[PATCH v3] Fix POSIX compliance: Make blkcnt_t and blksize_t signed on alpha

[Joseph Myers]

On Sun, 23 Nov 2025, Osama Abdelkader wrote:

> POSIX requires that blkcnt_t and blksize_t are signed integer types.
> On alpha, these were incorrectly defined as unsigned types.
> This change makes them signed to match:
> - POSIX requirements
> - All other architectures in glibc
> 
> Fixes #33355

How has this been tested?  I'd have expected c++-types-check to fail 
because it verified the mangling of various types, including these ones, 
hasn't accidentally changed.

-- 
Joseph S. Myers
josmyers@redhat.com