_EXPORTED_FROM_ABI size_t strftime_l(char* ret, size_t n, const char* for
 #  define strftime_l _strftime_l
 #endif
 #define sscanf_l(__s, __l, __f, ...) _sscanf_l(__s, __f, __l, __VA_ARGS__)
-#define sprintf_l(__s, __l, __f, ...) _sprintf_l(__s, __f, __l, __VA_ARGS__)
-#define vsprintf_l(__s, __l, __f, ...) _vsprintf_l(__s, __f, __l, __VA_ARGS__)
-#define vsnprintf_l(__s, __n, __l, __f, ...) _vsnprintf_l(__s, __n, __f, __l, __VA_ARGS__)
 _LIBCPP_EXPORTED_FROM_ABI int snprintf_l(char* __ret, size_t __n, locale_t __loc, const char* __format, ...);
 _LIBCPP_EXPORTED_FROM_ABI int asprintf_l(char** __ret, locale_t __loc, const char* __format, ...);
 _LIBCPP_EXPORTED_FROM_ABI int vasprintf_l(char** __ret, locale_t __loc, const char* __format, va_list __ap);
 
 // not-so-pressing FIXME: use locale to determine blank characters
-inline int isblank_l(int __c, locale_t /*loc*/) { return (__c == ' ' || __c == '\t'); }
 inline int iswblank_l(wint_t __c, locale_t /*loc*/) { return (__c == L' ' || __c == L'\t'); }
 
 #endif // _LIBCPP___LOCALE_LOCALE_BASE_API_WIN32_H
diff --git a/libcxx/include/__support/xlocale/__posix_l_fallback.h b/libcxx/include/__support/xlocale/__posix_l_fallback.h
index 9c3c99e37ecc0c..8a3a6f27f48dde 100644
--- a/libcxx/include/__support/xlocale/__posix_l_fallback.h
+++ b/libcxx/include/__support/xlocale/__posix_l_fallback.h
@@ -29,8 +29,6 @@ inline _LIBCPP_HIDE_FROM_ABI int isalnum_l(int __c, locale_t) { return ::isalnum
 
 inline _LIBCPP_HIDE_FROM_ABI int isalpha_l(int __c, locale_t) { return ::isalpha(__c); }
 
-inline _LIBCPP_HIDE_FROM_ABI int isblank_l(int __c, locale_t) { return ::isblank(__c); }
-
 inline _LIBCPP_HIDE_FROM_ABI int iscntrl_l(int __c, locale_t) { return ::iscntrl(__c); }
 
 inline _LIBCPP_HIDE_FROM_ABI int isdigit_l(int __c, locale_t) { return ::isdigit(__c); }
diff --git a/libcxx/include/__support/xlocale/__strtonum_fallback.h b/libcxx/include/__support/xlocale/__strtonum_fallback.h
index 5dd59500c592b1..b7eef5210ed374 100644
--- a/libcxx/include/__support/xlocale/__strtonum_fallback.h
+++ b/libcxx/include/__support/xlocale/__strtonum_fallback.h
@@ -42,19 +42,4 @@ inline _LIBCPP_HIDE_FROM_ABI unsigned long long strtoull_l(const char* __nptr, c
   return ::strtoull(__nptr, __endptr, __base);
 }
 
-#ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS
-inline _LIBCPP_HIDE_FROM_ABI long long wcstoll_l(const wchar_t* __nptr, wchar_t** __endptr, int __base, locale_t) {
-  return ::wcstoll(__nptr, __endptr, __base);
-}
-
-inline _LIBCPP_HIDE_FROM_ABI unsigned long long
-wcstoull_l(const wchar_t* __nptr, wchar_t** __endptr, int __base, locale_t) {
-  return ::wcstoull(__nptr, __endptr, __base);
-}
-
-inline _LIBCPP_HIDE_FROM_ABI long double wcstold_l(const wchar_t* __nptr, wchar_t** __endptr, locale_t) {
-  return ::wcstold(__nptr, __endptr);
-}
-#endif // _LIBCPP_HAS_NO_WIDE_CHARACTERS
-
 #endif // _LIBCPP___SUPPORT_XLOCALE_STRTONUM_FALLBACK_H