[cairo] [PATCH v2 0/3] Build fixes

[Bryce W. Harrington]

I'd appreciate a second set of eyes on these patches.  
I've verified config and build with them on ubuntu 12.04 and 14.04.

The first eliminates a series of warnings about the archiver when
running autogen.sh with automake 1.12.

The second one adds a workaround for build issues when using older gccs.
A lot of distros are carrying this patch or something equivalent.

The last one fixes the Qt backend by linking against the required stdc++
library.  Usually this is automatic since g++ is used to link, but we're
not so need to link the lib explicitly.

Update v2:
  * Dropped the subdir-objects patch, as it changes where build output
    files are placed.
  * Dropped manual specification of -lQtGui for the Qt backend; further
    testing shows this does indeed get picked up automatically via
    pkg-config.
  * Improved commit messages 

Bryce Harrington (3):
  configure.ac: Quell warnings about AM_PROG_AR when using automake 1.12
  configure.ac: Add a --disable-lto configure option
  configure.ac: Fix broken build for Qt backend

 build/configure.ac.warnings | 15 ++++++++++-----
 configure.ac                |  2 ++
 2 files changed, 12 insertions(+), 5 deletions(-)

-- 
1.9.1