[clang][doc] Document C2y flags (#138521)

tambry · web-flow · commit d66dbd6931a4 · 2025-05-06T11:19:57.000+03:00
As discussed at llvm/llvm-project#138459 (comment)
diff --git a/clang/docs/CommandGuide/clang.rst b/clang/docs/CommandGuide/clang.rst
@@ -155,6 +155,14 @@ Language Selection and Mode Options
 
    ISO C 2023 with GNU extensions
 
+  | ``c2y``
+
+   ISO C 202y
+
+  | ``gnu2y``
+
+   ISO C 202y with GNU extensions
+
  The default C language standard is ``gnu17``, except on PS4, where it is
  ``gnu99``.
 
diff --git a/clang/include/clang/Basic/LangStandards.def b/clang/include/clang/Basic/LangStandards.def
@@ -105,7 +105,7 @@ LANGSTANDARD(c2y, "c2y",
 LANGSTANDARD(gnu2y, "gnu2y",
              C, "Working Draft for ISO C2y with GNU extensions",
              LineComment | C99 | C11 | C17 | C23 | C2y | Digraphs | GNUMode | HexFloat)
-
+// TODO: Add the iso9899:202y alias once ISO publishes the standard.
 
 // C++ modes
 LANGSTANDARD(cxx98, "c++98",
