On Mon, Dec 10, 2018 at 04:30:11PM -0700, Martin Sebor wrote: > Some of my testing exposed a minor problem in GCC 9's validation > of the type of function parameters referred to by attribute > positional arguments. Whereas GCC 8 accepts all C integer types, > including enumerated types, such as: > > enum AllocAlign { Align16 = 16, Align32 = 32 }; > > __attribute__ ((alloc_align (1))) void* > alloc (size_t, enum AllocAlign) > > GCC 9 only accepts signed and unsigned integer types. This change > (introduced by myself) was unintentional, and a fix for it is in > the attached trivial patch. I plan to commit it without approval > in the next day or so unless any concerns or suggestions come up.
There is nothing obvious about this, so please don't commit it without approval. GCC 8 and older used to accept even float or void * or struct arguments and just ignored them. I think we need to discuss what types we want to allow without warnings and what we should warn. As I wrote in the PR, I believe e.g. using alloc_align/alloc_size with bool/_Bool is just a clear bug, you can store 0 or 1 in there, but e.g. alignment 0 doesn't make sense. Enums are on the border line, I'll defer to C/C++ maintainers whether we want to include that or not. Jakub