see https://bugs.gentoo.org/943915
fix c23, old-style def
--- a/src/loki91.c
+++ b/src/loki91.c
@@ -61,10 +61,10 @@
 
 #define	MSB	0x80000000L		/* MSB of 32-bit word */
 
-void perm32(out, in , perm)
-Long	*out;		/* Output 32-bit block to be permuted                */
-Long	*in;		/* Input  32-bit block after permutation             */
-char	perm[32]; 	/* Permutation array                                 */
+void perm32(Long *out, Long *in, char perm[32])
+/*Long	*out;		Output 32-bit block to be permuted                */
+/*Long	*in;		Input  32-bit block after permutation             */
+/*char	perm[32]; 	Permutation array                                 */
 {
 	Long	mask = MSB;		/* mask used to set bit in output    */
 	register int	i, o, b;	/* input bit no, output bit no, value */
@@ -89,9 +89,9 @@ char	perm[32]; 	/* Permutation array                                 */
 
 #define SIZE 256		/* 256 elements in GF(2^8) */
 
-short mult8(a, b, gen)
-short	a, b;		/* operands for multiply */
-short	gen;		/* irreducible polynomial generating Galois Field */
+short mult8(short a, short b, short gen)
+/*short	a, b;		operands for multiply */
+/*short	gen;		irreducible polynomial generating Galois Field */
 {
 	short	product = 0;		/* result of multiplication */
 
@@ -112,10 +112,10 @@ short	gen;		/* irreducible polynomial generating Galois Field */
  *			exp = base ^ exp mod gen
  */
 
-short exp8(base, exponent, gen)
-short	base;		/* base of exponentiation 	*/
-short	exponent;	/* exponent			*/
-short	gen;		/* irreducible polynomial generating Galois Field */
+short exp8(short base, short exponent, short gen)
+/*short	base;		base of exponentiation 	*/
+/*short	exponent;	exponent			*/
+/*short	gen;		irreducible polynomial generating Galois Field */
 {
 	short	accum = base;	/* superincreasing sequence of base */
 	short	result = 1;	/* result of exponentiation	    */
@@ -139,8 +139,8 @@ short	gen;		/* irreducible polynomial generating Galois Field */
 char	*loki_lib_ver = "LOKI91 library v3.0, Copyright (C) 1991 Lawrence Brown & UNSW";
 
 		/* subkeys at the 16 rounds */
-static Long	f();			/* declare LOKI function f */
-static short	s();			/* declare LOKI S-box fn s */
+static Long	f(register Long r, Long k);			/* declare LOKI function f */
+static short	s(register Long i);			/* declare LOKI S-box fn s */
 
 
 /*
@@ -270,9 +270,9 @@ deloki(Long loki_subkeys[ROUNDS], char b[LOKIBLK])
 #define MASK12	0x0fff			/* 12 bit mask for expansion E */
 
 static Long
-f(r, k)
-register Long	r;	/* Data value R(i-1) */
-Long		k;	/* Key     K(i)   */
+f(register Long r, Long k)
+/*register Long	r;	Data value R(i-1) */
+/*Long		k;	Key     K(i)   */
 {
 	Long	a, b, c;		/* 32 bit S-box output, & P output */
 
@@ -298,11 +298,10 @@ Long		k;	/* Key     K(i)   */
 /*
  *	s(i) - return S-box value for input i
  */
-static short s(i)
-register Long i;	/* return S-box value for input i */
+static short s(register Long i)
+/*register Long i;	return S-box value for input i */
 {
 	register short	r, c, v, t;
-	short	exp8();		/* exponentiation routine for GF(2^8) */
 
 	r = ((i>>8) & 0xc) | (i & 0x3);		/* row value-top 2 & bottom 2 */
 	c = (i>>2) & 0xff;			/* column value-middle 8 bits */
--- a/src/seal.c
+++ b/src/seal.c
@@ -46,10 +46,7 @@ typedef struct {
 #define F3(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
 #define F4(x, y, z) ((x) ^ (y) ^ (z))
 
-int g(in,i,h)
-unsigned char *in;
-int i;
-uint32_t *h;
+int g(unsigned char *in, int i, uint32_t *h)
 {
 
 uint32_t h0,h1,h2,h3,h4,a,b,c,d,e,temp;