Hi Takashi,
On 7/6/2026 5:45 PM, Takashi Yano wrote:
Hi Mark,
On Mon, 6 Jul 2026 16:47:43 -0700
Mark Geisert wrote:
Currently madvise() and posix_madvise() are wired together as one
function: the latter. But their error returns should be different.
Make madvise a first-class export in cygwin.din; code a new madvise()
that calls posix_madvise() and massages any error return.
Reported-by: Christian Franke <[email protected]>
Addresses: https://cygwin.com/pipermail/cygwin/2026-July/259872.html
Signed-off-by: Mark Geisert <[email protected]>
Fixes: 61522196c715 (* Merge in cygwin-64bit-branch.)
---
winsup/cygwin/cygwin.din | 2 +-
winsup/cygwin/include/cygwin/version.h | 3 ++-
winsup/cygwin/mm/mmap.cc | 12 ++++++++++++
3 files changed, 15 insertions(+), 2 deletions(-)
diff --git a/winsup/cygwin/cygwin.din b/winsup/cygwin/cygwin.din
index 2e53bc819..937eacdaf 100644
--- a/winsup/cygwin/cygwin.din
+++ b/winsup/cygwin/cygwin.din
@@ -951,7 +951,7 @@ lseek SIGFE
lsetxattr SIGFE
lstat SIGFE
lutimes SIGFE
-madvise = posix_madvise SIGFE
+madvise SIGFE
makecontext NOSIGFE
mallinfo SIGFE
malloc SIGFE
diff --git a/winsup/cygwin/include/cygwin/version.h
b/winsup/cygwin/include/cygwin/version.h
index 71ac5282b..fc838e23e 100644
--- a/winsup/cygwin/include/cygwin/version.h
+++ b/winsup/cygwin/include/cygwin/version.h
@@ -502,12 +502,13 @@ details. */
360: Add RLIMIT_NPROC.
361: Export _Fork.
362: Export C23 stdbit functions.
+ 363: Export madvise separately from posix_madvise.
Note that we forgot to bump the api for ualarm, strtoll, strtoull,
sigaltstack, sethostname. */
#define CYGWIN_VERSION_API_MAJOR 0
-#define CYGWIN_VERSION_API_MINOR 362
+#define CYGWIN_VERSION_API_MINOR 363
/* There is also a compatibity version number associated with the shared memory
regions. It is incremented when incompatible changes are made to the
shared
I don't think we should change CYGWIN_VERSION_API_MINOR value
because the API itself is not changed. This patch fixes a bug
in madvice() implementation.
I went back and forth internally on whether the minor version should be
bumped. One point was whether divorcing madvise() from posix_madvise()
in cygwin.din warranted an API bump: without a bump won't existing
programs be unable to access the new error return behavior? Another
point was that the error return behavior of madvise() is being changed;
isn't that behavior part of the API? I agree this is a bug fix but such
fixes could cause API changes.
This is a case where I'd like to get input from other folks who might've
made similar changes to Cygwin over its long history. I am totally OK
with removing the API bump in a v2 patch if that's the consensus opinion.
Thank you for the review!
..mark
