[tom_]

What does it require over and above what you'd need for development anyway? The vagrant provision script for my Ubuntu VM installs this lot before grabbing the CMake source and building it:

    apt-get -y install subversion git make gcc g++ subversion emacs git-gui zip gksu synaptic gdb valgrind

I'm pretty sure that not all of these are actually required. You do need gcc and g++, I'm sure, but I expect Valgrind and GDB are strictly optional...

[nwmcsween]

Gentoo lists:

    app-crypt/rhash
    >=app-arch/libarchive-3.0.0:=
    >=dev-libs/expat-2.0.1
    >=dev-libs/libuv-1.10.0:=
    >=net-misc/curl-7.21.5[ssl]
    sys-libs/zlib
    virtual/pkgconfig
    emacs? ( virtual/emacs )
    system-jsoncpp? ( >=dev-libs/jsoncpp-0.6.0_rc2:0= )

of which most have dependencies as well which is honestly ridiculous for a build system.

[pedrocr]

Those look like exactly the kinds of dependencies I'd go for if I needed to write a new C build system. Nothing ridiculous about them.

[quietbritishjim]

The emacs dependency is odd to say the least, but I'm pretty sure CMake doesn't actually depend on it. I don't know much about Gentoo but perhaps the question mark after it means it's just a suggested dependency.

[rleigh]

It will be the cmake-mode for editing CMakeLists.txt files.

[nwmcsween]

Anything dep a ? is optional

[tom_]

Perhaps they configured it that way? Maybe these are optional dependencies that provide additional functionality.

I was able to build it on a Ubuntu VM after installing no more than gcc, g++ and make.

apt list --installed suggests this VM does have a surprising amount of stuff installed (more than I'd expected at any rate), but of the dependencies you list it appears to have zlib, curl, and nothing else.

[nwmcsween]

Gentoo gives 'use' flags for configurable options, I stripped those out and posted the hard dependencies.

[__flo]

FreeBSD only lists 6:

> libcurl.so : ftp/curl > libexpat.so : textproc/expat2 > libjsoncpp.so : devel/jsoncpp > libuv.so : devel/libuv > librhash.so : security/rhash > libarchive.so.13 : archivers/libarchive

https://www.freshports.org/devel/cmake/

I also build CMake from source on Ubuntu (because they used to ship ridicously ancient versions and I have keep doing it since) and there is the possibility to use bundled versions of those dependencies. Also, for a development tool I see nothing wrong with those dependencies, I do not have to redistribute all of this.

And for those compiling everything from source like Gentoo or FreeBSD ports users, I do not understand it because most of the time is spent on building gcc or clang anyway which is absolutely not optional.