diff --git a/lang/basic/src/basic.g b/lang/basic/src/basic.g
index bd94cf458..182ab2a73 100644
--- a/lang/basic/src/basic.g
+++ b/lang/basic/src/basic.g
@@ -90,6 +90,10 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include "bem.h"
+#include "util.h"
+#include "gencode.h"
+#include "eval.h"
+#include "func.h"
 #include "llmess.h"
 
 typedef union {
diff --git a/lang/basic/src/basic.lex b/lang/basic/src/basic.lex
index 3ee185e3f..11b3e2bf8 100644
--- a/lang/basic/src/basic.lex
+++ b/lang/basic/src/basic.lex
@@ -3,7 +3,8 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 
-#ifndef NORSCID
+
+#ifndef NORCSID
 static char rcs_lex[] = "$Id$" ;
 #endif
 
@@ -151,7 +152,7 @@ Key keywords [] ={
 int	kex[27];
 
 /* Initialize the keyword table */
-fillkex()
+void fillkex(void)
 {
 	Key *k;
 	int i;
@@ -235,7 +236,7 @@ File *stream;
     }
 }
 
-getinputline()
+int getinputline(void)
 {
 	/* get next input line */
 
@@ -255,7 +256,7 @@ getinputline()
 
 
 
-typechar()
+int typechar(void)
 {
 	switch(*cptr)
 	{
@@ -277,7 +278,7 @@ typechar()
 char name[SIGNIFICANT+1];
 
 
-lookup()
+int lookup(void)
 {
 	Key *k;
 	Symbol *Sym;
@@ -341,7 +342,7 @@ lookup()
 
 
 /* Parsing unsigned numbers */
-readconstant()
+int readconstant(void)
 {
 	/* read HEX and OCTAL numbers */
 	char *c;
@@ -372,9 +373,7 @@ readconstant()
 #ifdef ____
 /* Computes base to the power exponent. This was not done in the old
    compiler                                                          */
-double powr(base,exp)
-double base;
-int exp;
+double powr(double base,int exp)
 {
 	int i;
 	double result;
@@ -398,7 +397,7 @@ int exp;
 #endif
 
 
-number()
+int number(void)
 {
 	long	i1;
 	int overflow = 0;
@@ -468,7 +467,7 @@ number()
 
 
 
-scanstring()
+int scanstring(void)
 {
 	int i,length=0;
 	char firstchar = *cptr;
@@ -532,7 +531,7 @@ scanstring()
 
 
 
-yylex()
+int yylex(void)
 {
 	char *c;
 
diff --git a/lang/basic/src/bem.c b/lang/basic/src/bem.c
index b254051c2..b1cd73101 100644
--- a/lang/basic/src/bem.c
+++ b/lang/basic/src/bem.c
@@ -4,8 +4,12 @@
  */
 
 #include "bem.h"
+#include "parsepar.h"
+#include "system.h"
+#include "graph.h"
 
-#ifndef NORSCID
+
+#ifndef NORCSID
 static char rcs_id[]	= "$Id$" ;
 static char rcs_bem[]	= RCS_BEM ;
 static char rcs_symb[]	= RCS_SYMB ;
@@ -33,9 +37,11 @@ char	*inpfile, *outfile;
 int	BEMINTSIZE = EMINTSIZE;
 int	BEMPTRSIZE = EMPTRSIZE;
 int	BEMFLTSIZE = EMFLTSIZE;
-main(argc,argv)
-int argc;
-char **argv;
+
+extern void initialize(void);
+extern void compileprogram(void);
+
+int main(int argc,char **argv)
 {
 	extern int errorcnt;
 
diff --git a/lang/basic/src/bem.h b/lang/basic/src/bem.h
index a92cff0b8..bab52ba6c 100644
--- a/lang/basic/src/bem.h
+++ b/lang/basic/src/bem.h
@@ -4,13 +4,14 @@
  */
 
 #include <stdlib.h>
+#include <stdio.h>
 #include <ctype.h>
 #include <string.h>
 #include <signal.h>
-#include <system.h>
-#include <print.h>
-#include <em.h>
-#include <em_mes.h>
+#include "system.h"
+#include "print.h"
+#include "em.h"
+#include "em_mes.h"
 
 /* Author: M.L. Kersten
 ** Here all the global objects are defined.
diff --git a/lang/basic/src/compile.c b/lang/basic/src/compile.c
index eee685910..850e03c18 100644
--- a/lang/basic/src/compile.c
+++ b/lang/basic/src/compile.c
@@ -3,19 +3,25 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 
+/*#include "bem.h"*/
+#include <stdio.h>
+#include "system.h"
+#include "gencode.h"
 #include "bem.h"
 
-#ifndef NORSCID
+#ifndef NORCSID
 static char rcs_id[] = "$Id$" ;
 #endif
 
+extern int getinputline(void);
+extern void LLparse(void);
 
 /* compile the next program in the list */
 /* Here we should open the input file. (for the future) */
 
 File *yyin;
 
-compileprogram()
+void compileprogram(void)
 {
 	extern int basicline;
 
@@ -24,7 +30,9 @@ compileprogram()
                       epilogcode in the new version of the compiler */
 
 	while( basicline = 0, getinputline())
-		(void) LLparse();
+	{
+		LLparse();
+	}
 	epilogcode(); 	
 	sys_close(yyin);
 }
diff --git a/lang/basic/src/eval.c b/lang/basic/src/eval.c
index f1f762b05..c7edc0d9f 100644
--- a/lang/basic/src/eval.c
+++ b/lang/basic/src/eval.c
@@ -4,8 +4,10 @@
  */
 
 #include "bem.h"
+#include "util.h"
+#include "gencode.h"
 
-#ifndef NORSCID
+#ifndef NORCSID
 static char rcs_id[] = "$Id$" ;
 #endif
 
@@ -14,8 +16,7 @@ static char rcs_id[] = "$Id$" ;
    generate code for assignment statements
 */
 
-exprtype(ltype,rtype)
-int	ltype,rtype;
+static int exprtype(int ltype,int rtype)
 {
 	/* determine the result type of an expression */
 	if ( ltype==STRINGTYPE || rtype==STRINGTYPE)
@@ -31,9 +32,7 @@ int	ltype,rtype;
 
 
 
-void
-conversion(oldtype,newtype)
-int oldtype,newtype;
+void conversion(int oldtype,int newtype)
 {
 	/* the value on top of the stack should be converted */
 	if ( oldtype==newtype) return;
@@ -62,7 +61,10 @@ int oldtype,newtype;
 			C_lfr((arith)BEMINTSIZE);
 			break;
 		} else if ( newtype==FLOATTYPE || newtype==DOUBLETYPE)
+		{
 			break;
+		}
+		break;
 	default:
 		if (debug) 
 			print("type n=%d o=%d\n",newtype,oldtype);
@@ -72,9 +74,7 @@ int oldtype,newtype;
 
 
 
-void
-extraconvert(oldtype,newtype,topstack)
-int oldtype,newtype,topstack;
+void extraconvert(int oldtype,int newtype,int topstack)
 {
 	/* the value below the top of the stack should be converted */
 	if ( oldtype==newtype ) return;
@@ -116,8 +116,7 @@ int oldtype,newtype,topstack;
 
 	
 
-boolop(ltype,rtype,operator)
-int	ltype,rtype,operator;
+int boolop(int ltype,int rtype,int operator)
 {
 	if ( operator != NOTSYM)
 	{
@@ -158,8 +157,7 @@ int	ltype,rtype,operator;
 
 
 
-genbool(operator)
-int operator;
+void genbool(int operator)
 {
 	int l1,l2;
 
@@ -186,8 +184,7 @@ int operator;
 
 
 
-relop( ltype,rtype,operator)
-int	ltype,rtype,operator;
+int relop(int ltype,int rtype,int operator)
 {
 	int	result;
 
@@ -213,8 +210,7 @@ int	ltype,rtype,operator;
 
 
 
-plusmin(ltype,rtype,operator)
-int	ltype,rtype,operator;
+int plusmin(int ltype,int rtype,int operator)
 {
 	int result;
 
@@ -246,8 +242,7 @@ int	ltype,rtype,operator;
 
 
 
-muldiv(ltype,rtype,operator)
-int	ltype,rtype,operator;
+int muldiv(int ltype,int rtype,int operator)
 {
 	int result;
 
@@ -286,8 +281,7 @@ int	ltype,rtype,operator;
 
 
 
-negate(type)
-int type;
+int negate(int type)
 {
 	switch(type)
 	{
@@ -307,8 +301,7 @@ int type;
 
 
 #ifdef ___
-power(ltype,rtype)
-int	ltype,rtype;
+int power(int ltype,int rtype)
 {
 	int resulttype = exprtype(ltype, rtype);
 
@@ -330,8 +323,7 @@ int	ltype,rtype;
 	return(resulttype);
 }
 #else
-power(ltype,rtype)
-int	ltype,rtype;
+int power(int ltype,int rtype)
 {
 	extraconvert(ltype,DOUBLETYPE,rtype);
 	conversion(rtype,DOUBLETYPE);
@@ -343,8 +335,7 @@ int	ltype,rtype;
 #endif
 
 
-int typesize(ltype)
-int ltype;
+int typesize(int ltype)
 {
 	switch( ltype)
 	{
@@ -364,8 +355,7 @@ int ltype;
 
 
 
-int typestring(type)
-int type;
+int typestring(int type)
 {
 	switch(type)
 	{
@@ -384,8 +374,7 @@ int type;
 
 
 
-loadvar(type)
-int type;
+void loadvar(int type)
 {
 	/* load a simple variable  its address is on the stack*/
         C_loi((arith)typestring(type));
@@ -393,8 +382,7 @@ int type;
 
 
 
-loadint(value)
-int value;
+int loadint(int value)
 {
         C_loc((arith)value);
 	return(INTTYPE);
@@ -402,8 +390,7 @@ int value;
 
 
 
-loaddbl(value)
-char *value;
+int loaddbl(char* value)
 {
 	int index;
 
@@ -417,16 +404,14 @@ char *value;
 
 
 
-loadstr(value)
-int value;
+void loadstr(int value)
 {
 	C_lae_dlb((label)value,(arith)0);
 }
 
 
 
-loadaddr(s)
-Symbol *s;
+int loadaddr(Symbol *s)
 {
 	extern Symbol *fcn;
 	int i,j;
@@ -450,7 +435,7 @@ Symbol *s;
 
 
 /* This is a new routine */
-save_address()
+void save_address(void)
 {
 	C_lae_dnam("dummy3",(arith)0);
 	C_sti((arith)BEMPTRSIZE);
@@ -458,8 +443,7 @@ save_address()
 
 
 
-assign(type,lt)
-int type,lt;
+void assign(int type,int lt)
 {
 	extern int e1,e2;
 
@@ -472,8 +456,7 @@ int type,lt;
 
 
 
-storevar(lab,type)
-int lab,type;
+void storevar(int lab,int type)
 {
 	/*store value back */
 	C_lae_dlb((label)lab,(arith)0);
@@ -488,8 +471,7 @@ Symbol  *arraystk[MAXDIMENSIONS];
 
 
 
-newarrayload(s)
-Symbol *s;
+void newarrayload(Symbol *s)
 {
 	if ( dimtop<MAXDIMENSIONS) dimtop++;
 	if ( s->dimensions==0)
@@ -504,16 +486,14 @@ Symbol *s;
 
 
 
-endarrayload()
+int endarrayload(void)
 {
 	return(arraystk[dimtop--]->symtype);
 }
 
 
 
-void
-loadarray(type)
-int	type;
+void loadarray(int type)
 {
 	int	dim;
 	Symbol	*s;
diff --git a/lang/basic/src/eval.h b/lang/basic/src/eval.h
new file mode 100644
index 000000000..3bb71a18e
--- /dev/null
+++ b/lang/basic/src/eval.h
@@ -0,0 +1,54 @@
+/*  Copyright (c) 2019 ACK Project.
+ *  See the copyright notice in the ACK home directory,
+ *  in the file "Copyright".
+ *
+ */
+#ifndef __EVAL_H_INCLUDED__
+#define __EVAL_H_INCLUDED__
+
+#include "symbols.h"
+
+
+/*--------------------------- Utilities -----------------------*/
+
+/** From an internal type definition return the size in bytes of the data.
+ *  If not a known data type return an integer size. */
+extern int typesize(int ltype);
+/** From an internal type definition return the size in bytes of the data. If not a
+ *  known data type return a 0 size. */
+extern int typestring(int type);
+
+
+/*-------------------------- Code generation ---------------------*/
+
+/** Emit code to convert from the old internal type to the new internal type definition.
+ *  Generates an error if the type conversion is not allowed. */
+extern void conversion(int oldtype,int newtype);
+/** Emit code to store a value of the specified type from the top of stack
+ *  into the specified variable pointed to by label.
+ */
+extern void storevar(int lab,int type);
+
+/** Emit code to load a simple variable value on the stack. On input the address of the variable
+ *  is on the stack.  */
+extern void loadvar(int type);
+
+extern void extraconvert(int oldtype,int newtype,int topstack);
+
+extern void loadstr(int value);
+extern int endarrayload(void);
+extern void loadarray(int type);
+extern void save_address(void);
+extern void assign(int type,int lt);
+extern int boolop(int ltype,int rtype,int operator);
+extern int relop(int ltype,int rtype,int operator);
+extern int plusmin(int ltype,int rtype,int operator);
+extern int muldiv(int ltype,int rtype,int operator);
+extern int negate(int type);
+extern int power(int ltype,int rtype);
+extern int loadint(int value);
+extern int loaddbl(char* value);
+extern int loadaddr(Symbol *s);
+extern void newarrayload(Symbol *s);
+
+#endif /* __EVAL_H_INCLUDED */
diff --git a/lang/basic/src/func.c b/lang/basic/src/func.c
index f7510f994..d2e7456e6 100644
--- a/lang/basic/src/func.c
+++ b/lang/basic/src/func.c
@@ -4,8 +4,10 @@
  */
 
 #include "bem.h"
+#include "util.h"
+#include "eval.h"
 
-#ifndef NORSCID
+#ifndef NORCSID
 static char rcs_id[] = "$Id$" ;
 #endif
 
@@ -19,8 +21,7 @@ int	exprlimit;
 
 
 
-parm(cnt)
-int cnt;
+void parm(int cnt)
 {
 	if( cnt> exprlimit)
 		error("Not enough arguments");
@@ -30,9 +31,7 @@ int cnt;
 
 
 
-callfcn(fcnnr,cnt,typetable)
-int fcnnr,cnt;
-int *typetable;
+int callfcn(int fcnnr,int cnt,int *typetable)
 {
 	int pop=DOUBLETYPE;
 	int res=DOUBLETYPE;
diff --git a/lang/basic/src/func.h b/lang/basic/src/func.h
new file mode 100644
index 000000000..709d63e41
--- /dev/null
+++ b/lang/basic/src/func.h
@@ -0,0 +1,13 @@
+/*  Copyright (c) 2019 ACK Project.
+ *  See the copyright notice in the ACK home directory,
+ *  in the file "Copyright".
+ *
+ */
+#ifndef __FUNC_H_INCLUDED__
+#define __FUNC_H_INCLUDED__
+
+
+extern int callfcn(int fcnnr,int cnt,int *typetable);
+
+
+#endif /* __FUNC_H_INCLUDED__ */
diff --git a/lang/basic/src/gencode.c b/lang/basic/src/gencode.c
index 6a500d06d..3f920c483 100644
--- a/lang/basic/src/gencode.c
+++ b/lang/basic/src/gencode.c
@@ -4,9 +4,12 @@
  */
 
 #include "bem.h"
-#include "system.h"
+#include "graph.h"
+#include "eval.h"
+#include "util.h"
+#include "gencode.h"
 
-#ifndef NORSCID
+#ifndef NORCSID
 static char rcs_id[] = "$Id$" ;
 #endif
 
@@ -18,14 +21,14 @@ label	err_goto_label;
 
 
 
-genlabel()
+int genlabel(void)
 {
 	 return(emlabel++);
 }
 
 
 
-genemlabel()
+int genemlabel(void)
 {
 	int l;
 
@@ -39,8 +42,7 @@ genemlabel()
 
 
 int tronoff=0;
-newemblock(nr)
-int nr;
+void newemblock(int nr)
 {
 	C_df_ilb((label)currline->emlabel);
 	C_lin((arith)nr);
@@ -57,7 +59,7 @@ int nr;
 
 /* Handle data statements */
 List	*datalist=0;
-datastmt()
+void datastmt(void)
 {
 	List *l,*l1;
 
@@ -78,7 +80,7 @@ datastmt()
 
 
 
-datatable()
+void datatable(void)
 {
 	List *l;
 	int line=0;
@@ -100,8 +102,7 @@ datatable()
 
 
 /* ERROR and exception handling */
-exceptstmt(lab)
-int lab;
+void exceptstmt(int lab)
 {
 	/* exceptions to subroutines are supported only */
 	extern int gosubcnt;
@@ -116,8 +117,7 @@ int lab;
 
 
 
-errorstmt(exprtype)
-int	exprtype;
+void errorstmt(int exprtype)
 {
 	/* convert expression to a valid error number */
 	/* obtain the message and print it */
@@ -128,8 +128,7 @@ int	exprtype;
 
 
 /* BASIC IO */
-openstmt(recsize)
-int recsize;
+void openstmt(int recsize)
 {
 	C_loc((arith)recsize);
 	C_cal("_opnchn");
@@ -138,8 +137,7 @@ int recsize;
 
 
 
-printstmt(exprtype)
-int	exprtype;
+void printstmt(int exprtype)
 {
 	switch(exprtype)
 	{
@@ -165,16 +163,14 @@ int	exprtype;
 
 
 
-zone(i)
-int i;
+void zone(int i)
 {
 	if ( i) C_cal("_zone");
 }
 
 
 
-writestmt(exprtype,comma)
-int	exprtype,comma;
+void writestmt(int exprtype, int comma)
 {
 	if ( comma) C_cal("_wrcomma");
 
@@ -198,8 +194,7 @@ int	exprtype,comma;
 
 
 
-restore(lab)
-int lab;
+void restore(int lab)
 {
 	/* save this information too */
 
@@ -213,8 +208,7 @@ int lab;
 
 
 
-prompt(qst)
-int qst;
+void prompt(int qst)
 {
 	setchannel(-1);
 	C_cal("_prstr");
@@ -224,8 +218,7 @@ int qst;
 
 
 
-linestmt(type)
-int type;
+void linestmt(int type)
 {
 	if ( type!= STRINGTYPE)
 		error("String variable expected");
@@ -235,8 +228,7 @@ int type;
 
 
 
-readelm(type)
-int type;
+void readelm(int type)
 {
 	switch(type)
 	{
@@ -259,8 +251,7 @@ int type;
 
 
 /* Swap exchanges the variable values */
-swapstmt(ltype,rtype)
-int	ltype, rtype;
+void swapstmt(int ltype,int rtype)
 {
 	if ( ltype!= rtype)
 		error("Type mismatch");
@@ -287,9 +278,9 @@ int	ltype, rtype;
 
 
 /* input/output handling */
-setchannel(val)
-int val;
-{	/* obtain file descroption */
+void setchannel(int val)
+{
+	/* obtain file descroption */
 	C_loc((arith)val);
 	C_cal("_setchan");
 	C_asp((arith)BEMINTSIZE);
@@ -298,8 +289,7 @@ int val;
 
 
 /* The if-then-else statements */
-ifstmt(type)
-int type;
+int ifstmt(int type)
 {
 	/* This BASIC follows the True= -1 rule */
 	int nr;
@@ -322,8 +312,7 @@ int type;
 
 
 
-thenpart( elselab)
-int elselab;
+int thenpart(int elselab)
 {
 	int nr;
 
@@ -335,7 +324,7 @@ int elselab;
 
 
 
-elsepart(lab)int lab;
+void elsepart(int lab)
 {
 	C_df_ilb((label)lab);
 }
@@ -359,8 +348,7 @@ int	forcnt= -1;
 
 
 
-forinit(s)
-Symbol *s;
+void forinit(Symbol *s)
 {
 	int type;
 	struct FORSTRUCT *f;
@@ -388,8 +376,7 @@ Symbol *s;
 
 
 
-forexpr(type)
-int type;
+void forexpr(int type)
 {
 	/* save start value of loop variable in a save place*/
 	/* to avoid clashing with final value and step expression */
@@ -402,8 +389,7 @@ int type;
 
 
 
-forlimit(type)
-int type;
+void forlimit(int type)
 {
 	/* save the limit value too*/
 	int result;
@@ -415,8 +401,7 @@ int type;
 
 
 
-forskipped(f)
-struct FORSTRUCT *f;
+void forskipped(struct FORSTRUCT *f)
 {
 	int type;
 
@@ -452,8 +437,7 @@ struct FORSTRUCT *f;
 
 
 
-forstep(type)
-int type;
+void forstep(int type)
 {
 	int result;
 	int varaddress;
@@ -522,8 +506,7 @@ int type;
 
 
 
-nextstmt(s)
-Symbol *s;
+void nextstmt(Symbol *s)
 {
 	if (forcnt>MAXFORDEPTH || forcnt<0 || 
 	    (s && s!= fortable[forcnt].loopvar))
@@ -538,8 +521,7 @@ Symbol *s;
 
 
 
-pokestmt(type1,type2)
-int	type1,type2;
+void pokestmt(int type1,int type2)
 {
 	conversion(type1,INTTYPE);
 	conversion(type2,INTTYPE);
@@ -553,7 +535,7 @@ int	type1,type2;
 
 int	whilecnt, whilelabels[MAXDEPTH][2]; /*0=head,1=out */
 
-whilestart()
+void whilestart(void)
 {
 	whilecnt++;
 	if ( whilecnt==MAXDEPTH)
@@ -567,8 +549,7 @@ whilestart()
 
 
 
-whiletst(exprtype)
-int exprtype;
+void whiletst(int exprtype)
 {
 	/* test expression type */
 	conversion(exprtype,INTTYPE);
@@ -577,7 +558,7 @@ int exprtype;
 
 
 
-wend()
+void wend(void)
 {
 	if ( whilecnt<1)
 		error("not part of while statement");
@@ -591,7 +572,7 @@ wend()
 
 
 /* generate code for the final version */
-prologcode()
+void prologcode(void)
 {
 	/* generate the EM prolog code */
 	C_df_dnam("fltnull");
@@ -623,7 +604,7 @@ prologcode()
 
 
 
-prolog2()
+void prolog2(void)
 {
 	int result;
 	label l = genlabel(), l2;
@@ -659,7 +640,7 @@ prolog2()
 
 
 /* NEW */
-gendata() 
+void gendata(void)
 {
 	C_loc((arith)0);
 	C_cal("_setchan");
@@ -685,7 +666,7 @@ gendata()
 
 
 
-epilogcode()
+void epilogcode(void)
 {
 	/* finalization code */
 	int nr;
diff --git a/lang/basic/src/gencode.h b/lang/basic/src/gencode.h
new file mode 100644
index 000000000..ae59dc4b7
--- /dev/null
+++ b/lang/basic/src/gencode.h
@@ -0,0 +1,64 @@
+/*  Copyright (c) 2019 ACK Project.
+ *  See the copyright notice in the ACK home directory,
+ *  in the file "Copyright".
+ *
+ */
+#ifndef __GENCODE_H_INCLUDED__
+#define __GENCODE_H_INCLUDED__
+
+#include "symbols.h"
+
+
+/*--------------------------- Utilities -----------------------*/
+
+/** Return a global value identifier used for code generation */
+extern int genlabel(void);
+
+
+/*-------------------------- Code generation ---------------------*/
+
+/** Emit a label definition and return the label identifier generated. */
+extern int genemlabel(void);
+
+
+void newemblock(int nr);
+void newblock(int nr);
+void datastmt(void);
+void datatable(void);
+/* ERROR and exception handling */
+void exceptstmt(int lab);
+void errorstmt(int exprtype);
+/* BASIC IO */
+void openstmt(int recsize);
+void printstmt(int exprtype);
+void zone(int i);
+void writestmt(int exprtype, int comma);
+void restore(int lab);
+void prompt(int qst);
+void linestmt(int type);
+void readelm(int type);
+/* Swap exchanges the variable values */
+void swapstmt(int ltype,int rtype);
+void setchannel(int val);
+int ifstmt(int type);
+int thenpart(int elselab);
+void elsepart(int lab);
+void forinit(Symbol *s);
+void forexpr(int type);
+void forlimit(int type);
+void forstep(int type);
+void nextstmt(Symbol *s);
+void pokestmt(int type1,int type2);
+void whilestart(void);
+void whiletst(int exprtype);
+void wend(void);
+/* generate code for the final version */
+void prologcode(void);
+void prolog2(void);
+void gendata(void);
+void epilogcode(void);
+void setchannel(int val);
+void gendata(void);
+
+
+#endif /* __GENCODE_H_INCLUDED__ */
diff --git a/lang/basic/src/graph.c b/lang/basic/src/graph.c
index a960659b7..ed037ad82 100644
--- a/lang/basic/src/graph.c
+++ b/lang/basic/src/graph.c
@@ -4,8 +4,11 @@
  */
 
 #include "bem.h"
+#include "util.h"
+#include "eval.h"
+#include "gencode.h"
 
-#ifndef NORSCID
+#ifndef NORCSID
 static char rcs_id[] = "$Id$" ;
 #endif
 
@@ -18,7 +21,7 @@ Linerecord	*firstline,
 
 
 
-List *newlist()
+List *newlist(void)
 {
 	List *l;
 
@@ -29,8 +32,7 @@ List *newlist()
 
 /* Line management is handled here */
 
-Linerecord *srchline(nr)
-int nr;
+Linerecord *srchline(int nr)
 {
 	Linerecord *l;
 
@@ -41,8 +43,7 @@ int nr;
 
 
 
-List *srchforward(nr)
-int nr;
+List *srchforward(int nr)
 {
 	List *l;
 
@@ -53,7 +54,7 @@ int nr;
 
 
 
-linewarnings()
+void linewarnings(void)
 {
 	List *l;
 	extern int errorcnt;
@@ -72,8 +73,7 @@ linewarnings()
 
 
 
-newblock(nr)
-int	nr;
+void newblock(int nr)
 {
 	Linerecord	*l;
 	List		*frwrd;
@@ -111,8 +111,7 @@ int	nr;
 
 
 
-gotolabel(nr)
-int nr;
+int gotolabel(int nr)
 {
 	/* simulate a goto statement in the line record table */
 	Linerecord *l1;
@@ -146,8 +145,7 @@ int nr;
 
 
 
-gotostmt(nr)
-int nr;
+void gotostmt(int nr)
 {
            C_bra((label) gotolabel(nr));
 }
@@ -160,7 +158,7 @@ int	gosubcnt=1;
 
 
 
-List *gosublabel()
+List *gosublabel(void)
 {
 	List *l;
 
@@ -177,8 +175,7 @@ List *gosublabel()
 
 
 
-gosubstmt(lab)
-int lab;
+void gosubstmt(int lab)
 {
 	List *l;
 	int nr,n;
@@ -197,7 +194,7 @@ int lab;
 
 
 
-genreturns()
+void genreturns(void)
 {
 	int count;
 	int nr;
@@ -227,7 +224,7 @@ genreturns()
 
 
 
-returnstmt()
+void returnstmt(void)
 {
         C_cal("_retstmt");
         C_lfr((arith) BEMINTSIZE);
@@ -242,8 +239,7 @@ List	*jumphead,*jumptail;
 int	jumpcnt;
 
 
-jumpelm(nr)
-int nr;
+void jumpelm(int nr)
 {
 	List *l;
 
@@ -260,8 +256,7 @@ int nr;
 
 
 
-ongotostmt(type)
-int type;
+void ongotostmt(int type)
 {
 	/* generate the code itself, index in on top of the stack */
 	/* blurh, store the number of entries in the descriptor */
@@ -294,8 +289,7 @@ int type;
 
 
 
-ongosubstmt(type)
-int type;
+void ongosubstmt(int type)
 {
 	List *l;
 	int firstlabel;
diff --git a/lang/basic/src/graph.h b/lang/basic/src/graph.h
index ed0c05003..3bffd5d8b 100644
--- a/lang/basic/src/graph.h
+++ b/lang/basic/src/graph.h
@@ -3,6 +3,9 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 
+#ifndef  __GRAPH_H_INCLUDED__
+#define  __GRAPH_H_INCLUDED__
+
 #ifndef NORCSID
 # define RCS_GRAPH	"$Id$"
 #endif
@@ -35,3 +38,18 @@ extern Linerecord	*firstline,
 extern List	*forwardlabel;
 
 extern List	*gosublabel();
+extern void jumpelm(int nr);
+extern int gotolabel(int nr);
+extern void linewarnings(void);
+
+/*-------------------------- Code generation ---------------------*/
+
+
+extern void genreturns(void);
+extern void gosubstmt(int lab);
+extern void gotostmt(int nr);
+extern void returnstmt(void);
+extern void ongosubstmt(int type);
+extern void ongotostmt(int type);
+
+#endif
diff --git a/lang/basic/src/initialize.c b/lang/basic/src/initialize.c
index ce77ccf35..d8838551e 100644
--- a/lang/basic/src/initialize.c
+++ b/lang/basic/src/initialize.c
@@ -3,9 +3,11 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 
+#include <stdio.h>
 #include "bem.h"
+#include "util.h"
 
-#ifndef NORSCID
+#ifndef NORCSID
 static char rcs_id[] = "$Id$";
 #endif
 
@@ -13,9 +15,9 @@ static char rcs_id[] = "$Id$";
 
 File	*datfile;
 
+extern void fillkex(void);
 
-
-initialize()
+void initialize(void)
 {
 	register char *cindex, *cptr;
         int result1, result2;
@@ -33,7 +35,7 @@ initialize()
 		}
 	}
 	cptr=datfname;
-	while ( *cptr++ = *cindex++ );
+	while ( (*cptr++ = *cindex++) !=0 );
 	/* Strip trailing suffix */
 	if ( cptr>datfname+3 && cptr[-3]=='.' ) cptr[-3]=0;
 	strcat(datfname,".d");
diff --git a/lang/basic/src/llmess.h b/lang/basic/src/llmess.h
index ec96261ef..39c3722d1 100644
--- a/lang/basic/src/llmess.h
+++ b/lang/basic/src/llmess.h
@@ -3,16 +3,17 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 
+#include <stdio.h>
 #include "tokentab.h"
+#include "system.h"
+#include "print.h"
 
 /* Mod van gertjan */
 extern int LLsymb;
 extern int toknum;
 
 
-error_char(format,ch)
-char *format;
-char ch;
+void error_char(char *format,char ch)
 {
 	extern int listing,errorcnt;
 	extern int basicline;
@@ -24,9 +25,7 @@ char ch;
 
 
 
-error_string(format,str)
-char *format;
-char *str;
+void error_string(char* format,char* str)
 {
 	extern int listing,errorcnt;
 	extern int basicline;
@@ -38,8 +37,7 @@ char *str;
 
 
 
-LLmessage( insertedtok )
-int insertedtok;
+void LLmessage(int insertedtok )
 {
     if ( insertedtok < 0 ) {
 	error("Fatal stack overflow\n");
diff --git a/lang/basic/src/options b/lang/basic/src/options
new file mode 100644
index 000000000..7b60cd1b4
--- /dev/null
+++ b/lang/basic/src/options
@@ -0,0 +1,11 @@
+User options:
+D	parser debugging
+t	line tracing
+d	debug information
+E	generate full listing
+L	don't generate linenumbers and filename indications
+w	suppress warning diagnostics
+VwN	set word size to N bytes	
+VpN set pointer size to N bytes
+VfN	set real size to N bytes
+			
\ No newline at end of file
diff --git a/lang/basic/src/parsepar.c b/lang/basic/src/parsepar.c
index 0194c6526..32ee177db 100644
--- a/lang/basic/src/parsepar.c
+++ b/lang/basic/src/parsepar.c
@@ -3,9 +3,15 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 
+#include "parsepar.h"
 #include "bem.h"
+#include <stdio.h>
+#include "print.h"
+#include "system.h"
+#include "util.h"
 
-#ifndef NORSCID
+
+#ifndef NORCSID
 static char rcs_id[] = "$Id$" ;
 #endif
 
@@ -18,9 +24,7 @@ int	nolins=0;		/* generate no LIN statements */
 
 
 
-parseparams(argc,argv)
-int argc;
-char **argv;
+void parseparams(int argc,char **argv)
 {
 	int files=0 ;
 	int i;
diff --git a/lang/basic/src/parsepar.h b/lang/basic/src/parsepar.h
new file mode 100644
index 000000000..e5e1fa52f
--- /dev/null
+++ b/lang/basic/src/parsepar.h
@@ -0,0 +1,23 @@
+/*  Copyright (c) 2019 ACK Project.
+ *  See the copyright notice in the ACK home directory,
+ *  in the file "Copyright".
+ *
+ */
+#ifndef __PARSEPAR_H_INCLUDED__
+#define __PARSEPAR_H_INCLUDED__
+
+/** -l listing required */
+extern int	listing;
+/** -d compiler debugging */
+extern int	debug;
+/** -w warning flags */
+extern int	wflag;
+/** generate line tracing code. */
+extern int	traceflag;
+/** generate LIN statements */
+extern int	nolins;
+
+
+void parseparams(int argc,char **argv);
+
+#endif /* __PARSEPAR_H_INCLUDED__ */
diff --git a/lang/basic/src/symbols.c b/lang/basic/src/symbols.c
index 96d148ae3..2551ece45 100644
--- a/lang/basic/src/symbols.c
+++ b/lang/basic/src/symbols.c
@@ -3,9 +3,18 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 
+#include "symbols.h"
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
 #include "bem.h"
+#include "eval.h"
+#include "gencode.h"
+#include "util.h"
 
-#ifndef NORSCID
+
+
+#ifndef NORCSID
 static char rcs_id[] = "$Id$" ;
 #endif
 
@@ -15,7 +24,11 @@ int	deftype[128];		/* default type declarer */
 				/* which may be set by OPTION BASE */
 
 
-initdeftype()
+/* Local declarations */
+static void get_space(int type,int size);
+
+
+void initdeftype(void)
 {
 	int i;
 
@@ -31,8 +44,7 @@ Symbol *alternate = NIL;
 
 
 
-Symbol *srchsymbol(str)
-char *str;
+Symbol *srchsymbol(char* str)
 {
 	Symbol *s;
 
@@ -68,9 +80,7 @@ char *str;
 
 
 
-void
-dcltype(s)
-Symbol *s;
+void dcltype(Symbol *s)
 {
 	/* type declarer */
 	int type;
@@ -79,7 +89,7 @@ Symbol *s;
 	type=s->symtype;
 	if (type==DEFAULTTYPE)
 		/* use the default rule */
-		type= deftype[*s->symname];
+		type= deftype[(int)(*s->symname)];
 	/* generate the emlabel too */
 	if ( s->symalias==0)
 		s->symalias= dclspace(type);
@@ -89,8 +99,7 @@ Symbol *s;
 
 
 
-dclarray(s)
-Symbol *s;
+void dclarray(Symbol *s)
 {
 	int i; int size;
 
@@ -122,8 +131,7 @@ Symbol *s;
 
 
 
-get_space(type,size)
-int type,size;
+static void get_space(int type,int size)
 {
 
 	switch ( type ) {
@@ -153,8 +161,7 @@ int type,size;
 
 
 
-defarray(s)
-Symbol *s;
+void defarray(Symbol *s)
 {
 	/* array is used without dim statement, set default limits */
 	int i;
@@ -164,7 +171,7 @@ Symbol *s;
 
 
 
-dclspace(type)
+int dclspace(int type)
 {
 	int nr;
 
@@ -189,8 +196,7 @@ dclspace(type)
 
 
 /* SOME COMPILE TIME OPTIONS */
-optionbase(ival)
-int	ival;
+void optionbase(int ival)
 {
 	if ( ival<0 || ival>1)
 		error("illegal option base value");
@@ -199,8 +205,7 @@ int	ival;
 
 
 
-setdefaulttype(type)
-int	type;
+void setdefaulttype(int type)
 {
 	extern char *cptr;
 	char	first,last,i;
@@ -233,8 +238,7 @@ Symbol *fcn;
 
 
 
-newscope(s)
-Symbol *s;
+void newscope(Symbol *s)
 {
 	if (debug) print("new scope for %s\n",s->symname);
 	alternate= firstsym;
@@ -253,7 +257,7 @@ Symbol *s;
 
 
 
-heading( )
+void heading(void)
 {
 	char procname[50];
 
@@ -265,7 +269,7 @@ heading( )
 
 
 
-int fcnsize()
+static int fcnsize(void)
 {
 	/* generate portable function size */
 	int	i,sum;  /* sum is NEW */
@@ -278,8 +282,7 @@ int fcnsize()
 
 
 
-endscope(type)
-int type;
+void endscope(int type)
 {
 	Symbol *s;
 
@@ -304,8 +307,7 @@ int type;
 
 
 
-dclparm(s)
-Symbol	*s;
+void dclparm(Symbol *s)
 {
 	int size=0;
 
@@ -327,8 +329,7 @@ int	fcnindex= -1;
 
 
 
-fcncall(s)
-Symbol *s;
+int fcncall(Symbol *s)
 {
 	if ( !s->isfunction)
 		error("Function not declared");
@@ -342,8 +343,7 @@ Symbol *s;
 
 
 
-fcnend(parmcount)
-int parmcount;
+int fcnend(int parmcount)
 {
 	int type;
 	static char concatbuf[50]; /* NEW */
@@ -366,8 +366,7 @@ int parmcount;
 
 
 
-callparm(ind,type)
-int ind,type;
+void callparm(int ind,int type)
 {
 	if ( fcnindex<0) error("unexpected parameter");
 	if ( ind >= fcn->dimensions)
diff --git a/lang/basic/src/symbols.h b/lang/basic/src/symbols.h
index 358dd3359..c0c0b615d 100644
--- a/lang/basic/src/symbols.h
+++ b/lang/basic/src/symbols.h
@@ -3,6 +3,9 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 
+#ifndef __SYMBOLS_H_INCLUDED__
+#define __SYMBOLS_H_INCLUDED__
+
 #ifndef NORCSID
 # define RCS_SYMB	"$Id$"
 #endif
@@ -85,4 +88,21 @@ typedef struct SYMBOL{
 	int	isparam;
 } Symbol;
 
-extern	Symbol *srchsymbol();
+void initdeftype(void);
+Symbol *srchsymbol(char* str);
+void dcltype(Symbol *s);
+void dclarray(Symbol *s);
+void defarray(Symbol *s);
+int dclspace(int type);
+void optionbase(int ival);
+void setdefaulttype(int type);
+void newscope(Symbol *s);
+void heading(void);
+void endscope(int type);
+void dclparm(Symbol *s);
+int fcncall(Symbol *s);
+int fcnend(int parmcount);
+void callparm(int ind,int type);
+
+#endif /* __SYMBOLS_H_INCLUDED__ */
+
diff --git a/lang/basic/src/util.c b/lang/basic/src/util.c
index a85339bc5..d300431a1 100644
--- a/lang/basic/src/util.c
+++ b/lang/basic/src/util.c
@@ -3,9 +3,12 @@
  * See the copyright notice in the ACK home directory, in the file "Copyright".
  */
 
+#include "system.h"
+#include "util.h"
 #include "bem.h"
 
-#ifndef NORSCID
+
+#ifndef NORCSID
 static char rcs_id[] = "$Id$" ;
 #endif
 
@@ -16,25 +19,8 @@ int	errorcnt;
 
 
 
-void
-warning(str)
-char *str;
-{
-	 if (wflag) return;
-	 Xerror("WARNING", str);
-}
 
-
-error(str)
-char *str;
-{
-	Xerror("ERROR", str);
-	errorcnt++;
-}
-
-Xerror(type, str)
-char *str;
-char *type;
+static void Xerror(char *type, char *str)
 {
 	extern int listing;
 	extern int basicline;
@@ -45,8 +31,23 @@ char *type;
 
 
 
-fatal(str)
-char *str;
+
+void warning(char* str)
+{
+	 if (wflag) return;
+	 Xerror("WARNING", str);
+}
+
+
+void error(char* str)
+{
+	Xerror("ERROR", str);
+	errorcnt++;
+}
+
+
+
+void fatal(char* str)
 {
 	Xerror("FATAL",str);
 	C_close();
@@ -55,22 +56,21 @@ char *str;
 
 
 
-notyetimpl()
+void notyetimpl(void)
 {
 	warning("not yet implemented");
 }
 
 
 
-illegalcmd()
+void illegalcmd(void)
 {
 	warning("illegal command");
 }
 
 
 
-char *myitoa(i)
-int i;
+char *myitoa(int i)
 {
 	static char buf[30];
 
@@ -79,12 +79,7 @@ int i;
 }
 
 
-
-
-
-
-char *salloc(length)
-unsigned length;
+char *salloc(unsigned int length)
 {		
 	char *s,*c;
 
diff --git a/lang/basic/src/util.h b/lang/basic/src/util.h
new file mode 100644
index 000000000..f3c754439
--- /dev/null
+++ b/lang/basic/src/util.h
@@ -0,0 +1,32 @@
+/*  Copyright (c) 2019 ACK Project.
+ *  See the copyright notice in the ACK home directory,
+ *  in the file "Copyright".
+ *
+ */
+#ifndef __UTIL_H_INCLUDED__
+#define __UTIL_H_INCLUDED__
+
+/** Raises a warning with the specified message. */
+void warning(char* str);
+/** Raises a non fatal error with the specified message. */
+void error(char* str);
+/** Raises a fatal error with the specified message and
+    quits the application. */
+void fatal(char* str);
+/** Error management to raise a warning on an unimplemented
+ *  feature. */
+void notyetimpl(void);
+/** Error management to raise a warning on an illegal command
+    line option. */
+void illegalcmd(void);
+
+
+char *myitoa(int i);
+
+/** Tries to allocates a memory block of the specified number of bytes, and exits
+ *  with a fatal error upon a failure. Upon allocation success, fills the allocated
+ *  memory block with binary 0.
+ */
+char *salloc(unsigned int length);
+
+#endif /* __UTIL_H_INCLUDED__ */
diff --git a/lang/basic/src/yylexp.h b/lang/basic/src/yylexp.h
index a1b1ba01d..5f6b23808 100644
--- a/lang/basic/src/yylexp.h
+++ b/lang/basic/src/yylexp.h
@@ -5,7 +5,9 @@
 
 int toknum;
 
-yylexp() 
+extern int yylex(void);
+
+int yylexp(void)
 {
 /* als toknum != 0 dan bevat toknum een door LLmessage back-ge-pushed token */