llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-clang Author: Aaron Ballman (AaronBallman) <details> <summary>Changes</summary> --- Full diff: https://github.com/llvm/llvm-project/pull/98945.diff 6 Files Affected: - (modified) clang/docs/ReleaseNotes.rst (+7) - (modified) clang/lib/Frontend/InitPreprocessor.cpp (+1-1) - (modified) clang/lib/Headers/stdatomic.h (+6) - (modified) clang/lib/Sema/SemaExpr.cpp (+2) - (added) clang/test/C/C23/n2653.c (+39) - (modified) clang/www/c_status.html (+1-1) ``````````diff diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index a34f109ba21ce..c99493b6ca7dc 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -361,6 +361,13 @@ C23 Feature Support - Added the ``FLT_NORM_MAX``, ``DBL_NORM_MAX``, and ``LDBL_NORM_MAX`` to the freestanding implementation of ``<float.h>`` that ships with Clang. +- Implemented support for + `WG14 N2653 <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2653.htm>`_ + which changes the underlying type of ``u8`` character and string constants + from ``char`` to ``char8_t``, which is a type defined in ``<uchar.h>`` as + being the same type as ``unsigned char``. Also adds support for the type in + ``<stdatomic.h>`` in C23 and later modes. + Non-comprehensive list of changes in this release ------------------------------------------------- diff --git a/clang/lib/Frontend/InitPreprocessor.cpp b/clang/lib/Frontend/InitPreprocessor.cpp index d40d78a38540b..849b97fcf75b8 100644 --- a/clang/lib/Frontend/InitPreprocessor.cpp +++ b/clang/lib/Frontend/InitPreprocessor.cpp @@ -1349,7 +1349,7 @@ static void InitializePredefinedMacros(const TargetInfo &TI, getLockFreeValue(TI.get##Type##Width(), TI)); DEFINE_LOCK_FREE_MACRO(BOOL, Bool); DEFINE_LOCK_FREE_MACRO(CHAR, Char); - if (LangOpts.Char8) + if (LangOpts.Char8 || LangOpts.C23) DEFINE_LOCK_FREE_MACRO(CHAR8_T, Char); // Treat char8_t like char. DEFINE_LOCK_FREE_MACRO(CHAR16_T, Char16); DEFINE_LOCK_FREE_MACRO(CHAR32_T, Char32); diff --git a/clang/lib/Headers/stdatomic.h b/clang/lib/Headers/stdatomic.h index 9c103d98af8c5..2027055f38796 100644 --- a/clang/lib/Headers/stdatomic.h +++ b/clang/lib/Headers/stdatomic.h @@ -35,6 +35,9 @@ extern "C" { #define ATOMIC_BOOL_LOCK_FREE __CLANG_ATOMIC_BOOL_LOCK_FREE #define ATOMIC_CHAR_LOCK_FREE __CLANG_ATOMIC_CHAR_LOCK_FREE +#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L +#define ATOMIC_CHAR8_T_LOCK_FREE __CLANG_ATOMIC_CHAR8_T_LOCK_FREE +#endif #define ATOMIC_CHAR16_T_LOCK_FREE __CLANG_ATOMIC_CHAR16_T_LOCK_FREE #define ATOMIC_CHAR32_T_LOCK_FREE __CLANG_ATOMIC_CHAR32_T_LOCK_FREE #define ATOMIC_WCHAR_T_LOCK_FREE __CLANG_ATOMIC_WCHAR_T_LOCK_FREE @@ -104,6 +107,9 @@ typedef _Atomic(long) atomic_long; typedef _Atomic(unsigned long) atomic_ulong; typedef _Atomic(long long) atomic_llong; typedef _Atomic(unsigned long long) atomic_ullong; +#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 202311L +typedef _Atomic(unsigned char) atomic_char8_t; +#endif typedef _Atomic(uint_least16_t) atomic_char16_t; typedef _Atomic(uint_least32_t) atomic_char32_t; typedef _Atomic(wchar_t) atomic_wchar_t; diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index d6b85cbcaf56b..17a920df66fec 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -2051,6 +2051,8 @@ Sema::ActOnStringLiteral(ArrayRef<Token> StringToks, Scope *UDLScope) { } else if (Literal.isUTF8()) { if (getLangOpts().Char8) CharTy = Context.Char8Ty; + else if (getLangOpts().C23) + CharTy = Context.UnsignedCharTy; Kind = StringLiteralKind::UTF8; } else if (Literal.isUTF16()) { CharTy = Context.Char16Ty; diff --git a/clang/test/C/C23/n2653.c b/clang/test/C/C23/n2653.c new file mode 100644 index 0000000000000..72c8af561db26 --- /dev/null +++ b/clang/test/C/C23/n2653.c @@ -0,0 +1,39 @@ +// RUN: %clang_cc1 -verify=pre-c23 -ffreestanding -std=c17 %s +// RUD: %clang_cc1 -verify -ffreestanding -std=c23 %s + +/* WG14 N2653: Clang 19 + * char8_t: A type for UTF-8 characters and strings + */ + +// expected-no-diagnostics + +#include <stdatomic.h> + +typedef unsigned char char8_t; // in <uchar.h>, which Clang does not provide. + +#if __STDC_VERSION__ >= 202311L + #define LITERAL_TYPE char8_t + #define LITERAL_UNDERLYING_TYPE unsigned char + + // Ensure that char8_t has the same lock-free capabilities as unsigned char. + #if defined(ATOMIC_CHAR8_T_LOCK_FREE) != defined(ATOMIC_CHAR_LOCK_FREE) || \ + ATOMIC_CHAR8_T_LOCK_FREE != ATOMIC_CHAR_LOCK_FREE + #error "invalid char8_t atomic lock free status" + #endif + +#else + #define LITERAL_TYPE char + #define LITERAL_UNDERLYING_TYPE char + + // Ensure we don't define the lock-free status in earlier modes. + #if defined(ATOMIC_CHAR8_T_LOCK_FREE) + #error "ATOMIC_CHAR8_T_LOCK_FREE should not be defined" + #endif +#endif + +// Ensure we get the type of the literal correct. +_Static_assert(_Generic(u8""[0], LITERAL_TYPE : 1, default : 0), ""); +_Static_assert(_Generic(u8""[0], LITERAL_UNDERLYING_TYPE : 1, default : 0), ""); + +// Ensure we have a datatype for atomic operations. +atomic_char8_t val; // pre-c23-error {{unknown type name 'atomic_char8_t'}} diff --git a/clang/www/c_status.html b/clang/www/c_status.html index 669448635837e..3ea70b0163c70 100644 --- a/clang/www/c_status.html +++ b/clang/www/c_status.html @@ -1066,7 +1066,7 @@ <h2 id="c2x">C23 implementation status</h2> <tr> <td>char8_t: A type for UTF-8 characters and strings</td> <td><a href="https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2653.htm";>N2653</a></td> - <td class="none" align="center">No</td> + <td class="unreleased" align="center">Clang 19</td> </tr> <tr> <td>Clarification for max exponent macros-update</td> `````````` </details> https://github.com/llvm/llvm-project/pull/98945 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
