cmake requires curl

[ryandesign (Ryan Carsten Schmidt)]

Why does cmake require curl? This means that curl can't depend on anything that requires cmake, such as brotli. See #65065.

[ryandesign (Ryan Carsten Schmidt)]

If it is important that cmake continue to use curl, then another solution is for brotli to stop using cmake (#65069).

[michaelld (Michael Dickens)]

Looking into this, as it's a -very- good question. I'm guessing I can move the curl dependency to test from depends (or just remove it since we don't have tests setup in the Portfile)

[ryandesign (Ryan Carsten Schmidt)]

cmake binaries link with curl:

$ otool -L /opt/local/bin/{ccmake,cmake,cpack,ctest}|egrep '^/|curl'
/opt/local/bin/ccmake:
	/opt/local/lib/libcurl.4.dylib (compatibility version 12.0.0, current version 12.0.0)
/opt/local/bin/cmake:
	/opt/local/lib/libcurl.4.dylib (compatibility version 12.0.0, current version 12.0.0)
/opt/local/bin/cpack:
	/opt/local/lib/libcurl.4.dylib (compatibility version 12.0.0, current version 12.0.0)
/opt/local/bin/ctest:
	/opt/local/lib/libcurl.4.dylib (compatibility version 12.0.0, current version 12.0.0)

So you can't just remove the dependency from depends_lib. You would also have to tell the build system not to link with MacPorts curl even if it is installed. But I don't know if that's the right thing to do.

cmake was made to use MacPorts curl to resolve #43133, in which cmake was trying to fetch a file but couldn't, because previously cmake was using a bundled copy of curl which didn't support https. Certainly I agree with the general preference for using MacPorts libraries over potentially out-of-date bundled libraries.

I don't know how important it is for cmake itself to be able to ​fetch content. In MacPorts ports of course we would prefer that that not happen, but users may also use MacPorts cmake for their own non-MacPorts projects, and they might expect this functionality to exist.

Therefore it's probably best for cmake to continue to link with MacPorts curl and for a different resolution to the circular dependency to be found.

[michaelld (Michael Dickens)]

Thanks for the background; I'd forgotten about some parts there.

My search indeed shows that we use an externally provided curl & that is part of the core cmake codebase. Based on the reasoning you note, I agree with you that it's wiser for us to continue using the externally provided curl & fix the circular dependency in some other way.

[kencu (Ken)]

cmake-bootstrap is new enough to build brotli and has no deps, so that might be a simple fix