upstream: http://bugs.irssi.org/index.php?do=details&task_id=590

#
# Patch managed by http://www.holgerschurig.de/patcher.html
#

--- irssi/configure.in~autofoo
+++ irssi/configure.in
@@ -280,39 +280,24 @@
 AC_CHECK_SIZEOF(long long)
 
 dnl * older autoconfs don't include sys/types.h, so do it manually
-AC_MSG_CHECKING([size of off_t])
-AC_TRY_RUN([
-  #include <stdio.h>
-  #include <sys/types.h>
-  int main() {
-    FILE *f=fopen("conftestval", "w");
-    if (!f) exit(1);
-    fprintf(f, "%d\n", sizeof(off_t));
-    return 0;
-  }
-], [
-  sizeof_off_t=`cat conftestval`
-  rm -f conftestval
-], [
-  AC_ERROR([Unsupported off_t size])
-])
-AC_MSG_RESULT($sizeof_off_t)
+dnl * we use current autotools, so do it properly. --CL
+AC_CHECK_SIZEOF(off_t)
 
-if test $sizeof_off_t = 8; then
+if test $ac_cv_sizeof_off_t = 8; then
   offt_64bit=yes
 else
   offt_64bit=no
 fi
 
-if test x$sizeof_off_t = x$ac_cv_sizeof_long; then
+if test x$ac_cv_sizeof_off_t = x$ac_cv_sizeof_long; then
   # try to use unsigned long always first
   AC_DEFINE_UNQUOTED(PRIuUOFF_T, "lu")
   AC_DEFINE(UOFF_T_LONG)
-elif test x$sizeof_off_t = x$ac_cv_sizeof_int; then
+elif test x$ac_cv_sizeof_off_t = x$ac_cv_sizeof_int; then
   # next try int
   AC_DEFINE_UNQUOTED(PRIuUOFF_T, "u")
   AC_DEFINE(UOFF_T_INT)
-elif test x$sizeof_off_t = x$ac_cv_sizeof_long_long; then
+elif test x$ac_cv_sizeof_off_t = x$ac_cv_sizeof_long_long; then
   # and finally long long
   AC_DEFINE_UNQUOTED(PRIuUOFF_T, "llu")
   AC_DEFINE(UOFF_T_LONG_LONG)
@@ -541,13 +526,13 @@
 int modfunc(){return (int)floor(1.2);}
 EOF
 
-./libtool --mode=compile $CC $CFLAGS -c conftest.c 2> /dev/null > /dev/null
+./*libtool --mode=compile $CC $CFLAGS -c conftest.c 2>log >&2 
 if test ! -s conftest.lo; then
   AC_ERROR([error compiling test module])
 fi
 
 dnl ** link to library
-./libtool --mode=link $CC $CFLAGS $LDFLAGS -rpath /usr/lib conftest.lo -lm -o libconftest.la > /dev/null
+./*libtool --mode=link $CC $CFLAGS $LDFLAGS -rpath /usr/lib conftest.lo -lm -o libconftest.la > /dev/null
 if test ! -s .libs/libconftest.a; then
   AC_ERROR([error, can't even find .a library])
 fi
@@ -755,14 +740,14 @@
 			perl_module_fe_lib=
 			perl_static_lib=libperl_core_static.la
 			perl_static_fe_lib=libfe_perl_static.la
-			PERL_LIBTOOL='$(SHELL) $(top_builddir)/libtool'
+			PERL_LIBTOOL="$LIBTOOL"
 		else
 			dnl * build dynamic library of perl module
 			perl_module_lib=libperl_core.la
 			perl_module_fe_lib=libfe_perl.la
 			perl_static_lib=
 			perl_static_fe_lib=
-			PERL_LIBTOOL='$(SHELL) $(top_builddir)/libtool'
+			PERL_LIBTOOL="$LIBTOOL"
 		fi
 
 		if test "x$want_staticperllib" = "xyes"; then