More specifically, it takes 1m45 on my armv7 build machine; the default timeout
is 30s.

diff -x config.log -x config.status -ru tmp/pango-1.40.10/tests/meson.build work/pango-1.40.10/tests/meson.build
--- tmp/pango-1.40.10/tests/meson.build	2017-08-16 00:51:10.000000000 +0100
+++ work/pango-1.40.10/tests/meson.build	2017-08-16 16:36:22.297682825 +0100
@@ -125,5 +125,7 @@
                    install: true,
                    install_dir: installed_test_bindir)
 
-  test(name, bin, env: test_env)
+  # test-pangocairo-threads can take a couple of minutes to run on a slow
+  # machine.
+  test(name, bin, env: test_env, timeout: 4 * 60)
 endforeach
