[PATCH] libstdc++: Do not assume existence of char8_t codecvt facet

[Joseph Faulls]

It is not required that codecvt<char8_t, char, mbstate_t> facet be supported by
the locale, nor is it added as part of the default locale. This can lead to
dangerous behaviour when static_cast.

libstdc++-v3/ChangeLog:

        * include/bits/locale_classes.tcc: Remove check.
---
libstdc++-v3/include/bits/locale_classes.tcc | 3 ---
1 file changed, 3 deletions(-)

diff --git a/libstdc++-v3/include/bits/locale_classes.tcc 
b/libstdc++-v3/include/bits/locale_classes.tcc
index 94838cd7796..2351dd5bcfb 100644
--- a/libstdc++-v3/include/bits/locale_classes.tcc
+++ b/libstdc++-v3/include/bits/locale_classes.tcc
@@ -129,9 +129,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       _GLIBCXX_STD_FACET(time_put<wchar_t>);
       _GLIBCXX_STD_FACET(messages<wchar_t>);
#endif
-#ifdef _GLIBCXX_USE_CHAR8_T
-      _GLIBCXX_STD_FACET(codecvt<char8_t, char, mbstate_t>);
-#endif
#if __cplusplus >= 201103L
       _GLIBCXX_STD_FACET(codecvt<char16_t, char, mbstate_t>);
       _GLIBCXX_STD_FACET(codecvt<char32_t, char, mbstate_t>);
--
2.34.1