[PATCH] D130058: [Clang] Diagnose ill-formed constant expression when setting a non fixed enum to a value outside the range of the enumeration values

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman accepted this revision.
aaron.ballman added a comment.
This revision is now accepted and ready to land.

LGTM, with some minor nits. Also, please be sure to add a release note.

@erichkeane -- should we update the cxx_dr_status.html page for this? We currently claim Clang 12 for this DR, but it seems like Clang 16 (or 15 if we cherry-pick this) will be the actual release we finished the DR in.



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Comment at: clang/include/clang/Basic/DiagnosticASTKinds.td:370
+def note_constexpr_unscoped_enum_out_of_range : Note<
+  "integer value %0 is outside the valid range of values [%1, %2) for this enumeration type">;
 def err_experimental_clang_interp_failed : Error<
----------------
You should make sure this is flowed to the 80-col limit.


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Comment at: clang/lib/AST/ExprConstant.cpp:13526-13531
+      // This corressponds to [expr.static.cast]p10 which says:
+      // A value of integral or enumeration type can be explicitly converted
+      // to a complete enumeration type ... If the enumeration type does not
+      // have a fixed underlying type, the value is unchanged if the original
+      // value is within the range of the enumeration values ([dcl.enum]), and
+      // otherwise, the behavior is undefined.
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D130058/new/

https://reviews.llvm.org/D130058