Permission denied @ dir_s_mkdir - /Users/XXXX/.gem/ruby/2.6.0/extensions/universal-darwin-22/2.6.0/ffi-1.16.3

概要

gem install --user-install ffi -- --enable-libffi-alloc

ターミナルで上記のコマンドを実行したら

Ignoring ffi-1.15.5 because its extensions are not built. Try: gem pristine ffi --version 1.15.5
Ignoring json-1.8.6 because its extensions are not built. Try: gem pristine json --version 1.8.6
Fetching ffi-1.16.3.gem
WARNING:  You don't have /Users/baba-s/.gem/ruby/2.6.0/bin in your PATH,
      gem executables will not run.
Building native extensions with: '--enable-libffi-alloc'
This could take a while...
ERROR:  While executing gem ... (Errno::EACCES)
    Permission denied @ dir_s_mkdir - /Users/baba-s/.gem/ruby/2.6.0/extensions/universal-darwin-22/2.6.0/ffi-1.16.3

上記のエラーが出た

sudo gem install --user-install ffi -- --enable-libffi-alloc

sudo を付けてコマンドを実行したら

Password:
Ignoring ffi-1.15.5 because its extensions are not built. Try: gem pristine ffi --version 1.15.5
Ignoring json-1.8.6 because its extensions are not built. Try: gem pristine json --version 1.8.6
Fetching ffi-1.16.3.gem
WARNING:  You don't have /Users/baba-s/.gem/ruby/2.6.0/bin in your PATH,
      gem executables will not run.
Building native extensions with: '--enable-libffi-alloc'
This could take a while...
ERROR:  Error installing ffi:
    ERROR: Failed to build gem native extension.

    current directory: /Users/baba-s/.gem/ruby/2.6.0/gems/ffi-1.16.3/ext/ffi_c
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/ruby -I /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0 -r ./siteconf20240412-63830-11oy4rr.rb extconf.rb --enable-libffi-alloc
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers.  Check the mkmf.log file for more details.  You may
need configuration options.

Provided configuration options:
    --with-opt-dir
    --without-opt-dir
    --with-opt-include
    --without-opt-include=${opt-dir}/include
    --with-opt-lib
    --without-opt-lib=${opt-dir}/lib
    --with-make-prog
    --without-make-prog
    --srcdir=.
    --curdir
    --ruby=/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/bin/$(RUBY_BASE_NAME)
    --with-ffi_c-dir
    --without-ffi_c-dir
    --with-ffi_c-include
    --without-ffi_c-include=${ffi_c-dir}/include
    --with-ffi_c-lib
    --without-ffi_c-lib=${ffi_c-dir}/lib
    --enable-debug
    --disable-debug
    --enable-system-libffi
    --disable-system-libffi
    --with-libffi-config
    --without-libffi-config
    --with-pkg-config
    --without-pkg-config
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:467:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:546:in `block in try_link0'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/tmpdir.rb:93:in `mktmpdir'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:543:in `try_link0'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:570:in `try_link'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:672:in `try_ldflags'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:1832:in `pkg_config'
    from extconf.rb:9:in `system_libffi_usable?'
    from extconf.rb:46:in `<main>'

To see why this extension failed to compile, please check the mkmf.log which can be found here:

  /Users/baba-s/.gem/ruby/2.6.0/extensions/universal-darwin-22/2.6.0/ffi-1.16.3/mkmf.log

extconf failed, exit code 1

Gem files will remain installed in /Users/baba-s/.gem/ruby/2.6.0/gems/ffi-1.16.3 for inspection.
Results logged to /Users/baba-s/.gem/ruby/2.6.0/extensions/universal-darwin-22/2.6.0/ffi-1.16.3/gem_make.out

エラーの内容が変化した

xcode-select --install

上記のコマンドを実行して Xcode のコマンドラインツールをインストールして

sudo gem install --user-install ffi -- --enable-libffi-alloc

もう一度上記のコマンドを実行してみてもエラーが変わらなかった

xcode-select -print-path

上記のコマンドで使用しているコマンドラインツールを確認したら

/Applications/Xcode15.2.app/Contents/Developer

Xcode 内臓のコマンドラインツールが設定されていたので

sudo xcode-select -switch /Library/Developer/CommandLineTools

上記のコマンドを実行して、xcode-select --install でインストールした
コマンドラインツールを使うようにして

sudo gem install --user-install ffi -- --enable-libffi-alloc

もう一度上記のコマンドを実行してみたら

Ignoring ffi-1.15.5 because its extensions are not built. Try: gem pristine ffi --version 1.15.5
Ignoring json-1.8.6 because its extensions are not built. Try: gem pristine json --version 1.8.6
WARNING:  You don't have /Users/baba-s/.gem/ruby/2.6.0/bin in your PATH,
      gem executables will not run.
Building native extensions with: '--enable-libffi-alloc'
This could take a while...
Successfully installed ffi-1.16.3
Parsing documentation for ffi-1.16.3
Installing ri documentation for ffi-1.16.3
Done installing documentation for ffi after 13 seconds
1 gem installed

成功した

インストールした Xcode のコマンドラインツールが不要になったので

sudo xcode-select -switch /Applications/Xcode15.2.app/Contents/Developer

上記のコマンドで Xcode 内臓のコマンドラインツールを使うように変更して

sudo rm -rf /Library/Developer/CommandLineTools

インストールしたコマンドラインツールを削除した

参考サイト様

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