https://github.com/nfedotenko updated https://github.com/llvm/llvm-project/pull/236263
>From f6c28840c379dcd008a61e3f97ed530929886b78 Mon Sep 17 00:00:00 2001 From: Nikolay Fedotenko <[email protected]> Date: Wed, 28 Oct 2026 02:30:57 +0400 Subject: [PATCH 1/3] [C++26] Define the __cpp_pp_embed feature-test macro Now that the known #embed bugs affecting valid code are fixed -- the multi-byte braced-list miscompile (#222796, fixed by #231938) and the parameter-lexing assertion (#212075, fixed by #235934) -- define __cpp_pp_embed to 202502L. It is defined in all C++ language modes, like the other C++26 features Clang supports as extensions in earlier modes. The C++ status page entry for P1967R14 is updated accordingly. Part of #127610. --- clang/docs/ReleaseNotes.md | 4 ++-- clang/lib/Frontend/InitPreprocessor.cpp | 1 + clang/test/Lexer/cxx-features.cpp | 4 ++++ clang/test/Preprocessor/embed_feature_test.cpp | 10 ++++++++++ clang/www/cxx_status.html | 12 ++++++------ 5 files changed, 23 insertions(+), 8 deletions(-) diff --git a/clang/docs/ReleaseNotes.md b/clang/docs/ReleaseNotes.md index c5532359ef7af8..1770aae51b053a 100644 --- a/clang/docs/ReleaseNotes.md +++ b/clang/docs/ReleaseNotes.md @@ -235,8 +235,8 @@ documentation](CIR/index.md) for more information regarding ClangIR's status and now diagnosed as a C++26 extension under `-Wc++26-extensions` (previously it was diagnosed as a Clang extension under `-Wc23-extensions`), and a new `-Wpre-c++26-compat` warning is available in C++26 mode. The - `__cpp_pp_embed` feature-test macro is not yet defined because of known - issues in the implementation. + `__cpp_pp_embed` feature-test macro is now defined, following the fixes for + the known initialization bugs with multi-byte `#embed` in braced lists. - Added `__builtin_type_order` for compatibility with GCC as part of the implementation of [P2830R10](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2025/p2830r10.html) (Constexpr Type Ordering). diff --git a/clang/lib/Frontend/InitPreprocessor.cpp b/clang/lib/Frontend/InitPreprocessor.cpp index 784ff9951a25ad..4f2a2a1bd28b79 100644 --- a/clang/lib/Frontend/InitPreprocessor.cpp +++ b/clang/lib/Frontend/InitPreprocessor.cpp @@ -765,6 +765,7 @@ static void InitializeCPlusPlusFeatureTestMacros(const LangOptions &LangOpts, Builder.defineMacro("__cpp_deleted_function", "202403L"); Builder.defineMacro("__cpp_variadic_friend", "202403L"); Builder.defineMacro("__cpp_trivial_relocatability", "202502L"); + Builder.defineMacro("__cpp_pp_embed", "202502L"); if (LangOpts.Char8) Builder.defineMacro("__cpp_char8_t", "202207L"); diff --git a/clang/test/Lexer/cxx-features.cpp b/clang/test/Lexer/cxx-features.cpp index b505f18dff14fe..f920ad64ba056b 100644 --- a/clang/test/Lexer/cxx-features.cpp +++ b/clang/test/Lexer/cxx-features.cpp @@ -54,6 +54,10 @@ #error "wrong value for __cpp_placeholder_variables" #endif +#if check(pp_embed, 202502, 202502, 202502, 202502, 202502, 202502, 202502) +#error "wrong value for __cpp_pp_embed" +#endif + #if check(trivial_relocatability, 202502, 202502, 202502, 202502, 202502, 202502, 202502) #error "wrong value for __cpp_trivial_relocatability" #endif diff --git a/clang/test/Preprocessor/embed_feature_test.cpp b/clang/test/Preprocessor/embed_feature_test.cpp index 2648804132599b..2b44586012a168 100644 --- a/clang/test/Preprocessor/embed_feature_test.cpp +++ b/clang/test/Preprocessor/embed_feature_test.cpp @@ -5,3 +5,13 @@ #if !defined(__has_embed) #error 1 #endif + +#ifdef __cplusplus +#if __cpp_pp_embed != 202502L +#error 2 +#endif +#else +#ifdef __cpp_pp_embed +#error 3 +#endif +#endif diff --git a/clang/www/cxx_status.html b/clang/www/cxx_status.html index 67a73771b05a6c..540f3d10c8ce7b 100755 --- a/clang/www/cxx_status.html +++ b/clang/www/cxx_status.html @@ -400,13 +400,13 @@ <h2 id="cxx26">C++2c implementation status</h2> <tr> <td><pre>#embed</pre></td> <td><a href="https://wg21.link/P1967";>P1967R14</a></td> - <td class="partial" align="center"> + <td class="full" align="center"> <details> - <summary>Clang 24 (Partial)</summary> - The directive and its parameters are supported since Clang 19. A - multi-byte <tt>#embed</tt> in a braced initializer list that initializes - a non-aggregate object is not yet handled correctly in some contexts, so - the <tt>__cpp_pp_embed</tt> feature-test macro is not defined yet. + <summary>Clang 24</summary> + The directive and its parameters are supported since Clang 19; Clang 24 + fixed the remaining initialization bugs with multi-byte <tt>#embed</tt> + in braced lists and defines the <tt>__cpp_pp_embed</tt> feature-test + macro. </details> </td> </tr> >From 4d07e3851021969e3310b86d4c53f7f3b3ef2b3f Mon Sep 17 00:00:00 2001 From: Nikolay Fedotenko <[email protected]> Date: Thu, 29 Oct 2026 23:35:45 +0400 Subject: [PATCH 2/3] Address review: unreleased status class, shorter notes, back-ported extensions table --- clang/docs/LanguageExtensions.md | 1 + clang/docs/ReleaseNotes.md | 3 +-- clang/www/cxx_status.html | 10 +--------- 3 files changed, 3 insertions(+), 11 deletions(-) diff --git a/clang/docs/LanguageExtensions.md b/clang/docs/LanguageExtensions.md index 3db8d083c40756..7b930e2ac0a534 100644 --- a/clang/docs/LanguageExtensions.md +++ b/clang/docs/LanguageExtensions.md @@ -1782,6 +1782,7 @@ More information can be found [here](Modules.md). | `= delete ("should have a reason");` | \_\_cpp_deleted_function | C++26 | C++03 | | Variadic Friends | \_\_cpp_variadic_friend | C++26 | C++03 | | Trivial Relocatability | \_\_cpp_trivial_relocatability | C++26 | C++03 | +| `#embed` | \_\_cpp_pp_embed | C++26 | C++03 | |``auto()`` cast | \_\_cpp_auto_cast | C++26 | C++03 | | Pack Indexing for Template Names | \_\_cpp_pack_indexing >= 202606L | C++2d | C++03 | | Designated initializers (N494) | | C99 | C89 | diff --git a/clang/docs/ReleaseNotes.md b/clang/docs/ReleaseNotes.md index 1770aae51b053a..e6d039f73e7093 100644 --- a/clang/docs/ReleaseNotes.md +++ b/clang/docs/ReleaseNotes.md @@ -235,8 +235,7 @@ documentation](CIR/index.md) for more information regarding ClangIR's status and now diagnosed as a C++26 extension under `-Wc++26-extensions` (previously it was diagnosed as a Clang extension under `-Wc23-extensions`), and a new `-Wpre-c++26-compat` warning is available in C++26 mode. The - `__cpp_pp_embed` feature-test macro is now defined, following the fixes for - the known initialization bugs with multi-byte `#embed` in braced lists. + `__cpp_pp_embed` feature-test macro is now defined. - Added `__builtin_type_order` for compatibility with GCC as part of the implementation of [P2830R10](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2025/p2830r10.html) (Constexpr Type Ordering). diff --git a/clang/www/cxx_status.html b/clang/www/cxx_status.html index 540f3d10c8ce7b..aacb26dfeddc80 100755 --- a/clang/www/cxx_status.html +++ b/clang/www/cxx_status.html @@ -400,15 +400,7 @@ <h2 id="cxx26">C++2c implementation status</h2> <tr> <td><pre>#embed</pre></td> <td><a href="https://wg21.link/P1967";>P1967R14</a></td> - <td class="full" align="center"> - <details> - <summary>Clang 24</summary> - The directive and its parameters are supported since Clang 19; Clang 24 - fixed the remaining initialization bugs with multi-byte <tt>#embed</tt> - in braced lists and defines the <tt>__cpp_pp_embed</tt> feature-test - macro. - </details> - </td> + <td class="unreleased" align="center">Clang 24</td> </tr> <!-- Bulgaria, Spring 2025 --> <tr> >From 6b4eb835e0e98b9037cbc9dcfb298ec900d18896 Mon Sep 17 00:00:00 2001 From: Nikolay Fedotenko <[email protected]> Date: Fri, 30 Oct 2026 11:51:56 +0400 Subject: [PATCH 3/3] Drop C++ from the N3017 #embed backported-to entry, now covered by the C++26 row --- clang/docs/LanguageExtensions.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/clang/docs/LanguageExtensions.md b/clang/docs/LanguageExtensions.md index 7b930e2ac0a534..6c1eddb4bc863b 100644 --- a/clang/docs/LanguageExtensions.md +++ b/clang/docs/LanguageExtensions.md @@ -1808,7 +1808,7 @@ More information can be found [here](Modules.md). | `_Thread_local` (N1364) | | C11 | C89, C++ | | Array & element qualification (N2607) | | C23 | C89 | | Attributes (N2335) | | C23 | C89 | -| `#embed` (N3017) | | C23 | C89, C++ | +| `#embed` (N3017) | | C23 | C89 | | Enum with fixed underlying type (N3030) | | C23 | C89 | | `#warning` (N2686) | | C23 | C89 | | `_BitInt` (N3035) | | C23 | C89, C++ | _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
