Ass include of iec_std_lib.h in POUS.h file.
#!/bin/bash
# matiec - a compiler for the programming languages defined in IEC 61131-3
#
# Copyright (C) 2003-2011 Mario de Sousa (msousa@fe.up.pt)
# Copyright (C) 2007-2011 Laurent Bessard and Edouard Tisserant
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
#
# Shell script to build test for unix likes
STFILE=$1
shift
CFLAGS=$*
CC=gcc
#CC=i686-mingw32-gcc
../iec2c $STFILE -I ../lib
#2>/dev/null
$CC -I ../lib -c STD_RESSOURCE.c $CFLAGS
$CC -I ../lib -c STD_CONF.c $CFLAGS
$CC -I ../lib -c plc.c $CFLAGS
$CC -I ../lib main.c STD_CONF.o STD_RESSOURCE.o plc.o $CFLAGS -l rt -o test