Fix 32-bit SSIZE_MAX

POSIX requires that SSIZE_MAX have the same type as ssize_t, but
on 32-bit, we were defining it as a long even though ssize_t
resolves to an int.  It also requires that SSIZE_MAX be usable
via preprocessor #if, so we can't cheat and use a cast.

If this were newlib, I'd have had to hack _intsup.h to probe the
qualities of size_t (via gcc's __SIZE_TYPE__), similar to how we
already probe the qualities of int8_t and friends, then cross our
fingers that ssize_t happens to have the same rank (most systems
do, but POSIX permits a system where they differ such as size_t
being long while ssize_t is int).  Unfortunately gcc gives us
neither __SSIZE_TYPE__ nor __SSIZE_MAX__.  On the other hand, our
limits.h is specific to cygwin, so we can just shortcut to the
correct results rather than being generic to all possible ABI.

Signed-off-by: Eric Blake <eblake@redhat.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/winsup/cygwin/release/2.5.3 b/winsup/cygwin/release/2.5.3
index a27106bff..0a273964a 100644
--- a/winsup/cygwin/release/2.5.3
+++ b/winsup/cygwin/release/2.5.3
@@ -10,6 +10,9 @@ What changed:
 - Raise number of supported partitions per disk (for raw access) to 63.
   Addresses: https://cygwin.com/ml/cygwin/2016-06/msg00136.html
 
+- Fix definition of SSIZE_MAX on 32-bit systems.
+  Addresses: https://cygwin.com/ml/cygwin/2016-07/msg00179.html
+
 
 Bug Fixes
 ---------