P0482R5 char8_t: Standard library support

gcc/cp:

2019-02-19  Tom Honermann  <tom@honermann.net>

	* name-lookup.c (get_std_name_hint): Added u8string as a name hint.

libstdc++:

2019-02-19  Tom Honermann  <tom@honermann.net>

	P0482R5 char8_t: Standard library support
	* config/abi/pre/gnu-versioned-namespace.ver (CXXABI_2.0): Add
	typeinfo symbols for char8_t.
	* config/abi/pre/gnu.ver: Add CXXABI_1.3.12.
	(GLIBCXX_3.4.26): Add symbols for specializations of
	numeric_limits and codecvt that involve char8_t.
	(CXXABI_1.3.12): Add typeinfo symbols for char8_t.
	* include/bits/atomic_base.h: Add atomic_char8_t.
	* include/bits/basic_string.h: Add std::hash<u8string> and
	operator""s(const char8_t*, size_t).
	* include/bits/c++config: Define _GLIBCXX_USE_CHAR8_T and
	__cpp_lib_char8_t.
	* include/bits/char_traits.h: Add char_traits<char8_t>.
	* include/bits/codecvt.h: Add
	codecvt<char16_t, char8_t, mbstate_t>,
	codecvt<char32_t, char8_t, mbstate_t>,
	codecvt_byname<char16_t, char8_t, mbstate_t>, and
	codecvt_byname<char32_t, char8_t, mbstate_t>.
	* include/bits/cpp_type_traits.h: Add __is_integer<char8_t> to
	recognize char8_t as an integral type.
	* include/bits/fs_path.h: (path::__is_encoded_char): Recognize
	char8_t.
	(path::u8string): Return std::u8string when char8_t support is
	enabled.
	(path::generic_u8string): Likewise.
	(path::_S_convert): Handle conversion from char8_t input.
	(path::_S_str_convert): Likewise.
	* include/bits/functional_hash.h: Add hash<char8_t>.
	* include/bits/locale_conv.h (__str_codecvt_out): Add overloads for
	char8_t.
	* include/bits/locale_facets.h (_GLIBCXX_NUM_UNICODE_FACETS): Bump
	for new char8_t specializations.
	* include/bits/localefwd.h: Add missing declarations of
	codecvt<char16_t, char, mbstate_t> and
	codecvt<char32_t, char, mbstate_t>.  Add char8_t declarations
	codecvt<char16_t, char8_t, mbstate_t> and
	codecvt<char32_t, char8_t, mbstate_t>.
	* include/bits/postypes.h: Add u8streampos
	* include/bits/stringfwd.h: Add declarations of
	char_traits<char8_t> and u8string.
	* include/c_global/cstddef: Add __byte_operand<char8_t>.
	* include/experimental/bits/fs_path.h (path::__is_encoded_char):
	Recognize char8_t.
	(path::u8string): Return std::u8string when char8_t support is
	enabled.
	(path::generic_u8string): Likewise.
	(path::_S_convert): Handle conversion from char8_t input.
	(path::_S_str_convert): Likewise.
	* include/experimental/string: Add u8string.
	* include/experimental/string_view: Add u8string_view,
	hash<experimental::u8string_view>, and
	operator""sv(const char8_t*, size_t).
	* include/std/atomic: Add atomic<char8_t> and atomic_char8_t.
	* include/std/charconv (__is_int_to_chars_type): Recognize char8_t
	as a character type.
	* include/std/limits: Add numeric_limits<char8_t>.
	* include/std/string_view: Add u8string_view,
	hash<experimental::u8string_view>, and
	operator""sv(const char8_t*, size_t).
	* include/std/type_traits: Add __is_integral_helper<char8_t>,
	__make_unsigned<char8_t>, and __make_signed<char8_t>.
	* libsupc++/atomic_lockfree_defines.h: Define
	ATOMIC_CHAR8_T_LOCK_FREE.
	* src/c++11/Makefile.am: Compile with -fchar8_t when compiling
	codecvt.cc and limits.cc so that char8_t specializations of
	numeric_limits and codecvt and emitted.
	* src/c++11/Makefile.in: Likewise.
	* src/c++11/codecvt.cc: Define members of
	codecvt<char16_t, char8_t, mbstate_t>,
	codecvt<char32_t, char8_t, mbstate_t>,
	codecvt_byname<char16_t, char8_t, mbstate_t>, and
	codecvt_byname<char32_t, char8_t, mbstate_t>.
	* src/c++11/limits.cc: Define members of
	numeric_limits<char8_t>.
	* src/c++98/Makefile.am: Compile with -fchar8_t when compiling
	locale_init.cc and localename.cc.
	* src/c++98/Makefile.in: Likewise.
	* src/c++98/locale_init.cc: Add initialization for the
	codecvt<char16_t, char8_t, mbstate_t> and
	codecvt<char32_t, char8_t, mbstate_t> facets.
	* src/c++98/localename.cc: Likewise.
	* testsuite/util/testsuite_abi.cc: Validate ABI bump.

From-SVN: r269004

gcc/cp/ChangeLog

@@ -1,3 +1,7 @@
+2019-02-19  Tom Honermann  <tom@honermann.net>
+
+	* name-lookup.c (get_std_name_hint): Added u8string as a name hint.
+
 2019-02-18  Jason Merrill  <jason@redhat.com>
 
 	PR c++/89336 - multiple stores in constexpr stmt.

gcc/cp/name-lookup.c

@@ -5765,6 +5765,7 @@ get_std_name_hint (const char *name)
     {"basic_string", "<string>", cxx98},
     {"string", "<string>", cxx98},
     {"wstring", "<string>", cxx98},
+    {"u8string", "<string>", cxx2a},
     {"u16string", "<string>", cxx11},
     {"u32string", "<string>", cxx11},
     /* <string_view>.  */

libstdc++-v3/ChangeLog

@@ -1,3 +1,88 @@
+2019-02-19  Tom Honermann  <tom@honermann.net>
+
+	P0482R5 char8_t: Standard library support
+	* config/abi/pre/gnu-versioned-namespace.ver (CXXABI_2.0): Add
+	typeinfo symbols for char8_t.
+	* config/abi/pre/gnu.ver: Add CXXABI_1.3.12.
+	(GLIBCXX_3.4.26): Add symbols for specializations of
+	numeric_limits and codecvt that involve char8_t.
+	(CXXABI_1.3.12): Add typeinfo symbols for char8_t.
+	* include/bits/atomic_base.h: Add atomic_char8_t.
+	* include/bits/basic_string.h: Add std::hash<u8string> and
+	operator""s(const char8_t*, size_t).
+	* include/bits/c++config: Define _GLIBCXX_USE_CHAR8_T and
+	__cpp_lib_char8_t.
+	* include/bits/char_traits.h: Add char_traits<char8_t>.
+	* include/bits/codecvt.h: Add
+	codecvt<char16_t, char8_t, mbstate_t>,
+	codecvt<char32_t, char8_t, mbstate_t>,
+	codecvt_byname<char16_t, char8_t, mbstate_t>, and
+	codecvt_byname<char32_t, char8_t, mbstate_t>.
+	* include/bits/cpp_type_traits.h: Add __is_integer<char8_t> to
+	recognize char8_t as an integral type.
+	* include/bits/fs_path.h: (path::__is_encoded_char): Recognize
+	char8_t.
+	(path::u8string): Return std::u8string when char8_t support is
+	enabled.
+	(path::generic_u8string): Likewise.
+	(path::_S_convert): Handle conversion from char8_t input.
+	(path::_S_str_convert): Likewise.
+	* include/bits/functional_hash.h: Add hash<char8_t>.
+	* include/bits/locale_conv.h (__str_codecvt_out): Add overloads for
+	char8_t.
+	* include/bits/locale_facets.h (_GLIBCXX_NUM_UNICODE_FACETS): Bump
+	for new char8_t specializations.
+	* include/bits/localefwd.h: Add missing declarations of
+	codecvt<char16_t, char, mbstate_t> and
+	codecvt<char32_t, char, mbstate_t>.  Add char8_t declarations
+	codecvt<char16_t, char8_t, mbstate_t> and
+	codecvt<char32_t, char8_t, mbstate_t>.
+	* include/bits/postypes.h: Add u8streampos
+	* include/bits/stringfwd.h: Add declarations of
+	char_traits<char8_t> and u8string.
+	* include/c_global/cstddef: Add __byte_operand<char8_t>.
+	* include/experimental/bits/fs_path.h (path::__is_encoded_char):
+	Recognize char8_t.
+	(path::u8string): Return std::u8string when char8_t support is
+	enabled.
+	(path::generic_u8string): Likewise.
+	(path::_S_convert): Handle conversion from char8_t input.
+	(path::_S_str_convert): Likewise.
+	* include/experimental/string: Add u8string.
+	* include/experimental/string_view: Add u8string_view,
+	hash<experimental::u8string_view>, and
+	operator""sv(const char8_t*, size_t).
+	* include/std/atomic: Add atomic<char8_t> and atomic_char8_t.
+	* include/std/charconv (__is_int_to_chars_type): Recognize char8_t
+	as a character type.
+	* include/std/limits: Add numeric_limits<char8_t>.
+	* include/std/string_view: Add u8string_view,
+	hash<experimental::u8string_view>, and
+	operator""sv(const char8_t*, size_t).
+	* include/std/type_traits: Add __is_integral_helper<char8_t>,
+	__make_unsigned<char8_t>, and __make_signed<char8_t>.
+	* libsupc++/atomic_lockfree_defines.h: Define
+	ATOMIC_CHAR8_T_LOCK_FREE.
+	* src/c++11/Makefile.am: Compile with -fchar8_t when compiling
+	codecvt.cc and limits.cc so that char8_t specializations of
+	numeric_limits and codecvt and emitted.
+	* src/c++11/Makefile.in: Likewise.
+	* src/c++11/codecvt.cc: Define members of
+	codecvt<char16_t, char8_t, mbstate_t>,
+	codecvt<char32_t, char8_t, mbstate_t>,
+	codecvt_byname<char16_t, char8_t, mbstate_t>, and
+	codecvt_byname<char32_t, char8_t, mbstate_t>.
+	* src/c++11/limits.cc: Define members of
+	numeric_limits<char8_t>.
+	* src/c++98/Makefile.am: Compile with -fchar8_t when compiling
+	locale_init.cc and localename.cc.
+	* src/c++98/Makefile.in: Likewise.
+	* src/c++98/locale_init.cc: Add initialization for the
+	codecvt<char16_t, char8_t, mbstate_t> and
+	codecvt<char32_t, char8_t, mbstate_t> facets.
+	* src/c++98/localename.cc: Likewise.
+	* testsuite/util/testsuite_abi.cc: Validate ABI bump.
+
 2019-02-18  Wilco Dijkstra  <wdijkstr@arm.com>
 
 	* 27_io/filesystem/operations/all.cc: Add dg-require-filesystem-ts.

libstdc++-v3/config/abi/pre/gnu-versioned-namespace.ver

@@ -301,6 +301,11 @@ CXXABI_2.0 {
     _ZTSN10__cxxabiv120__si_class_type_infoE;
     _ZTSN10__cxxabiv121__vmi_class_type_infoE;
 
+    # typeinfo for char8_t
+    _ZTIDu;
+    _ZTIPDu;
+    _ZTIPKDu;
+
     # typeinfo for char16_t and char32_t
     _ZTIDs;
     _ZTIPDs;

libstdc++-v3/config/abi/pre/gnu.ver

@@ -2244,6 +2244,17 @@ GLIBCXX_3.4.26 {
     # _Sp_make_shared_tag::_S_eq
     _ZNSt19_Sp_make_shared_tag5_S_eqERKSt9type_info;
 
+    # numeric_limits<char8_t>
+    _ZNSt14numeric_limitsIDuE[5-9]*;
+    _ZNSt14numeric_limitsIDuE1[0-7][hirt]*;
+    _ZNSt14numeric_limitsIDuE1[0-7]mi*;
+    _ZNSt14numeric_limitsIDuE1[0-7]max_e*;
+
+    # codecvt<char16_t, char8_t, mbstate_t>, codecvt<char32_t, char8_t, mbstate_t>
+    _ZNKSt7codecvtID[is]Du*;
+    _ZNSt7codecvtID[is]Du*;
+    _ZT[ISV]St7codecvtID[is]Du*E;
+
 } GLIBCXX_3.4.25;
 
 # Symbols in the support library (libsupc++) have their own tag.
@@ -2535,6 +2546,15 @@ CXXABI_1.3.11 {
 
 } CXXABI_1.3.10;
 
+CXXABI_1.3.12 {
+
+    # typeinfo for char8_t
+    _ZTIDu;
+    _ZTIPDu;
+    _ZTIPKDu;
+
+} CXXABI_1.3.11;
+
 # Symbols in the support library (libsupc++) supporting transactional memory.
 CXXABI_TM_1 {
 

libstdc++-v3/include/bits/atomic_base.h

@@ -227,6 +227,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   // atomic_ulong    unsigned long
   // atomic_llong    long long
   // atomic_ullong   unsigned long long
+  // atomic_char8_t  char8_t
   // atomic_char16_t char16_t
   // atomic_char32_t char32_t
   // atomic_wchar_t  wchar_t

libstdc++-v3/include/bits/basic_string.h

@@ -6753,6 +6753,23 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #endif
 #endif /* _GLIBCXX_COMPATIBILITY_CXX0X */
 
+#ifdef _GLIBCXX_USE_CHAR8_T
+  /// std::hash specialization for u8string.
+  template<>
+    struct hash<u8string>
+    : public __hash_base<size_t, u8string>
+    {
+      size_t
+      operator()(const u8string& __s) const noexcept
+      { return std::_Hash_impl::hash(__s.data(),
+                                     __s.length() * sizeof(char8_t)); }
+    };
+
+  template<>
+    struct __is_fast_hash<hash<u8string>> : std::false_type
+    { };
+#endif
+
   /// std::hash specialization for u16string.
   template<>
     struct hash<u16string>
@@ -6805,6 +6822,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     { return basic_string<wchar_t>{__str, __len}; }
 #endif
 
+#ifdef _GLIBCXX_USE_CHAR8_T
+    _GLIBCXX_DEFAULT_ABI_TAG
+    inline basic_string<char8_t>
+    operator""s(const char8_t* __str, size_t __len)
+    { return basic_string<char8_t>{__str, __len}; }
+#endif
+
     _GLIBCXX_DEFAULT_ABI_TAG
     inline basic_string<char16_t>
     operator""s(const char16_t* __str, size_t __len)

libstdc++-v3/include/bits/c++config

@@ -625,6 +625,17 @@ namespace std
 # endif
 #endif
 
+// Unless explicitly specified, enable char8_t extensions only if the core
+// language char8_t feature macro is defined.
+#ifndef _GLIBCXX_USE_CHAR8_T
+# ifdef __cpp_char8_t
+#  define _GLIBCXX_USE_CHAR8_T 1
+# endif
+#endif
+#ifdef _GLIBCXX_USE_CHAR8_T
+# define __cpp_lib_char8_t 201811
+#endif
+
 /* Define if __float128 is supported on this host. */
 #if defined(__FLOAT128__) || defined(__SIZEOF_FLOAT128__)
 #define _GLIBCXX_USE_FLOAT128

libstdc++-v3/include/bits/char_traits.h

@@ -507,6 +507,115 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   };
 #endif //_GLIBCXX_USE_WCHAR_T
 
+#ifdef _GLIBCXX_USE_CHAR8_T
+  template<>
+    struct char_traits<char8_t>
+    {
+      typedef char8_t           char_type;
+      typedef unsigned int      int_type;
+      typedef u8streampos       pos_type;
+      typedef streamoff         off_type;
+      typedef mbstate_t         state_type;
+
+      static _GLIBCXX17_CONSTEXPR void
+      assign(char_type& __c1, const char_type& __c2) _GLIBCXX_NOEXCEPT
+      { __c1 = __c2; }
+
+      static _GLIBCXX_CONSTEXPR bool
+      eq(const char_type& __c1, const char_type& __c2) _GLIBCXX_NOEXCEPT
+      { return __c1 == __c2; }
+
+      static _GLIBCXX_CONSTEXPR bool
+      lt(const char_type& __c1, const char_type& __c2) _GLIBCXX_NOEXCEPT
+      { return __c1 < __c2; }
+
+      static _GLIBCXX17_CONSTEXPR int
+      compare(const char_type* __s1, const char_type* __s2, size_t __n)
+      {
+#if __cplusplus > 201402
+	if (__builtin_constant_p(__n)
+	    && __constant_char_array_p(__s1, __n)
+	    && __constant_char_array_p(__s2, __n))
+	  return __gnu_cxx::char_traits<char_type>::compare(__s1, __s2, __n);
+#endif
+	if (__n == 0)
+	  return 0;
+	return __builtin_memcmp(__s1, __s2, __n);
+      }
+
+      static _GLIBCXX17_CONSTEXPR size_t
+      length(const char_type* __s)
+      {
+#if __cplusplus > 201402
+	if (__constant_string_p(__s))
+	  return __gnu_cxx::char_traits<char_type>::length(__s);
+#endif
+	size_t __i = 0;
+	while (!eq(__s[__i], char_type()))
+	  ++__i;
+	return __i;
+      }
+
+      static _GLIBCXX17_CONSTEXPR const char_type*
+      find(const char_type* __s, size_t __n, const char_type& __a)
+      {
+#if __cplusplus > 201402
+	if (__builtin_constant_p(__n)
+	    && __builtin_constant_p(__a)
+	    && __constant_char_array_p(__s, __n))
+	  return __gnu_cxx::char_traits<char_type>::find(__s, __n, __a);
+#endif
+	if (__n == 0)
+	  return 0;
+	return static_cast<const char_type*>(__builtin_memchr(__s, __a, __n));
+      }
+
+      static char_type*
+      move(char_type* __s1, const char_type* __s2, size_t __n)
+      {
+	if (__n == 0)
+	  return __s1;
+	return static_cast<char_type*>(__builtin_memmove(__s1, __s2, __n));
+      }
+
+      static char_type*
+      copy(char_type* __s1, const char_type* __s2, size_t __n)
+      {
+	if (__n == 0)
+	  return __s1;
+	return static_cast<char_type*>(__builtin_memcpy(__s1, __s2, __n));
+      }
+
+      static char_type*
+      assign(char_type* __s, size_t __n, char_type __a)
+      {
+	if (__n == 0)
+	  return __s;
+	return static_cast<char_type*>(__builtin_memset(__s, __a, __n));
+      }
+
+      static _GLIBCXX_CONSTEXPR char_type
+      to_char_type(const int_type& __c) _GLIBCXX_NOEXCEPT
+      { return char_type(__c); }
+
+      static _GLIBCXX_CONSTEXPR int_type
+      to_int_type(const char_type& __c) _GLIBCXX_NOEXCEPT
+      { return int_type(__c); }
+
+      static _GLIBCXX_CONSTEXPR bool
+      eq_int_type(const int_type& __c1, const int_type& __c2) _GLIBCXX_NOEXCEPT
+      { return __c1 == __c2; }
+
+      static _GLIBCXX_CONSTEXPR int_type
+      eof() _GLIBCXX_NOEXCEPT
+      { return static_cast<int_type>(-1); }
+
+      static _GLIBCXX_CONSTEXPR int_type
+      not_eof(const int_type& __c) _GLIBCXX_NOEXCEPT
+      { return eq_int_type(__c, eof()) ? 0 : __c; }
+    };
+#endif //_GLIBCXX_USE_CHAR8_T
+
 _GLIBCXX_END_NAMESPACE_VERSION
 } // namespace