On 2023-07-05 06:46, Cristian Rodríguez via Libc-alpha wrote:
>    char end_padding[]; --> This is incorrect, since struct rseq contains a
> flexible array it must be the last member..

? struct rseq doesn't contain a flexible array on the master branch, so 
there's no error here.

Perhaps you tried to nest 'struct pthread' inside another struct? If so, 
the C standard doesn't allow that but the attached untested patch should 
be a trivial fix.

Here's the wording in the C23 draft standard section 6.7.2.1 paragraph 
3, which is what GCC is trying to enforce here:

"the last member of a structure with more than one named member may have 
incomplete array type; such a structure (and any union containing, 
possibly recursively, a member that is such a structure) shall not be a 
member of a structure or an element of an array."