[PATCH] D37042: Teach clang to tolerate the 'p = nullptr + n' idiom used by glibc

[Eli Friedman via Phabricator via cfe-commits]

efriedma added inline comments.


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Comment at: include/clang/Basic/DiagnosticSemaKinds.td:6031
   InGroup<PointerArith>;
+def ext_gnu_null_ptr_arith : Extension<
+  "arithmetic on a null pointer treated as a cast from integer to pointer is a GNU extension">,
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andrew.w.kaylor wrote:
> efriedma wrote:
> > "extension" isn't really right here; this shouldn't be an error in -pedantic-errors mode.  Probably best to just stick this into the NullPointerArithmetic, like the other new warning.
> So how should a word the warning?  Just this:
> 
> "arithmetic on a null pointer treated as a cast from integer to pointer"?
That wasn't what I meant; the current wording is fine. I meant this should be something like `def warn_gnu_null_ptr_arith : Warning<`.


https://reviews.llvm.org/D37042