Mac mini（Catalina）に Jubatus をインストール。「brew install」の方でエラー（続き）とりあえず、brew install llvm

https://apple.stackexchange.com/questions/227026/how-to-install-recent-clang-with-homebrew
に、
Now it's enough to run:
　brew install llvm
The bottle now includes clang by default.
と書かれていたので、とりあえずやってみる。

https://ja.stackoverflow.com/questions/35294/homebrewでclangをinstallしようとするとerror
には、
https://formulae.brew.sh/formula/ にある Homebrew の formula 一覧を見ると分かりますが、現在 clang という formula は無いので「見つからないよ」というエラーが出ています。
2018 年 7 月現在、代わりに llvm という formula が提供されています。Xcode の Apple Clang とどう共存させるかに応じて、brew install llvm または brew install --with-toolchain llvm でインストールすることができます。
と書かれている。

https://formulae.brew.sh/formula/llvm
（の下の方）を見ると、「--with-toolchain llvm」を付けて実行している人はかなり少数のようなので（って、そういうふうに見るんだと推測）、よしとする。
→というか、このオプション付けたら、これもまた brew install からそんなオプション無いよと怒られた。


でも、これをやったからといって、「--use-clang」を使えるとか、もしくはそれ相当ができるのかはよくわからない。
(^_^;

＊＊＊

$ brew install llvm
Updating Homebrew...
==> Auto-updated Homebrew!
Updated 1 tap (homebrew/core).
==> Updated Formulae
gdal gmic gmt gmt@5 libtorch nco ncview netcdf pcl pdal qmmp vtk

==> Installing dependencies for llvm: libffi, pcre and swig
==> Installing llvm dependency: libffi
==> Downloading https://homebrew.bintray.com/bottles/libffi-3.2.1.catalina.bottle.tar.gz
######################################################################## 100.0%
==> Pouring libffi-3.2.1.catalina.bottle.tar.gz
==> Caveats
libffi is keg-only, which means it was not symlinked into /usr/local,
because some formulae require a newer version of libffi.

For compilers to find libffi you may need to set:
export LDFLAGS="-L/usr/local/opt/libffi/lib"

==> Summary
/usr/local/Cellar/libffi/3.2.1: 16 files, 300.7KB
==> Installing llvm dependency: pcre
==> Downloading https://homebrew.bintray.com/bottles/pcre-8.43.catalina.bottle.tar.gz
==> Downloading from https://akamai.bintray.com/35/3517eab75bf5bdb7798414d0af2aaaaf43edd248abc960b008d89b0a0958d537?__gda__=exp=1579271211~hm
######################################################################## 100.0%
==> Pouring pcre-8.43.catalina.bottle.tar.gz
/usr/local/Cellar/pcre/8.43: 204 files, 5.5MB
==> Installing llvm dependency: swig
==> Downloading https://homebrew.bintray.com/bottles/swig-4.0.1.catalina.bottle.tar.gz
==> Downloading from https://akamai.bintray.com/d4/d44eb5e2ae81970d131618c4ddd508d3d798e9465979a125454db75c3b9125e1?__gda__=exp=1579271214~hm
######################################################################## 100.0%
==> Pouring swig-4.0.1.catalina.bottle.tar.gz
/usr/local/Cellar/swig/4.0.1: 723 files, 5.4MB
==> Installing llvm
==> Downloading https://homebrew.bintray.com/bottles/llvm-9.0.0_1.catalina.bottle.tar.gz
==> Downloading from https://akamai.bintray.com/a8/a8e2475a1fc5a81f0da83a73d17fd54cc2a686f7b5d8e7ace9ea18885971415f?__gda__=exp=1579271217~hm
######################################################################## 100.0%
==> Pouring llvm-9.0.0_1.catalina.bottle.tar.gz
==> Caveats
To use the bundled libc++ please add the following LDFLAGS:
LDFLAGS="-L/usr/local/opt/llvm/lib -Wl,-rpath,/usr/local/opt/llvm/lib"

llvm is keg-only, which means it was not symlinked into /usr/local,
because macOS already provides this software and installing another version in
parallel can cause all kinds of trouble.

If you need to have llvm first in your PATH run:
echo 'export PATH="/usr/local/opt/llvm/bin:$PATH"' >> ~/.bash_profile

For compilers to find llvm you may need to set:
export LDFLAGS="-L/usr/local/opt/llvm/lib"
export CPPFLAGS="-I/usr/local/opt/llvm/include"

==> Summary
/usr/local/Cellar/llvm/9.0.0_1: 6,839 files, 3.7GB
==> Caveats
==> libffi
libffi is keg-only, which means it was not symlinked into /usr/local,
because some formulae require a newer version of libffi.

For compilers to find libffi you may need to set:
export LDFLAGS="-L/usr/local/opt/libffi/lib"

==> llvm
To use the bundled libc++ please add the following LDFLAGS:
LDFLAGS="-L/usr/local/opt/llvm/lib -Wl,-rpath,/usr/local/opt/llvm/lib"

llvm is keg-only, which means it was not symlinked into /usr/local,
because macOS already provides this software and installing another version in
parallel can cause all kinds of trouble.

If you need to have llvm first in your PATH run:
echo 'export PATH="/usr/local/opt/llvm/bin:$PATH"' >> ~/.bash_profile

For compilers to find llvm you may need to set:
export LDFLAGS="-L/usr/local/opt/llvm/lib"
export CPPFLAGS="-I/usr/local/opt/llvm/include"

$