Does the Cygwin setup program do internal sanity checks on startup?

[Adam Dinwoodie]

On Wed, Aug 24, 2022 at 08:46:10PM +0000, Brian Cowan via Cygwin wrote:
> Why would I ask that question? Because I have a host running a
> hodgepodge of company-mandated security software, and -- only on that
> host -- the Cygwin setup tool crashes...
> 
> Oddities:
> 1. The crash generates 3 dump files when I use procdump, which is odd
> since I "normally" only get 2 identical dumps from procdump.
> 2. A Websense ForcePoint DLP DLL is loaded in the process space,
> apparently through DLL injection.
> 3. There seem to be 3 threads started, only one of which is the setup
> program's "main" function. I had to get that out of a Process Monitor
> log since the dump files are largely content free.
> 4. The crash is unique to the setup program. Nothing else appears to
> fail.
> 
> The crash is an "illegal instruction" dump, which of course doesn't
> make a lot of sense... This could be one of the other security
> packages/policies on this host being "helpful."
> 
> I need ammunition to take to my internal Mordak's so I can update
> Cygwin... Sure I can use WSL, but not for everything.

This sounds like classic "BLODA": applications that interfere with how
Cygwin provides *nix compatibility.  There's more info in the FAQs at
https://cygwin.com/faq/faq.html#faq.using.bloda, but in short it seems
very likely that this problem is caused by some security software
running on this system.