https://gcc.gnu.org/g:16491e137c47ad36f9d73f070978841f1e8ca95d
commit r15-3935-g16491e137c47ad36f9d73f070978841f1e8ca95d
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Fri Sep 27 15:53:04 2024 +0100
libstdc++: Refactor experimental::filesystem::path string conversions
I noticed a -Wc++17-extensions warning due to use of if-constexpr in
std::experimental::filesystem::path, which was not protected by
diagnostic pragmas to disable the warning.
While adding the pragmas I noticed that other places in the same file
use tag dispatching and multiple overloads instead of if-constexpr.
Since we're already using it in that file, we might as well just use it
everywhere.
libstdc++-v3/ChangeLog:
* include/experimental/bits/fs_path.h (path::_Cvt): Refactor to
use if-constexpr.
(path::string(const Allocator&)): Likewise.
Diff:
---
libstdc++-v3/include/experimental/bits/fs_path.h | 137 +++++++++--------------
1 file changed, 53 insertions(+), 84 deletions(-)
diff --git a/libstdc++-v3/include/experimental/bits/fs_path.h
b/libstdc++-v3/include/experimental/bits/fs_path.h
index 5008e26af8db..a504aa2492cc 100644
--- a/libstdc++-v3/include/experimental/bits/fs_path.h
+++ b/libstdc++-v3/include/experimental/bits/fs_path.h
@@ -775,60 +775,38 @@ namespace __detail
__codecvt_utf8_to_wchar,
__codecvt_utf8_to_utfNN>;
-#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
-#ifdef _GLIBCXX_USE_CHAR8_T
- static string_type
- _S_wconvert(const char8_t* __f, const char8_t* __l, const char8_t*)
- {
- const char* __f2 = (const char*)__f;
- const char* __l2 = (const char*)__l;
- std::wstring __wstr;
- std::codecvt_utf8_utf16<wchar_t> __wcvt;
- if (__str_codecvt_in_all(__f2, __l2, __wstr, __wcvt))
- return __wstr;
- }
-#endif
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
static string_type
- _S_wconvert(const char* __f, const char* __l, const char*)
- {
- std::codecvt_utf8_utf16<wchar_t> __cvt;
- std::wstring __wstr;
- if (__str_codecvt_in_all(__f, __l, __wstr, __cvt))
- return __wstr;
- _GLIBCXX_THROW_OR_ABORT(filesystem_error(
- "Cannot convert character sequence",
- std::make_error_code(errc::illegal_byte_sequence)));
- }
-
- static string_type
- _S_wconvert(const _CharT* __f, const _CharT* __l, const void*)
+ _S_convert(const _CharT* __f, const _CharT* __l)
{
- __codecvt_utf8_to_wide __cvt;
- std::string __str;
- if (__str_codecvt_out_all(__f, __l, __str, __cvt))
+#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
+ if constexpr (is_same<_CharT, char>::value)
{
- const char* __f2 = __str.data();
- const char* __l2 = __f2 + __str.size();
- std::codecvt_utf8_utf16<wchar_t> __wcvt;
+ std::codecvt_utf8_utf16<wchar_t> __cvt;
std::wstring __wstr;
- if (__str_codecvt_in_all(__f2, __l2, __wstr, __wcvt))
+ // Convert char (assumed to be UTF-8) to wchar_t (UTF-16).
+ if (__str_codecvt_in_all(__f, __l, __wstr, __cvt))
return __wstr;
}
+#ifdef _GLIBCXX_USE_CHAR8_T
+ else if constexpr (is_same<_CharT, char8_t>::value)
+ return _S_convert((const char*)__f, (const char*)__l);
+#endif
+ else
+ {
+ // Convert from _CharT to char first:
+ __codecvt_utf8_to_utfNN __cvt;
+ std::string __str;
+ if (__str_codecvt_out_all(__f, __l, __str, __cvt))
+ // Then convert char to wchar_t:
+ return _S_convert(__str.c_str(), __str.c_str() + __str.size());
+ }
_GLIBCXX_THROW_OR_ABORT(filesystem_error(
"Cannot convert character sequence",
std::make_error_code(errc::illegal_byte_sequence)));
- }
-
- static string_type
- _S_convert(const _CharT* __f, const _CharT* __l)
- {
- return _S_wconvert(__f, __l, (const _CharT*)nullptr);
- }
-#else
- static string_type
- _S_convert(const _CharT* __f, const _CharT* __l)
- {
+#else // ! WINDOWS
#ifdef _GLIBCXX_USE_CHAR8_T
if constexpr (is_same<_CharT, char8_t>::value)
return string_type(__f, __l);
@@ -843,8 +821,9 @@ namespace __detail
"Cannot convert character sequence",
std::make_error_code(errc::illegal_byte_sequence)));
}
+#endif // ! WINDOWS
}
-#endif
+#pragma GCC diagnostic pop
static string_type
_S_convert(_CharT* __f, _CharT* __l)
@@ -1038,66 +1017,55 @@ namespace __detail
std::swap(_M_type, __rhs._M_type);
}
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wc++17-extensions" // if constexpr
template<typename _CharT, typename _Traits, typename _Allocator>
inline std::basic_string<_CharT, _Traits, _Allocator>
path::string(const _Allocator& __a) const
{
- if _GLIBCXX17_CONSTEXPR (is_same<_CharT, value_type>::value)
- return { _M_pathname.begin(), _M_pathname.end(), __a };
-
using _WString = basic_string<_CharT, _Traits, _Allocator>;
const value_type* __first = _M_pathname.data();
const value_type* __last = __first + _M_pathname.size();
+ if constexpr (is_same<_CharT, value_type>::value)
+ return _WString(__first, __last, __a);
#ifdef _GLIBCXX_FILESYSTEM_IS_WINDOWS
- using _CharAlloc = __alloc_rebind<_Allocator, char>;
- using _String = basic_string<char, char_traits<char>, _CharAlloc>;
-
- // First convert native string from UTF-16 to to UTF-8.
- // XXX This assumes that the execution wide-character set is UTF-16.
- codecvt_utf8_utf16<value_type> __cvt;
- _String __u8str{_CharAlloc{__a}};
- if (__str_codecvt_out_all(__first, __last, __u8str, __cvt))
+ else
{
- struct
- {
- const _String*
- operator()(const _String& __from, _String&, true_type)
- { return std::__addressof(__from); }
-
- _WString*
- operator()(const _String& __from, _WString& __to, false_type)
+ using _CharAlloc = __alloc_rebind<_Allocator, char>;
+ using _String = basic_string<char, char_traits<char>, _CharAlloc>;
+
+ // First convert native string from UTF-16 to to UTF-8.
+ // XXX This assumes that the execution wide-character set is UTF-16.
+ codecvt_utf8_utf16<value_type> __cvt;
+ _String __u8str{_CharAlloc{__a}};
+ if (__str_codecvt_out_all(__first, __last, __u8str, __cvt))
{
+ if constexpr (is_same<_CharT, char>::value)
+ return __u8str;
#ifdef _GLIBCXX_USE_CHAR8_T
- if constexpr (is_same<_CharT, char8_t>::value)
- {
- __to.assign(__from.begin(), __from.end());
- return std::__addressof(__to);
- }
- else
+ else if constexpr (is_same<_CharT, char8_t>::value)
+ return _WString(__u8str.begin(), __u8str.end(), __a);
#endif
- {
+ else
+ {
+ _WString __wstr(__a);
// Convert UTF-8 to char16_t or char32_t string.
typename path::_Cvt<_CharT>::__codecvt_utf8_to_wide __cvt;
- const char* __f = __from.data();
- const char* __l = __f + __from.size();
- if (__str_codecvt_in_all(__f, __l, __to, __cvt))
- return std::__addressof(__to);
- }
- return nullptr;
+ const char* __f = __u8str.data();
+ const char* __l = __f + __u8str.size();
+ if (__str_codecvt_in_all(__f, __l, __wstr, __cvt))
+ return __wstr;
+ }
}
- } __dispatch;
- _WString __wstr(__a);
- if (auto* __p = __dispatch(__u8str, __wstr, is_same<_CharT, char>{}))
- return *__p;
}
#else // ! Windows
#ifdef _GLIBCXX_USE_CHAR8_T
- if constexpr (is_same<_CharT, char8_t>::value)
- return _WString(__first, __last, __a);
- else
+ else if constexpr (is_same<_CharT, char8_t>::value)
+ return _WString(__first, __last, __a);
#endif
+ else
{
typename path::_Cvt<_CharT>::__codecvt_utf8_to_wide __cvt;
_WString __wstr(__a);
@@ -1109,6 +1077,7 @@ namespace __detail
"Cannot convert character sequence",
std::make_error_code(errc::illegal_byte_sequence)));
}
+#pragma GCC diagnostic pop
inline std::string
path::string() const { return string<char>(); }
