If $PKG_CONFIG contains a space, then the test may not work, so
surround with quotation mark characters. (for example,
PKG_CONFIG="pkg-config --static" breaks configure before this commit).
In m4/curses.m4, line 134, the 5th argument passed to AC_NCURSES was
surrounded by '"' instead of '[' and ']'. Because of that, the expansion
of AC_NCURSES in that case would produce the following line inside the
configure script (note the repeated double quotes):
screen_manager=""ncurses on $withval/include""
That would cause the following error when configure was executed with
the "--with-ncurses=dir" argument:
./configure: line 13468: on: command not found
Although in the case above the error doesn't actually influence the
build process ('screen_manager' isn't used anywhere in the script),
trying to execute 'on' might be harmful if it corresponded to an
existing command in the user's environment.
Silences notice on newer autoconf:
libtoolize: Consider adding `AC_CONFIG_MACRO_DIR([m4])' to configure.ac and
libtoolize: rerunning libtoolize, to keep the correct libtool macros in-tree.
This helps keep the top-level build directory clean, too
