[Freeciv-Dev] autoconf destroys use of $datadir

[Jason Dorje Short <jdorje@xxxxxxxxx>]

In new versions of autoconf (as present in debian unstable for months now)

  $datadir is set to "${datarootdir}" (not expanded)
  $datarootdir is set to "${prefix}" (not expanded)
  $prefix is set to "NONE"

This is, simply, absurdly obnoxious.  In the first place you can never 
actually use $datadir.  You have to use an auto-expander like 
FC_EXPAND_DIR or AC_GGZ_UNQUOTEDPATH.  Further, FC_EXPAND_DIR only 
expands once and thus needs to be fixed.  Finally, since no prefix is 
set by default you have to set one manually before you can use this.
And not only that, but this affects all previous versions of freeciv as 
well.  I cannot even compile Freeciv 2.0 anymore because of this misfeature.
Supposedly the way these are intended to be used is in cflags, rather 
than in config.h.  The attached patch changes this, and seems to work 
(for 2.1).
-jason

Index: configure.ac
===================================================================
--- configure.ac        (revision 12296)
+++ configure.ac        (working copy)
@@ -597,10 +597,11 @@
 FC_EXPAND_DIR(FREECIV_DATADIR, "$datadir/freeciv")
 
 if test x"$MINGW32" = xyes; then
-  AC_DEFINE_UNQUOTED(DEFAULT_DATA_PATH, ".;data;~/.freeciv;$FREECIV_DATADIR", 
[Mingw32-specific path])
+  DEFAULT_DATA_PATH=".;data;~/.freeciv;$datadir/freeciv"
 else
-  AC_DEFINE_UNQUOTED(DEFAULT_DATA_PATH, ".:data:~/.freeciv:$FREECIV_DATADIR", 
[Freeciv data path])
+  DEFAULT_DATA_PATH=".:data:~/.freeciv:$datadir/freeciv"
 fi
+CPPFLAGS="$CPPFLAGS -DDEFAULT_DATA_PATH=\\\"$DEFAULT_DATA_PATH\\\""
 
 dnl This has to be last library
 if test -n "$WITH_EFENCE"; then