These variables are supposed to be set by user. What we can do in
configure is to set another variable and AC_SUBST() it. Then in
Makefile.am we assign it to AM_{CFLAGS,LDFLAGS}. This way user can
always override their values, in configure or make phase.
Reference: http://www.gnu.org/software/automake/manual/html_node/Flag-Variables-Ordering.html
This is mostly just preparation for the next patch. But this macro is
used for flags that are only needed during linking but that don't
make sense for normal compilation.
I saw this exact type of patch online for systemd, but it never seems to
have actually been incorporated into their attributes.m4.
Current limitation is horrible no support to sections: we have to to
have separate header files or to maintain the libkmod-sections.txt file.
We are doing the latter.
