Gcc error during ruby-xapian-full compilation.

Question

Attempting to install ruby-xapian-full from the AUR results in
checking whether the C compiler works... no
configure: error: in `/tmp/yaourt-tmp-pants/aur-ruby-xapian-full/pkg/usr/lib/ruby/gems/1.9.1/gems/xapian-full-1.2.3/xapian-core-1.2.3':
configure: error: C compiler cannot create executables
See `config.log' for more details.
rake aborted!
The entire config.log is here, but the relevant portion is
configure:3835: gcc -V >&5
gcc: error: unrecognized option '-V'
gcc: fatal error: no input files
compilation terminated.
configure:3846: $? = 1
configure:3835: gcc -qversion >&5
gcc: error: unrecognized option '-qversion'
gcc: fatal error: no input files
compilation terminated.
configure:3846: $? = 1
configure:3866: checking whether the C compiler works
configure:3888: gcc -march=x86-64 -mtune=generic -O2 -pipe -R/tmp/yaourt-tmp-root/aur-ruby-xapian-full/pkg/usr/lib/ruby/gems/1.9.1/gems/xapian-full-1.2.3/lib conftest.c >&5
gcc: error: unrecognized option '-R'
configure:3892: $? = 1
configure:3930: result: no
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME "xapian-core"
| #define PACKAGE_TARNAME "xapian-core"
| #define PACKAGE_VERSION "1.2.3"
| #define PACKAGE_STRING "xapian-core 1.2.3"
| #define PACKAGE_BUGREPORT "http://xapian.org/bugs"
| #define PACKAGE_URL ""
| #define PACKAGE "xapian-core"
| #define VERSION "1.2.3"
| /* end confdefs.h. */
|
| int
| main ()
| {
|
| ;
| return 0;
| }
configure:3935: error: in `/tmp/yaourt-tmp-root/aur-ruby-xapian-full/pkg/usr/lib/ruby/gems/1.9.1/gems/xapian-full-1.2.3/xapian-core-1.2.3':
configure:3939: error: C compiler cannot create executables
See `config.log' for more details.
My makepkg.conf is vanilla.  Looking though the forums, I can see that a usual fix is to merge makepkg.cong and makepkg.conf.pacnew, but I lack a .pacnew for makepkg.  Just in case, my makepkg.conf is here.
Thanks.

Answer 1

So I created a patch for the Rakefile (shown below).
To generate the package as I did:
cd
mkdir aur
cd aur
wget https://aur.archlinux.org/packages/ruby-xapian-full/ruby-xapian-full.tar.gz
tar -xzf ruby-xapian-full.tar.gz
makepkg -o
cd src
gem unpack xapian-full-1.2.3.gem
cd xapian-full-1.2.3
wget 'http://pastebin.com/download.php?i=9n23crey' --output-document Rakefile.patch
patch < Rakefile.patch
gem build xapian-full.gemspec
mv xapian-full-1.2.3.gem ..
cd ../..
makepkg -e
(wait a while)
sudo pacman -U ruby-xapian-full-1.2.3-1-x86_64.pkg.tar.xz