From Fedora Project Wiki

  • Add the following sentences at the end of Ruby packages with binary content/shared libraries

For packages which create C shared libraries using extconf.rb

export CONFIGURE_ARGS="--with-cflags='%{optflags}'"

should be used to pass CFLAGS to Makefile correctly. This also applies to Ruby Gems.

  • Add the below section:

Ruby Gem with extension libraries written in C

When Ruby Gem contains extension libraries written in C,

  • First, %prep stage must contain %setup -q -c -T to create the directory where C libraries are compiled.
  • Then at %build stage the Ruby Gem must be installed under the directory created at %prep stage to get C libraries compiled under there.
  • When gem install is used to install Gem file, using -V option is recommend to check if CFLAGS is correctly honored.
  • Finally at %install stage the whole tree under the directory created at %prep stage should be copied (not moved) to under %{buildroot}%{gemdir}.
    • When all tree under the directory created at %prep stage is moved to under %{buildroot}, find_debuginfo.sh will complain that the corresponding source files are missing.
  • Installed C codes (usually under %{geminstdir}/etc) may be removed even if gem contents %{gemname} reports that installed C codes should be found there.

If the Gem contains binary content (e.g., for a database driver), it must be marked as architecture specific, and all architecture specific content must be moved from the %{gemdir} to the [#ruby_sitearch %{ruby_sitearch} directory] during %install

Example

%prep
%setup -q -T -c

%build
mkdir -p ./%{gemdir}
export CONFIGURE_ARGS="--with-cflags='%{optflags}'"
gem install --local --install-dir ./%{gemdir} -V --force %{SOURCE0}

%install
rm -rf %{buildroot}
mkdir -p %{buildroot}%{gemdir}
cp -a ./%{gemdir}/* %{buildroot}%{gemdir}

mkdir -p %{buildroot}%{ruby_sitearch}
mv %{buildroot}%{geminstdir}/lib/*.so %{buildroot}%{ruby_sitearch}
rm -rf %{buildroot}%{geminstdir}/ext

%clean
rm -rf %{buildroot}

%files
%defattr(-,root,root,-)
%{ruby_sitearch}/*.so
%{geminstdir}/
%{gemdir}/cache/%{gemname}-%{version}.gem
%{gemdir}/specifications/%{gemname}-%{version}.gemspec