[cairo] [PATCH 4/4] configure.ac: Fix broken build for Qt backend

[Bryce W. Harrington]

When --enable-qt is specified, the build will break on newer versions of
gcc with linker errors like:

  CCLD     cairo-test-suite
/usr/bin/ld: ../boilerplate/.libs/libcairoboilerplate.a(libcairoboilerplate_cxx_la-cairo-boilerplate-qt.o): undefined reference to symbol '__gxx_personality_v0@@CXXABI_1.3'
//usr/lib/x86_64-linux-gnu/libstdc++.so.6: error adding symbols: DSO missing from command line
collect2: error: ld returned 1 exit status

This is because we're not linking against libstdc++ and libQtGui as
required.

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=59038
Signed-off-by: Bryce Harrington <b.harrington at samsung.com>
---
 configure.ac |    1 +
 1 file changed, 1 insertion(+)

diff --git a/configure.ac b/configure.ac
index fca6fc5..6af5144 100644
--- a/configure.ac
+++ b/configure.ac
@@ -191,6 +191,7 @@ CAIRO_ENABLE_SURFACE_BACKEND(qt, Qt, no, [
 		    [qt_REQUIRES=""
 		     use_qt="no (requires Qt4 development libraries)"
 		     ])
+  qt_NONPKGCONFIG_LIBS="-lQtGui -lstdc++"
 ])
 
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1.7.9.5