Problems (and a workaround) with zlib and Windows Dev Channel

Brian Inglis
Sat Oct 31 21:16:39 GMT 2020

On 2020-10-31 14:19, Teemu via Cygwin wrote:
> I noticed that some programs that depend on zlib stopped working and started creating stackdumps with Windows Dev Channel build 20246.1. I could not get gdb working with zlib but I figured a workaround: I recompiled zlib with cygport using the latest gcc (10.2.0) and copied the dll over the old one. That did fix the problem.
> Regards,Teemu

Hi Teemu,

Could this have been a BLODA caused by your AV package e.g. Windows Defender?
Some utilities e.g. Tortoise <VCS> also install DLL intercepts that can break
Cygwin, so you have to drop them from Cygwin PATH.

Do you happen to know the zlib version you were running?
You can check under your local package directory:

$ ls -t $PACKAGE/x86*/release/zlib/zlib0/
zlib0-1.2.11-1.tar.xz  zlib0-1.2.8-3.tar.xz  zlib0-1.2.8-1.tar.bz2
zlib0-1.2.7-1.tar.bz2  zlib0-1.2.5-1.tar.bz2

Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

This email may be disturbing to some readers as it contains
too much technical detail. Reader discretion is advised.
[Data in binary units and prefixes, physical quantities in SI.]

More information about the Cygwin mailing list