Deploy DLL for ARM64 and AMD64 in the same PATH?

[Brian Inglis]

On 2025-09-03 13:56, Jeremy Drake via Cygwin wrote:
> On Wed, 3 Sep 2025, Mark Liam Brown via Cygwin wrote:
> 
>> Greetings
>>
>> Our software needs a 3rd party DLL (we cannot change the name...), but
>> we want to support ARM64 together with AMD64.
>>
>> Does Windows or Cygwin have a mechanism to deal with the situation
>> that both expects the DLL to be in the same path?
> 
> Not really.  The closest thing is ARM64EC and ARM64X, a DLL built with
> those will let you use the same DLL for both ARM64 and x64, but only on
> ARM64.  I know there has been work to support those in LLVM/LLD and
> mingw-w64, don't know about gcc/binutils support.
> 
> I think they expect the installer to decide which type of DLL to install
> based on the host machine...

Cygwin x86_64 and aarch64 have to be installed under different Cygwin root 
directories, and the binaries and libraries under each root's /bin/, so no 
conflict can occur.

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

La perfection est atteinte                   Perfection is achieved
non pas lorsqu'il n'y a plus rien à ajouter  not when there is no more to add
mais lorsqu'il n'y a plus rien à retrancher  but when there is no more to cut
                                 -- Antoine de Saint-Exupéry