https://github.com/philnik777 updated https://github.com/llvm/llvm-project/pull/223440
>From 83761e7d3c0927451bff581eb2ed97e3f18a73d0 Mon Sep 17 00:00:00 2001 From: Nikolas Klauser <[email protected]> Date: Mon, 14 Sep 2026 17:26:53 +0200 Subject: [PATCH 1/2] [Clang] Document when to use ExtWarn and Extension --- clang/docs/InternalsManual.md | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/clang/docs/InternalsManual.md b/clang/docs/InternalsManual.md index 0d9ee745927aa..79b73dbf36a2a 100644 --- a/clang/docs/InternalsManual.md +++ b/clang/docs/InternalsManual.md @@ -114,6 +114,18 @@ severe that error recovery won't be able to recover sensibly from them (thus spewing a ton of bogus errors). One example of this class of error is failure to `#include` a file. +##### Extension vs ExtWarn + +The `Extension` and `ExtWarn` are very closely related. Deciding when to use +which one can be difficult. `ExtWarn` should be used in cases an extension is +diagnosed and one of the following applies (or another good reason is stated): +- the extension is likely to be used incorrectly (e.g. `-Wvla`) +- the diagnosed code is likely wrong (e.g. `-Wmain`) +- the extension is likely surprising in some cases (e.g. `SFINAEFailure`) +- the extension is deprecated (e.g. `-Wauto-storage-class`) + +`Extension` should be used in all other circumstances. + #### Diagnostic Wording The wording used for a diagnostic is critical because it is the only way for a >From 2cbc4babfb98b66868e9d171be1a29bfb400fcc5 Mon Sep 17 00:00:00 2001 From: Nikolas Klauser <[email protected]> Date: Mon, 21 Sep 2026 12:27:58 +0200 Subject: [PATCH 2/2] Update clang/docs/InternalsManual.md Co-authored-by: Ambrose Leeb <[email protected]> --- clang/docs/InternalsManual.md | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/clang/docs/InternalsManual.md b/clang/docs/InternalsManual.md index 79b73dbf36a2a..c2925563aa388 100644 --- a/clang/docs/InternalsManual.md +++ b/clang/docs/InternalsManual.md @@ -116,13 +116,12 @@ to `#include` a file. ##### Extension vs ExtWarn -The `Extension` and `ExtWarn` are very closely related. Deciding when to use -which one can be difficult. `ExtWarn` should be used in cases an extension is -diagnosed and one of the following applies (or another good reason is stated): -- the extension is likely to be used incorrectly (e.g. `-Wvla`) -- the diagnosed code is likely wrong (e.g. `-Wmain`) -- the extension is likely surprising in some cases (e.g. `SFINAEFailure`) -- the extension is deprecated (e.g. `-Wauto-storage-class`) +Deciding whether to use `Extension` or `ExtWarn` can be difficult. +`ExtWarn` should be used if one of the following applies (or another good reason is stated): +- the extension is likely to be used incorrectly (e.g. `-Wvla`); +- the diagnosed code is likely wrong (e.g. `-Wmain`); +- the extension is likely surprising in some cases (e.g. `SFINAEFailure`); +- the extension is deprecated (e.g. `-Wauto-storage-class`). `Extension` should be used in all other circumstances. _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
