Further unify the configure.in scripts.

cadpli/configure.in

@@ -133,81 +133,14 @@ AC_MSG_RESULT($EXTRALIBS)
 ## in order to know the name of the start symbol for the .vpi module.
 #######################
 
-AC_CYGWIN
-AC_EXEEXT
-AC_MINGW32
-
-
-WIN32=no
-AC_MSG_CHECKING("Checking for windows")
-if test "$CYGWIN" = "yes" -o "$MINGW32" = "yes"
-then
-    WIN32=yes
-fi
-AC_SUBST(WIN32)
-AC_MSG_RESULT($WIN32)
-AC_SUBST(EXEEXT)
-
-
-AC_MSG_CHECKING("for leading and/or trailing underscores")
-cat << EOF > underscore.c
-       void underscore(void){}
-EOF
-$CC -shared -c underscore.c > /dev/null 2>&1
-
-CC_LEADING_UNDERSCORE=no
-CC_TRAILING_UNDERSCORE=no
-
-output=`nm underscore.o|grep _underscore 2>&1`
-if test ! -z "$output" -a "$CYGWIN" != "yes" -a "$MINGW32" != "yes"; then
-  CC_LEADING_UNDERSCORE=yes
-  AC_DEFINE(NEED_LU)
-fi
-
-
-
-output=`nm underscore.o|grep underscore_ 2>&1`
-if test ! -z "$output"; then
-  CC_TRAILING_UNDERSCORE=yes
-  AC_DEFINE(NEED_TU)
-fi
-
-if test "$CC_LEADING_UNDERSCORE" = yes; then
-  AC_DEFINE(WLU)
-fi
-if test "$CC_TRAILING_UNDERSCORE" = yes; then
-  AC_DEFINE(WTU)
-fi
-
-rm underscore.c underscore.o
-
-AC_MSG_RESULT("$CC_LEADING_UNDERSCORE $CC_TRAILING_UNDERSCORE")
+AX_C_UNDERSCORES_LEADING
+AX_C_UNDERSCORES_TRAILING
 
 #######################
 ## end of test for underscores
 #######################
 
-
-
-AC_MSG_CHECKING("for ident support in C compiler")
-ident_support='-DHAVE_CVS_IDENT=1'
-case "${host}" in
-
-     *-*-cygwin*)
-	ident_support=
-	;;
-
-     *-*-darwin*)
-	ident_support=
-	;;
-
-     *-*-machten*)
-	ident_support=
-	;;
-esac
-
-AC_SUBST(ident_support)
-AC_MSG_RESULT($ident_support)
+AX_CPP_IDENT
 
 # where to put vpi subdirectories
 AC_MSG_CHECKING(for VPI subdirectories)