expat.h is (in most Linux distributions, at least) located directly in
/usr/include. Because the compiler is called with the src directory in
the include path, the include of <expat/expat.h> happens to work but
results in the bundled version of the header being used instead of the
system version.
Fedora (and, I supposed, most recent Linux distros) build everything
with -Werror=format-security. If you attempt to build with
-DSLIC3R_PERL_XS (which we need in order to run the test suite), the
build fails because of two strings in the Perl XS code:
/usr/bin/perl -MExtUtils::XSpp::Cmd -e xspp -- -t "/builddir/build/BUILD/PrusaSlicer-version_2.0.0-rc2/xs/xsp/typemap.xspt" "/builddir/build/BUILD/PrusaSlicer-version_2.0.0-rc2/xs/xsp/Print.xsp":585:31: error: format not a string literal and no format arguments [-Werror=format-security]
Ths fixes up two instances of that.
Jason Tibbitts