xml-introspection.S causes rtkit-daemon to have an executable stack

[mkszuba]

This has already been both reported and explained in the Arch Linux bug tracker (https://bugs.archlinux.org/task/65699) so let me just mention here, for completeness, that setting the stack markings by adding

#if defined(__linux__) && defined(__ELF__)
.section .note.GNU-stack,"",%progbits
#endif

at the beginining of xml-introspection.S makes the problem go away without, as far as I can tell from using a thus modified version of rtkit under Gentoo, any drawbacks.

This solution comes straight from generic Gentoo instructions for dealing with the executable stack and I take no credit for it, which is why I am posting it in an issue rather than submitting a pull request.

[heftig]

The current master replaces the use of assembler with xxd to convert the file into C code. The resulting file will be distributed in the tarballs, so xxd is not necessary.

[mkszuba]

Gah, I really should look at the master branch and not just at 0.12 before doing anything here. This is why I initially omitted meson while making libsystemd optional, too... Anyway, that's handy - and come next release, no more patches in Gentoo ebuilds of rtkit!