Trying to build some code (Lua bindings for POSIX APIs) with a gnulib-ized build system, I find that some APIs on GNU systems need extra treatment (i.e. GNU is not POSIX-1.2001 by default). For example, for crypt(3) I need to define _XOPEN_SOURCE, and for some realtime functions such as clock_getres, I need to define XOPEN_REALTIME.
I can't find any gnulib extensions that bear on this: extensions is already running because of something else, and AC_USE_SYSTEM_EXTENSIONS similarly is already active. Similarly, I can't find anything in the autoconf manual. The crypt example is particularly annoying, as without _XOPEN_SOURCE defined it's not defined, even though POSIX_VERSION is >= 200112L, and it's in that version of POSIX (of course, that's a glibc bug, not a problem with gnulib, but it would be nice to fix it in gnulib). Have I missed anything, or is this a gap in gnulib's coverage? In particular, I note that the latest version of standards coverage (including outside POSIX) supported by glibc requires _XOPEN_SOURCE to be defined to 700, and nothing in gnulib seems to do that. -- http://rrt.sc3d.org
