void added inline comments.
================ 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)}} ---------------- serge-sans-paille wrote: > 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) I so far have this. It looks not too bad even for the non-cast. Thoughts? ``` $ cat ab.c void test_pr10771() { double foo[4096]; // expected-note {{array 'foo' declared here}} ((char*)foo)[sizeof(foo)] = '\0'; // expected-warning {{array index 32768 is past the end of the array (which contains 4096 elements of type 'double[4096])}} foo[4098] = '\0'; // expected-warning {{array index 32768 is past the end of the array (which contains 4096 elements of type 'double[4096])}} } $ clang++ -x c++ -o /dev/null -S -std=c++14 ~/llvm/ab.c /home/morbo/llvm/ab.c:4:13: warning: array index 32768 is 0 bytes past the end of the array (that has type 'double[4096]') [-Warray-bounds] ((char*)foo)[sizeof(foo)] = '\0'; // expected-warning {{array index 32768 is past the end of the array (which contains 4096 elements of type 'double[4096])}} ^ ~~~~~~~~~~~ /home/morbo/llvm/ab.c:2:5: note: array 'foo' declared here double foo[4096]; // expected-note {{array 'foo' declared here}} ^ /home/morbo/llvm/ab.c:5:5: warning: array index 4098 is 16 bytes past the end of the array (that has type 'double[4096]') [-Warray-bounds] foo[4098] = '\0'; // expected-warning {{array index 32768 is past the end of the array (which contains 4096 elements of type 'double[4096])}} ^ ~~~~ /home/morbo/llvm/ab.c:2:5: note: array 'foo' declared here double foo[4096]; // expected-note {{array 'foo' declared here}} ^ 2 warnings generated. ``` Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D135920/new/ https://reviews.llvm.org/D135920 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits