The check for the libaubio version does not work on Debian testing,
where libaubio is available in version 0.4.0 only. Here is the relevant
extract from config.log:
configure:20141: checking for LIBAUBIO_4
configure:20148: $PKG_CONFIG --exists --print-errors "aubio >= 4"
Requested 'aubio >= 4' but
Trying to compile on Debian stable with -Wformat -Werror=format-security
(the Debian build script uses that), I get the following error in
tools/cairo_svg2path.c:
gcc -DHAVE_CONFIG_H -I. -I.. -D_FORTIFY_SOURCE=2 -g -O2
-fstack-protector --param=ssp-buffer-size=4 -Wformat
-Werror=format-security
