diff --git a/libcxx/include/__support/xlocale/__strtonum_fallback.h b/libcxx/include/__support/xlocale/__strtonum_fallback.h
--- a/libcxx/include/__support/xlocale/__strtonum_fallback.h
+++ b/libcxx/include/__support/xlocale/__strtonum_fallback.h
@@ -19,42 +19,42 @@
 extern "C" {
 #endif
 
-inline _LIBCPP_HIDE_FROM_ABI int float
+inline _LIBCPP_HIDE_FROM_ABI float
 strtof_l(const char *__nptr, char **__endptr, locale_t) {
   return ::strtof(__nptr, __endptr);
 }
 
-inline _LIBCPP_HIDE_FROM_ABI int double
+inline _LIBCPP_HIDE_FROM_ABI double
 strtod_l(const char *__nptr, char **__endptr, locale_t) {
   return ::strtod(__nptr, __endptr);
 }
 
-inline _LIBCPP_HIDE_FROM_ABI int long double
+inline _LIBCPP_HIDE_FROM_ABI long double
 strtold_l(const char *__nptr, char **__endptr, locale_t) {
   return ::strtold(__nptr, __endptr);
 }
 
-inline _LIBCPP_HIDE_FROM_ABI int long long
+inline _LIBCPP_HIDE_FROM_ABI long long
 strtoll_l(const char *__nptr, char **__endptr, int __base, locale_t) {
   return ::strtoll(__nptr, __endptr, __base);
 }
 
-inline _LIBCPP_HIDE_FROM_ABI int unsigned long long
+inline _LIBCPP_HIDE_FROM_ABI unsigned long long
 strtoull_l(const char *__nptr, char **__endptr, int __base, locale_t) {
   return ::strtoull(__nptr, __endptr, __base);
 }
 
-inline _LIBCPP_HIDE_FROM_ABI int long long
+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 int unsigned long long
+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 int long double
+inline _LIBCPP_HIDE_FROM_ABI long double
 wcstold_l(const wchar_t *__nptr, wchar_t **__endptr, locale_t) {
   return ::wcstold(__nptr, __endptr);
 }