llvm-project

9ae3bce1 - [Clang][counted_by] Add support for 'counted_by' on struct pointers (#137250)

[Clang][counted_by] Add support for 'counted_by' on struct pointers (#137250) The 'counted_by' attribute is now available for pointers in structs. It generates code for sanity checks as well as __builtin_dynamic_object_size() calculations. For example: struct annotated_ptr { int count; char *buf __attribute__((counted_by(count))); }; If the pointer's type is 'void *', use the 'sized_by' attribute, which works similarly to 'counted_by', but can handle the 'void' base type: struct annotated_ptr { int count; void *buf __attribute__((sized_by(count))); }; If the 'count' field member occurs after the pointer, use the '-fexperimental-late-parse-attributes' flag during compilation. Note that 'counted_by' cannot be applied to a pointer to an incomplete type, because the size isn't known. struct foo; struct annotated_ptr { int count; struct foo *buf __attribute__((counted_by(count))); /* invalid */ }; Signed-off-by: Bill Wendling <morbo@google.com>