Re: [PATCH 1/1] Fix detection of pwritev support for OSX.

On 23.01.2021 08:02, Sergey Shinderuk wrote:
> I checked the script [1], and it really requires the CLT. Here is the
> explanation [2] for this:
>
>     There is actually no such requirement. However, there are
>     formulae that will be forced to build from source if you do not
>     have the CLT. They can still be built from source with Xcode
>     only, but because the pre-built bottles are compiled in an
>     environment that has both Xcode and the CLT installed, there are
>     some cases where the bottles end up having a hard dependency on
>     the CLT. A major example is gcc. So installing the CLT may help
>     you avoid some lengthy source builds.
>
>     We ensure that all Homebrew formulae can be built with Xcode.app
>     alone. Most formulae can be built with just the CLT, and those
>     that require the full Xcode.app have an explicit depends_on
>     :xcode => :build. Some users would prefer to use only the CLT
>     because it's a much smaller download and takes less time to
>     install and upgrade than Xcode.

In the gcc formula [1]:

# The bottles are built on systems with the CLT installed, and do not
work
# out of the box on Xcode-only systems due to an incorrect sysroot.
pour_bottle? do
reason "The bottle needs the Xcode CLT to be installed."
satisfy { MacOS::CLT.installed? }
end

I guess this is the "xcrun --show-sdk-path" thing we've alredy disccussed :)

[1] https://github.com/Homebrew/homebrew-core/blob/master/Formula/gcc.rb#L36

--
Sergey Shinderuk
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