bignum.c: suppress warning

* bignum.c (absint_numwords_generic): suppress false warning in
  rb_absint_numwords() by gcc 4.4.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43722 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
rubygems/source/git.rb: discard output

* lib/rubygems/source/git.rb (Gem::Source::Git#checkout): discard git
  output.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43723 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
rubygems/util.rb: fix Gem::Util.popen

* lib/rubygems/util.rb (Gem::Util.popen): should close open pipe to
  reap the child process, in 1.9 or later.  fix deadlock on waiting
  the child process whose output is bigger than pipe buffer, in 1.8.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@43724 b2dd03c8-39d4-4d8f-98ff-823fe69b080e