编译器未能生成可执行文件。 (RuntimeError) 在 macOS 中安装 unf_ext 时

Question

when I am using this command in macOS 10.15.7 to install unf_ext :

sudo gem install unf_ext -v '0.0.7.7' --source 'https://gems.ruby-china.com'

shows this error:

/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/universal-darwin19/rbconfig.rb:229: warning: Insecure world writable dir /Users/dolphin in PATH, mode 040777
Building native extensions. This could take a while...
ERROR:  Error installing unf_ext:
    ERROR: Failed to build gem native extension.

    current directory: /Library/Ruby/Gems/2.6.0/gems/unf_ext-0.0.7.7/ext/unf_ext
/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 ./siteconf20210121-81858-8bev42.rb extconf.rb
/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/universal-darwin19/rbconfig.rb:229: warning: Insecure world writable dir /Users/dolphin in PATH, mode 040777
checking for -lstdc++... *** 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-static-libstdc++
    --without-static-libstdc++
    --with-stdc++lib
    --without-stdc++lib
/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:789:in `try_func'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:1016:in `block in have_library'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:959:in `block in checking_for'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:361:in `block (2 levels) in postpone'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:331:in `open'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:361:in `block in postpone'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:331:in `open'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:357:in `postpone'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:958:in `checking_for'
    from /System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/lib/ruby/2.6.0/mkmf.rb:1011:in `have_library'
    from extconf.rb:6:in `<main>'

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

  /Library/Ruby/Gems/2.6.0/extensions/universal-darwin-19/2.6.0/unf_ext-0.0.7.7/mkmf.log

extconf failed, exit code 1

Gem files will remain installed in /Library/Ruby/Gems/2.6.0/gems/unf_ext-0.0.7.7 for inspection.
Results logged to /Library/Ruby/Gems/2.6.0/extensions/universal-darwin-19/2.6.0/unf_ext-0.0.7.7/gem_make.out

I have aready tried:

$ xcode-select --install

xcode-select: error: command line tools are already installed, use "Software Update" to install updates

still not work, what should I do to fix it?

Answer 1

cat /Library/Ruby/Gems/2.6.0/extensions/universal-darwin-19/2.6.0/unf_ext-0.0.7.7/gem_make.out can get the detail reason.

To me the dumped cause is: /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks/Ruby.framework/Versions/2.6/usr/include/ruby-2.6.0/ruby/ruby.h:24:10: note: did not find header 'config.h' in framework 'ruby' (loaded from '/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/System/Library/Frameworks') 1 error generated.

It seems an incompatible issue with Xcode and macOS versions. macOS 10.15 and Xcode 12 don't work well together. You can check https://github.com/CocoaPods/CocoaPods/issues/10286

Answer 2

Just clarifying Robin Chen's answer, which I upvoted for providing the link to the CocoaPods ticket .

This does seem to be an issue with Xcode/macOS versions mismatch (I have Monterey 12.6.3 with Xcode 14.2).

Following the method provided in this comment fixed the issue in my case (all credit to comment's author); namely:

macos_major_vers=$(sw_vers -productVersion | sed 's/^\([^.]*\)\..*$/\1/')
echo $macos_major_vers      # should show smth like '12'
export SDKROOT=/Library/Developer/CommandLineTools/SDKs/MacOSX${macos_major_vers}.sdk
sudo gem install ...