[PATCH] D135920: [clang][Sema] Use correct array size for diagnostic

[serge via Phabricator via cfe-commits]

serge-sans-paille added inline comments.


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Comment at: clang/test/SemaCXX/array-bounds.cpp:240
 
-    ((char*)foo)[sizeof(foo)] = '\0';  // expected-warning {{array index 32768 is past the end of the array (which contains 32768 elements)}}
+    ((char*)foo)[sizeof(foo)] = '\0';  // expected-warning {{array index 32768 is past the end of the array (which contains 4096 elements)}}
 
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kees wrote:
> serge-sans-paille wrote:
> > I find this new message quite confusing, because the array index is given in terms of char elements, while the array size is given in terms of double elements. I actually find the original message more consistent to that respect.
> Perhaps show both element count and byte offset?
> 
> `array index $count is $(bytes - end_of_array_in_bytes) past the end of the array (which contains $end_of_array_in_bytes bytes of $array_max_index elements)`
if we have no cast, I find the version without the patch  just fine.

If we have a cast, I suggest we just express the result in bytes, something along those lines (inspired by your suggestion):

    array index $count is $(bytes - end_of_array_in_bytes) bytes past the end of the allocated memory for that array (which contains $end_of_array_in_bytes bytes)


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D135920/new/

https://reviews.llvm.org/D135920