diff --git a/usr.bin/lex/ccl.c b/usr.bin/lex/ccl.c
index 025a914407ec..f2607bfa9094 100644
--- a/usr.bin/lex/ccl.c
+++ b/usr.bin/lex/ccl.c
@@ -122,7 +122,7 @@ void list_character_set( file, cset )
 FILE *file;
 int cset[];
 	{
-	register int i;
+	int i;
 
 	putc( '[', file );
 
@@ -130,7 +130,7 @@ int cset[];
 		{
 		if ( cset[i] )
 			{
-			register int start_char = i;
+			int start_char = i;
 
 			putc( ' ', file );
 
diff --git a/usr.bin/lex/dfa.c b/usr.bin/lex/dfa.c
index 0853466f9ac2..5a86af16a344 100644
--- a/usr.bin/lex/dfa.c
+++ b/usr.bin/lex/dfa.c
@@ -105,13 +105,13 @@ int *nfa_states, num_states;
 int *accset;
 int nacc;
 	{
-	register int i, j;
+	int i, j;
 
 	for ( i = 1; i <= num_states; ++i )
 		{
 		int ns = nfa_states[i];
-		register int type = state_type[ns];
-		register int ar = assoc_rule[ns];
+		int type = state_type[ns];
+		int ar = assoc_rule[ns];
 
 		if ( type == STATE_NORMAL || rule_type[ar] != RULE_VARIABLE )
 			{ /* do nothing */
@@ -149,15 +149,15 @@ void dump_associated_rules( file, ds )
 FILE *file;
 int ds;
 	{
-	register int i, j;
-	register int num_associated_rules = 0;
+	int i, j;
+	int num_associated_rules = 0;
 	int rule_set[MAX_ASSOC_RULES + 1];
 	int *dset = dss[ds];
 	int size = dfasiz[ds];
 
 	for ( i = 1; i <= size; ++i )
 		{
-		register int rule_num = rule_linenum[assoc_rule[dset[i]]];
+		int rule_num = rule_linenum[assoc_rule[dset[i]]];
 
 		for ( j = 1; j <= num_associated_rules; ++j )
 			if ( rule_num == rule_set[j] )
@@ -201,7 +201,7 @@ void dump_transitions( file, state )
 FILE *file;
 int state[];
 	{
-	register int i, ec;
+	int i, ec;
 	int out_char_set[CSIZE];
 
 	for ( i = 0; i < csize; ++i )
@@ -249,7 +249,7 @@ int state[];
 int *epsclosure( t, ns_addr, accset, nacc_addr, hv_addr )
 int *t, *ns_addr, accset[], *nacc_addr, *hv_addr;
 	{
-	register int stkpos, ns, tsp;
+	int stkpos, ns, tsp;
 	int numstates = *ns_addr, nacc, hashval, transsym, nfaccnum;
 	int stkend, nstate;
 	static int did_stk_init = false, *stk; 
@@ -681,7 +681,7 @@ void ntod()
 
 		if ( caseins && ! useecs )
 			{
-			register int j;
+			int j;
 
 			for ( i = 'A', j = 'a'; i <= 'Z'; ++i, ++j )
 				{
@@ -796,7 +796,7 @@ int snstods( sns, numstates, accset, nacc, hashval, newds_addr )
 int sns[], numstates, accset[], nacc, hashval, *newds_addr;
 	{
 	int didsort = 0;
-	register int i, j;
+	int i, j;
 	int newds, *oldsns;
 
 	for ( i = 1; i <= lastdfa; ++i )
diff --git a/usr.bin/lex/ecs.c b/usr.bin/lex/ecs.c
index d647142f4054..4f7748d8f1d6 100644
--- a/usr.bin/lex/ecs.c
+++ b/usr.bin/lex/ecs.c
@@ -144,7 +144,7 @@ int lenccl, fwd[], bck[], llsiz, NUL_mapping;
 			{ /* look for the symbol in the character class */
 			for ( ; j < lenccl; ++j )
 				{
-				register int ccl_char;
+				int ccl_char;
 
 				if ( NUL_mapping && ccls[j] == 0 )
 					ccl_char = NUL_mapping;
diff --git a/usr.bin/lex/gen.c b/usr.bin/lex/gen.c
index 7ccf4da84a80..b72688b63747 100644
--- a/usr.bin/lex/gen.c
+++ b/usr.bin/lex/gen.c
@@ -63,7 +63,7 @@ static char C_state_decl[] =
 
 void do_indent()
 	{
-	register int i = indent_level * 8;
+	int i = indent_level * 8;
 
 	while ( i >= 8 )
 		{
@@ -133,7 +133,7 @@ void gen_bu_action()
 
 void genctbl()
 	{
-	register int i;
+	int i;
 	int end_of_buffer_action = num_rules + 1;
 
 	/* Table of verify for transition and offset to next state. */
@@ -229,7 +229,7 @@ void genctbl()
 
 void genecs()
 	{
-	register int i, j;
+	int i, j;
 	int numrows;
 
 	out_str_dec( C_int_decl, "yy_ec", csize );
@@ -412,7 +412,7 @@ void gen_find_action()
 
 void genftbl()
 	{
-	register int i;
+	int i;
 	int end_of_buffer_action = num_rules + 1;
 
 	out_str_dec( long_align ? C_long_decl : C_short_decl,
@@ -422,7 +422,7 @@ void genftbl()
 
 	for ( i = 1; i <= lastdfa; ++i )
 		{
-		register int anum = dfaacc[i].dfaacc_state;
+		int anum = dfaacc[i].dfaacc_state;
 
 		mkdata( anum );
 
@@ -447,7 +447,7 @@ void genftbl()
 void gen_next_compressed_state( char_map )
 char *char_map;
 	{
-	indent_put2s( "register YY_CHAR yy_c = %s;", char_map );
+	indent_put2s( "YY_CHAR yy_c = %s;", char_map );
 
 	/* Save the backing-up info \before/ computing the next state
 	 * because we always compute one more state than needed - we
@@ -534,8 +534,8 @@ void gen_next_match()
 		{
 		indent_puts( "{" );	/* } for vi */
 		indent_puts(
-		"register yyconst struct yy_trans_info *yy_trans_info;\n" );
-		indent_puts( "register YY_CHAR yy_c;\n" );
+		"yyconst struct yy_trans_info *yy_trans_info;\n" );
+		indent_puts( "YY_CHAR yy_c;\n" );
 		indent_put2s( "for ( yy_c = %s;", char_map );
 		indent_puts(
 	"      (yy_trans_info = &yy_current_state[(unsigned int) yy_c])->" );
@@ -676,7 +676,7 @@ void gen_NUL_trans()
 		/* We're going to need yy_cp lying around for the call
 		 * below to gen_backing_up().
 		 */
-		indent_puts( "register char *yy_cp = yy_c_buf_p;" );
+		indent_puts( "char *yy_cp = yy_c_buf_p;" );
 
 	outc( '\n' );
 
@@ -698,10 +698,10 @@ void gen_NUL_trans()
 	else if ( fullspd )
 		{
 		do_indent();
-		out_dec( "register int yy_c = %d;\n", NUL_ec );
+		out_dec( "int yy_c = %d;\n", NUL_ec );
 
 		indent_puts(
-		"register yyconst struct yy_trans_info *yy_trans_info;\n" );
+		"yyconst struct yy_trans_info *yy_trans_info;\n" );
 		indent_puts(
 		"yy_trans_info = &yy_current_state[(unsigned int) yy_c];" );
 		indent_puts( "yy_current_state += yy_trans_info->yy_nxt;" );
@@ -959,7 +959,7 @@ void gentabs()
 
 	for ( i = 1; i <= lastdfa; ++i )
 		{
-		register int d = def[i];
+		int d = def[i];
 
 		if ( base[i] == JAMSTATE )
 			base[i] = jambase;
@@ -1060,7 +1060,7 @@ char str[];
 
 void make_tables()
 	{
-	register int i;
+	int i;
 	int did_eof_rule = false;
 
 	skelout();
diff --git a/usr.bin/lex/initscan.c b/usr.bin/lex/initscan.c
index a7316ba92037..7617c693dd40 100644
--- a/usr.bin/lex/initscan.c
+++ b/usr.bin/lex/initscan.c
@@ -1486,9 +1486,9 @@ YY_MALLOC_DECL
 
 YY_DECL
 	{
-	register yy_state_type yy_current_state;
-	register char *yy_cp, *yy_bp;
-	register int yy_act;
+	yy_state_type yy_current_state;
+	char *yy_cp, *yy_bp;
+	int yy_act;
 
 #line 94 "scan.l"
 
@@ -1544,7 +1544,7 @@ YY_DECL
 yy_match:
 		do
 			{
-			register YY_CHAR yy_c = yy_ec[YY_SC_TO_UI(*yy_cp)];
+			YY_CHAR yy_c = yy_ec[YY_SC_TO_UI(*yy_cp)];
 			if ( yy_accept[yy_current_state] )
 				{
 				yy_last_accepting_state = yy_current_state;
@@ -2297,7 +2297,7 @@ case 106:
 YY_RULE_SETUP
 #line 435 "scan.l"
 {
-			register Char *nmdefptr;
+			Char *nmdefptr;
 			Char *ndlookup();
 
 			strcpy( nmstr, yytext + 1 );
@@ -2896,9 +2896,9 @@ case YY_STATE_EOF(LINEDIR):
 
 static int yy_get_next_buffer()
 	{
-	register char *dest = yy_current_buffer->yy_ch_buf;
-	register char *source = yytext_ptr;
-	register int number_to_move, i;
+	char *dest = yy_current_buffer->yy_ch_buf;
+	char *source = yytext_ptr;
+	int number_to_move, i;
 	int ret_val;
 
 	if ( yy_c_buf_p > &yy_current_buffer->yy_ch_buf[yy_n_chars + 1] )
@@ -3028,15 +3028,15 @@ static int yy_get_next_buffer()
 
 static yy_state_type yy_get_previous_state()
 	{
-	register yy_state_type yy_current_state;
-	register char *yy_cp;
+	yy_state_type yy_current_state;
+	char *yy_cp;
 
 	yy_current_state = yy_start;
 	yy_current_state += YY_AT_BOL();
 
 	for ( yy_cp = yytext_ptr + YY_MORE_ADJ; yy_cp < yy_c_buf_p; ++yy_cp )
 		{
-		register YY_CHAR yy_c = (*yy_cp ? yy_ec[YY_SC_TO_UI(*yy_cp)] : 1);
+		YY_CHAR yy_c = (*yy_cp ? yy_ec[YY_SC_TO_UI(*yy_cp)] : 1);
 		if ( yy_accept[yy_current_state] )
 			{
 			yy_last_accepting_state = yy_current_state;
@@ -3068,10 +3068,10 @@ static yy_state_type yy_try_NUL_trans( yy_current_state )
 yy_state_type yy_current_state;
 #endif
 	{
-	register int yy_is_jam;
-	register char *yy_cp = yy_c_buf_p;
+	int yy_is_jam;
+	char *yy_cp = yy_c_buf_p;
 
-	register YY_CHAR yy_c = 1;
+	YY_CHAR yy_c = 1;
 	if ( yy_accept[yy_current_state] )
 		{
 		yy_last_accepting_state = yy_current_state;
@@ -3092,14 +3092,14 @@ yy_state_type yy_current_state;
 
 #ifndef YY_NO_UNPUT
 #ifdef YY_USE_PROTOS
-static void yyunput( int c, register char *yy_bp )
+static void yyunput( int c, char *yy_bp )
 #else
 static void yyunput( c, yy_bp )
 int c;
-register char *yy_bp;
+char *yy_bp;
 #endif
 	{
-	register char *yy_cp = yy_c_buf_p;
+	char *yy_cp = yy_c_buf_p;
 
 	/* undo effects of setting up yytext */
 	*yy_cp = yy_hold_char;
@@ -3107,10 +3107,10 @@ register char *yy_bp;
 	if ( yy_cp < yy_current_buffer->yy_ch_buf + 2 )
 		{ /* need to shift things up to make room */
 		/* +2 for EOB chars. */
-		register int number_to_move = yy_n_chars + 2;
-		register char *dest = &yy_current_buffer->yy_ch_buf[
+		int number_to_move = yy_n_chars + 2;
+		char *dest = &yy_current_buffer->yy_ch_buf[
 					yy_current_buffer->yy_buf_size + 2];
-		register char *source =
+		char *source =
 				&yy_current_buffer->yy_ch_buf[number_to_move];
 
 		while ( source > yy_current_buffer->yy_ch_buf )
@@ -3572,7 +3572,7 @@ yyconst char *s2;
 int n;
 #endif
 	{
-	register int i;
+	int i;
 	for ( i = 0; i < n; ++i )
 		s1[i] = s2[i];
 	}
@@ -3586,7 +3586,7 @@ static int yy_flex_strlen( s )
 yyconst char *s;
 #endif
 	{
-	register int n;
+	int n;
 	for ( n = 0; s[n]; ++n )
 		;
 
diff --git a/usr.bin/lex/misc.c b/usr.bin/lex/misc.c
index 3eda5793650c..6048f5de9de0 100644
--- a/usr.bin/lex/misc.c
+++ b/usr.bin/lex/misc.c
@@ -84,7 +84,7 @@ void *allocate_array( size, element_size )
 int size;
 size_t element_size;
 	{
-	register void *mem;
+	void *mem;
 	size_t num_bytes = element_size * size;
 
 	mem = flex_alloc( num_bytes );
@@ -99,7 +99,7 @@ size_t element_size;
 /* all_lower - true if a string is all lower-case */
 
 int all_lower( str )
-register char *str;
+char *str;
 	{
 	while ( *str )
 		{
@@ -115,7 +115,7 @@ register char *str;
 /* all_upper - true if a string is all upper-case */
 
 int all_upper( str )
-register char *str;
+char *str;
 	{
 	while ( *str )
 		{
@@ -146,7 +146,7 @@ register char *str;
 void bubble( v, n )
 int v[], n;
 	{
-	register int i, j, k;
+	int i, j, k;
 
 	for ( i = n; i > 1; --i )
 		for ( j = 1; j < i; ++j )
@@ -182,7 +182,7 @@ int c;
 /* clower - replace upper-case letter to lower-case */
 
 Char clower( c )
-register int c;
+int c;
 	{
 	return (Char) ((isascii( c ) && isupper( c )) ? tolower( c ) : c);
 	}
@@ -191,10 +191,10 @@ register int c;
 /* copy_string - returns a dynamically allocated copy of a string */
 
 char *copy_string( str )
-register const char *str;
+const char *str;
 	{
-	register const char *c1;
-	register char *c2;
+	const char *c1;
+	char *c2;
 	char *copy;
 	unsigned int size;
 
@@ -220,9 +220,9 @@ register const char *str;
  */
 
 Char *copy_unsigned_string( str )
-register Char *str;
+Char *str;
 	{
-	register Char *c;
+	Char *c;
 	Char *copy;
 
 	/* find length */
@@ -655,7 +655,7 @@ unsigned int x;
 void out_line_count( str )
 const char str[];
 	{
-	register int i;
+	int i;
 
 	for ( i = 0; str[i]; ++i )
 		if ( str[i] == '\n' )
@@ -713,7 +713,7 @@ const char str[];
  */
 
 char *readable_form( c )
-register int c;
+int c;
 	{
 	static char rform[10];
 
@@ -759,7 +759,7 @@ void *array;
 int size;
 size_t element_size;
 	{
-	register void *new_array;
+	void *new_array;
 	size_t num_bytes = element_size * size;
 
 	new_array = flex_realloc( array, num_bytes );
@@ -878,7 +878,7 @@ void zero_out( region_ptr, size_in_bytes )
 char *region_ptr;
 size_t size_in_bytes;
 	{
-	register char *rp, *rp_end;
+	char *rp, *rp_end;
 
 	rp = region_ptr;
 	rp_end = region_ptr + size_in_bytes;
diff --git a/usr.bin/lex/nfa.c b/usr.bin/lex/nfa.c
index 4b81284ff2ec..99b4ecffab50 100644
--- a/usr.bin/lex/nfa.c
+++ b/usr.bin/lex/nfa.c
@@ -321,7 +321,7 @@ int first, last;
  */
 
 void mark_beginning_as_normal( mach )
-register int mach;
+int mach;
 	{
 	switch ( state_type[mach] )
 		{
diff --git a/usr.bin/lex/sym.c b/usr.bin/lex/sym.c
index 077015b78578..2f43b50b8711 100644
--- a/usr.bin/lex/sym.c
+++ b/usr.bin/lex/sym.c
@@ -35,7 +35,7 @@ __FBSDID("$FreeBSD$");
 
 /* declare functions that have forward references */
 
-int hashfunct PROTO((register char[], int));
+int hashfunct PROTO((char[], int));
 
 
 struct hash_entry *ndtbl[NAME_TABLE_HASH_SIZE];
@@ -51,16 +51,16 @@ struct hash_entry *findsym();
  */
 
 int addsym( sym, str_def, int_def, table, table_size )
-register char sym[];
+char sym[];
 char *str_def;
 int int_def;
 hash_table table;
 int table_size;
 	{
 	int hash_val = hashfunct( sym, table_size );
-	register struct hash_entry *sym_entry = table[hash_val];
-	register struct hash_entry *new_entry;
-	register struct hash_entry *successor;
+	struct hash_entry *sym_entry = table[hash_val];
+	struct hash_entry *new_entry;
+	struct hash_entry *successor;
 
 	while ( sym_entry )
 		{
@@ -130,7 +130,7 @@ Char ccltxt[];
 /* findsym - find symbol in symbol table */
 
 struct hash_entry *findsym( sym, table, table_size )
-register char sym[];
+char sym[];
 hash_table table;
 int table_size;
 	{
@@ -139,7 +139,7 @@ int table_size;
 		(struct hash_entry *) 0, (struct hash_entry *) 0,
 		(char *) 0, (char *) 0, 0,
 		} ;
-	register struct hash_entry *sym_entry =
+	struct hash_entry *sym_entry =
 		table[hashfunct( sym, table_size )];
 
 	while ( sym_entry )
@@ -156,11 +156,11 @@ int table_size;
 /* hashfunct - compute the hash value for "str" and hash size "hash_size" */
 
 int hashfunct( str, hash_size )
-register char str[];
+char str[];
 int hash_size;
 	{
-	register int hashval;
-	register int locstr;
+	int hashval;
+	int locstr;
 
 	hashval = 0;
 	locstr = 0;
diff --git a/usr.bin/lex/tblcmp.c b/usr.bin/lex/tblcmp.c
index 89973f08ba87..12af3dc64fd7 100644
--- a/usr.bin/lex/tblcmp.c
+++ b/usr.bin/lex/tblcmp.c
@@ -35,7 +35,7 @@ __FBSDID("$FreeBSD$");
 
 /* declarations for functions that have forward references */
 
-void mkentry PROTO((register int*, int, int, int, int));
+void mkentry PROTO((int*, int, int, int, int));
 void mkprot PROTO((int[], int, int));
 void mktemplate PROTO((int[], int, int));
 void mv2front PROTO((int));
@@ -230,7 +230,7 @@ int state[], statenum, totaltrans, comstate, comfreq;
 void cmptmps()
 	{
 	int tmpstorage[CSIZE + 1];
-	register int *tmp = tmpstorage, i, j;
+	int *tmp = tmpstorage, i, j;
 	int totaltrans, trans;
 
 	peakpairs = numtemps * numecs + tblend;
@@ -302,7 +302,7 @@ void cmptmps()
 
 void expand_nxt_chk()
 	{
-	register int old_max = current_max_xpairs;
+	int old_max = current_max_xpairs;
 
 	current_max_xpairs += MAX_XPAIRS_INCREMENT;
 
@@ -341,9 +341,9 @@ int *state, numtrans;
 	/* Firstfree is the position of the first possible occurrence of two
 	 * consecutive unused records in the chk and nxt arrays.
 	 */
-	register int i;
-	register int *state_ptr, *chk_ptr;
-	register int *ptr_to_last_entry_in_state;
+	int i;
+	int *state_ptr, *chk_ptr;
+	int *ptr_to_last_entry_in_state;
 
 	/* If there are too many out-transitions, put the state at the end of
 	 * nxt and chk.
@@ -436,7 +436,7 @@ int *state, numtrans;
  */
 void inittbl()
 	{
-	register int i;
+	int i;
 
 	zero_out( (char *) chk, (size_t) (current_max_xpairs * sizeof( int )) );
 
@@ -517,10 +517,10 @@ void mkdeftbl()
  */
 
 void mkentry( state, numchars, statenum, deflink, totaltrans )
-register int *state;
+int *state;
 int numchars, statenum, deflink, totaltrans;
 	{
-	register int minec, maxec, i, baseaddr;
+	int minec, maxec, i, baseaddr;
 	int tblbase, tbllast;
 
 	if ( totaltrans == 0 )
@@ -794,8 +794,8 @@ int qelm;
 void place_state( state, statenum, transnum )
 int *state, statenum, transnum;
 	{
-	register int i;
-	register int *state_ptr;
+	int i;
+	int *state_ptr;
 	int position = find_table_space( state, transnum );
 
 	/* "base" is the table of start positions. */
@@ -869,8 +869,8 @@ int statenum, sym, nextstate, deflink;
 int tbldiff( state, pr, ext )
 int state[], pr, ext[];
 	{
-	register int i, *sp = state, *ep = ext, *protp;
-	register int numdiff = 0;
+	int i, *sp = state, *ep = ext, *protp;
+	int numdiff = 0;
 
 	protp = &protsave[numecs * (pr - 1)];