diff --git a/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/changelog b/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/changelog
index 488db07c..ca9c6060 100644
--- a/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/changelog
+++ b/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/changelog
@@ -1,3 +1,9 @@
+pilot-link (0.12.5-dfsg-2debian13.0.0+3~a) trixie; urgency=medium
+
+  * Remove remaining 'register' instruction.
+
+ -- Slávek Banko <slavek.banko@axis.cz>  Tue, 16 Apr 2024 01:07:09 +0200
+
 pilot-link (0.12.5-dfsg-2debian12.0.0+2~a) bookworm; urgency=medium
 
   * Fix FTBFS due to syntax in configure.ac.
diff --git a/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/patches/remove-register-instruction.diff b/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/patches/remove-register-instruction.diff
new file mode 100644
index 00000000..9a57fe21
--- /dev/null
+++ b/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/patches/remove-register-instruction.diff
@@ -0,0 +1,274 @@
+Index: b/bindings/Python/src/pisock_wrap.c
+===================================================================
+--- a/bindings/Python/src/pisock_wrap.c
++++ b/bindings/Python/src/pisock_wrap.c
+@@ -335,14 +335,14 @@
+   swig_module_info *iter = start;
+   do {
+     if (iter->size) {
+-      register size_t l = 0;
+-      register size_t r = iter->size - 1;
++      size_t l = 0;
++      size_t r = iter->size - 1;
+       do {
+ 	/* since l+r >= 0, we can (>> 1) instead (/ 2) */
+-	register size_t i = (l + r) >> 1; 
++	size_t i = (l + r) >> 1;
+ 	const char *iname = iter->types[i]->name;
+ 	if (iname) {
+-	  register int compare = strcmp(name, iname);
++	  int compare = strcmp(name, iname);
+ 	  if (compare == 0) {	    
+ 	    return iter->types[i];
+ 	  } else if (compare < 0) {
+@@ -386,7 +386,7 @@
+        of the str field (the human readable name) */
+     swig_module_info *iter = start;
+     do {
+-      register size_t i = 0;
++      size_t i = 0;
+       for (; i < iter->size; ++i) {
+ 	if (iter->types[i]->str && (SWIG_TypeEquiv(iter->types[i]->str, name)))
+ 	  return iter->types[i];
+@@ -406,10 +406,10 @@
+ SWIGRUNTIME char *
+ SWIG_PackData(char *c, void *ptr, size_t sz) {
+   static const char hex[17] = "0123456789abcdef";
+-  register const unsigned char *u = (unsigned char *) ptr;
+-  register const unsigned char *eu =  u + sz;
++  const unsigned char *u = (unsigned char *) ptr;
++  const unsigned char *eu =  u + sz;
+   for (; u != eu; ++u) {
+-    register unsigned char uu = *u;
++    unsigned char uu = *u;
+     *(c++) = hex[(uu & 0xf0) >> 4];
+     *(c++) = hex[uu & 0xf];
+   }
+@@ -421,11 +421,11 @@
+ */
+ SWIGRUNTIME const char *
+ SWIG_UnpackData(const char *c, void *ptr, size_t sz) {
+-  register unsigned char *u = (unsigned char *) ptr;
+-  register const unsigned char *eu = u + sz;
++  unsigned char *u = (unsigned char *) ptr;
++  const unsigned char *eu = u + sz;
+   for (; u != eu; ++u) {
+-    register char d = *(c++);
+-    register unsigned char uu = 0;
++    char d = *(c++);
++    unsigned char uu = 0;
+     if ((d >= '0') && (d <= '9'))
+       uu = ((d - '0') << 4);
+     else if ((d >= 'a') && (d <= 'f'))
+Index: b/libpisock/md5.c
+===================================================================
+--- a/libpisock/md5.c
++++ b/libpisock/md5.c
+@@ -149,7 +149,7 @@
+  */
+ void MD5Transform(UINT32 buf[4], UINT32 const in[16])
+ {
+-	register UINT32 a, b, c, d;
++	UINT32 a, b, c, d;
+ 
+ 	a = buf[0];
+ 	b = buf[1];
+Index: b/libpisock/utils.c
+===================================================================
+--- a/libpisock/utils.c
++++ b/libpisock/utils.c
+@@ -122,8 +122,8 @@
+ int putenv(const char *string)
+ {
+ 	const char 	*const name_end = strchr(string, '=');
+-	register 	size_t size;
+-	register 	char **ep;
++	size_t size;
++	char **ep;
+ 
+ 	if (name_end == NULL) {
+ 		/* Remove the variable from the environment.  */
+@@ -204,12 +204,12 @@
+  ***********************************************************************/
+ int inet_aton(const char *cp, struct in_addr *addr)
+ {
+-	register u_long 	val;
+-	register int 		base;
+-	register int		n;
+-	register char 		c;
+-	u_int 			parts[4];
+-	register u_int 		*pp = parts;
++	u_long 	val;
++	int		base;
++	int		n;
++	char		c;
++	u_int			parts[4];
++	u_int		*pp = parts;
+ 
+ 	for (;;) {
+ 		/* Collect number up to ``.''. Values are specified as for
+Index: b/src/parsedate.c
+===================================================================
+--- a/src/parsedate.c
++++ b/src/parsedate.c
+@@ -282,7 +282,7 @@
+ #   define YYCOPY(To, From, Count)		\
+       do					\
+ 	{					\
+-	  register YYSIZE_T yyi;		\
++	  YYSIZE_T yyi;		\
+ 	  for (yyi = 0; yyi < (Count); yyi++)	\
+ 	    (To)[yyi] = (From)[yyi];		\
+ 	}					\
+@@ -723,7 +723,7 @@
+      const char *yystr;
+ #   endif
+ {
+-  register const char *yys = yystr;
++  const char *yys = yystr;
+ 
+   while (*yys++ != '\0')
+     continue;
+@@ -748,8 +748,8 @@
+      const char *yysrc;
+ #   endif
+ {
+-  register char *yyd = yydest;
+-  register const char *yys = yysrc;
++  char *yyd = yydest;
++  const char *yys = yysrc;
+ 
+   while ((*yyd++ = *yys++) != '\0')
+     continue;
+@@ -879,8 +879,8 @@
+ #endif
+ {
+   
+-  register int yystate;
+-  register int yyn;
++  int yystate;
++  int yyn;
+   int yyresult;
+   /* Number of tokens to shift before error messages enabled.  */
+   int yyerrstatus;
+@@ -898,12 +898,12 @@
+   /* The state stack.  */
+   short int yyssa[YYINITDEPTH];
+   short int *yyss = yyssa;
+-  register short int *yyssp;
++  short int *yyssp;
+ 
+   /* The semantic value stack.  */
+   YYSTYPE yyvsa[YYINITDEPTH];
+   YYSTYPE *yyvs = yyvsa;
+-  register YYSTYPE *yyvsp;
++  YYSTYPE *yyvsp;
+ 
+ 
+ 
+@@ -1821,10 +1821,10 @@
+ 	1972, 1976, 1980, 1984, 1988, 1992, 1996,
+ 	2000, 2004, 2008, 2012, 2016, 2020, 2024, 2028, 2032, 2036
+     };
+-    register int	*yp;
+-    register int	*mp;
+-    register time_t	Julian;
+-    register int	i;
++    int	*yp;
++    int	*mp;
++    time_t	Julian;
++    int	i;
+     time_t		tod;
+ 
+     if (Year < 0)
+@@ -1899,12 +1899,12 @@
+ static int
+ LookupWord(buff, length)
+     char		*buff;
+-    register int	length;
++    int	length;
+ {
+-    register char	*p;
+-    register char	*q;
+-    register TABLE	*tp;
+-    register int	c;
++    char	*p;
++    char	*q;
++    TABLE	*tp;
++    int	c;
+ 
+     p = buff;
+     c = p[0];
+@@ -1991,12 +1991,12 @@
+ int
+ date_lex()
+ {
+-    register char	c;
+-    register char	*p;
++    char	c;
++    char	*p;
+     char		buff[20];
+-    register int	sign;
+-    register int	i;
+-    register int	nesting;
++    int	sign;
++    int	i;
++    int	nesting;
+ 
+     for ( ; ; ) {
+ 	/* Get first character after the whitespace. */
+Index: b/src/parsedate.y
+===================================================================
+--- a/src/parsedate.y
++++ b/src/parsedate.y
+@@ -492,10 +492,10 @@
+ 	1972, 1976, 1980, 1984, 1988, 1992, 1996,
+ 	2000, 2004, 2008, 2012, 2016, 2020, 2024, 2028, 2032, 2036
+     };
+-    register int	*yp;
+-    register int	*mp;
+-    register time_t	Julian;
+-    register int	i;
++    int	*yp;
++    int	*mp;
++    time_t	Julian;
++    int	i;
+     time_t		tod;
+ 
+     if (Year < 0)
+@@ -570,12 +570,12 @@
+ static int
+ LookupWord(buff, length)
+     char		*buff;
+-    register int	length;
++    int	length;
+ {
+-    register char	*p;
+-    register char	*q;
+-    register TABLE	*tp;
+-    register int	c;
++    char	*p;
++    char	*q;
++    TABLE	*tp;
++    int	c;
+ 
+     p = buff;
+     c = p[0];
+@@ -662,12 +662,12 @@
+ int
+ date_lex()
+ {
+-    register char	c;
+-    register char	*p;
++    char	c;
++    char	*p;
+     char		buff[20];
+-    register int	sign;
+-    register int	i;
+-    register int	nesting;
++    int	sign;
++    int	i;
++    int	nesting;
+ 
+     for ( ; ; ) {
+ 	/* Get first character after the whitespace. */
diff --git a/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/patches/series b/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/patches/series
index dd62b305..82f5784b 100644
--- a/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/patches/series
+++ b/debian/pilot-link/pilot-link-0.12.5-dfsg/debian/patches/series
@@ -6,3 +6,4 @@ colourcorrect
 31_pilot-addresses.1
 0001-Don-t-use-PERL_POLLUTE-macros.patch
 0002-Fix-configure-syntax.patch
+remove-register-instruction.diff