[PATCH] D19689: Add Subjects to NoDebugAttr [NFC]

[Aaron Ballman via cfe-commits]

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

This turns out to be a bit of a mess: Alias and NoDebug use the same diagnostic kind text, neither of which match the actual subject list. Alias doesn't appertain to an obj-c method or property. NoDebug doesn't appertain to an obj-c property. The diagnostic text for that diagnostic kind doesn't match the subject list it is describing in either case. And the diagnostic text talks about "global variables" when what it really means are "variables that have global *storage*" and so static storage duration is a bit more accurate than "global variable" which implies that the following should diagnose:

  void f() {
    static int i __attribute__((nodebug));
  }

I have a WIP patch (http://reviews.llvm.org/D18768) that will hopefully make this situation better. Your current changes will add a bit of overhead to my refactoring, but it's a drop in the bucket compared to the other diagnostic wording changes, so I'm not overly concerned. I think the patch LGTM despite my comments.


================
Comment at: include/clang/Basic/Attr.td:977
@@ -976,1 +976,3 @@
+  let Subjects = SubjectList<[FunctionLike, ObjCMethod, GlobalVar], WarnDiag,
+                              "ExpectedFunctionGlobalVarMethodOrProperty">;
   let Documentation = [NoDebugDocs];
----------------
It's really strange that the diagnostic kind is `ExpectedFunctionGlobalVarMethodOrProperty` but the subject list does not have objective-c properties. It's even more strange that this diagnostic kind corresponds to the diagnostic text "functions and global variables" without mention of objective-c methods or properties. I see that the Alias attribute suffers from this same discombobulation.

================
Comment at: test/Sema/attr-nodebug.c:6
@@ -5,3 +5,3 @@
 void b() {
-  int b __attribute__((nodebug)); // expected-warning {{'nodebug' only applies to variables with static storage duration and functions}}
+  int b __attribute__((nodebug)); // expected-warning {{'nodebug' attribute only applies to functions and global variables}}
 }
----------------
Global variables is a misnomer though since this really applies to variables with static storage duration (including local variables).


http://reviews.llvm.org/D19689