Re: ANN: GNUstep Windows MSVC Toolchain Scripts

[David Chisnall]

On 20 Mar 2021, at 10:49, Frederik Seiffert <frederik@algoriddim.com> wrote:
>> If you look at the build for libobjc2 on Windows, because we're using a 
>> CMake version that predates official support for either Objective-C or using 
>> the gcc-compatible driver, we have the same problem with /TP being added.  
>> We work around this with an undocumented feature of clang where you can 
>> provide an environment variable that removes flags from the command line.  
>> You can probably set that in your Visual Studio build. Setting this strips 
>> the TC and TP flags from clang invocations:
>> 
>> CCC_OVERRIDE_OPTIONS=x-TC x-TP x/TC x/TP
> 
> Good idea using CCC_OVERRIDE_OPTIONS, that should probably work fine. 
> Ultimately I’m hoping that we can come up with something more integrated like 
> a custom build tool spec in VS, so .m and .mm files automatically get all the 
> right flags.

It’s definitely not the *right* solution, but it should work for now.  VS Code 
now has really good CMake support and I think it’s reasonable in VS as well.  
I’d love to see GNUstep adopt CMake - with the last release, it officially 
supports Objective-C and using clang with the gcc-like driver on Windows, so it 
would give us the ability to generate XCode projects, Visual Studio projects, 
and something that VS Code supports natively.

>> It would be great at some point to remove the pthread-w32 dependency. 
>> SRWLocks and ConditionVariables on Windows seem to provide everything we 
>> need for NSLock* and be a fairly small amount of code.
> 
> Yeah absolutely, I just wanted to make sure we could actually get this 
> working before spending time on improvements. I also expect to spend a lot of 
> time on fixes while integrating the toolchain in our project.

The SRWLock APIs were introduced with Windows 7, as I recall.  Last time I 
looked at this, there were enough XP machines that folks cared about that it 
didn’t make sense to use them, but now Windows 7 is effectively out of support 
so is a reasonable baseline.

David