diff --git a/usr.bin/yacc/Makefile b/usr.bin/yacc/Makefile
index e8b1024e82bb..b55ca75d5b1d 100644
--- a/usr.bin/yacc/Makefile
+++ b/usr.bin/yacc/Makefile
@@ -4,6 +4,8 @@
 PROG=	yacc
 SRCS=	closure.c error.c lalr.c lr0.c main.c mkpar.c output.c reader.c \
 	skeleton.c symtab.c verbose.c warshall.c
+WARNS?=	2
+NO_WERROR=true # XXXX Temporary
 SCRIPTS=yyfix.sh
 MAN=	yacc.1 yyfix.1
 LINKS=	${BINDIR}/yacc ${BINDIR}/byacc
diff --git a/usr.bin/yacc/closure.c b/usr.bin/yacc/closure.c
index 4caf45857640..ed716a8314d1 100644
--- a/usr.bin/yacc/closure.c
+++ b/usr.bin/yacc/closure.c
@@ -61,12 +61,12 @@ static unsigned *EFF;
 static void
 set_EFF()
 {
-    register unsigned *row;
-    register int symbol;
-    register short *sp;
-    register int rowsize;
-    register int i;
-    register int rule;
+    unsigned *row;
+    int symbol;
+    short *sp;
+    int rowsize;
+    int i;
+    int rule;
 
     rowsize = WORDSIZE(nvars);
     EFF = NEW2(nvars * rowsize, unsigned);
@@ -98,12 +98,12 @@ set_EFF()
 void
 set_first_derives()
 {
-    register unsigned *rrow;
-    register unsigned *vrow;
-    register int j;
-    register unsigned k;
-    register unsigned cword = 0;
-    register short *rp;
+    unsigned *rrow;
+    unsigned *vrow;
+    int j;
+    unsigned k;
+    unsigned cword = 0;
+    short *rp;
 
     int rule;
     int i;
@@ -156,13 +156,13 @@ closure(nucleus, n)
 short *nucleus;
 int n;
 {
-    register int ruleno;
-    register unsigned word;
-    register unsigned i;
-    register short *csp;
-    register unsigned *dsp;
-    register unsigned *rsp;
-    register int rulesetsize;
+    int ruleno;
+    unsigned word;
+    unsigned i;
+    short *csp;
+    unsigned *dsp;
+    unsigned *rsp;
+    int rulesetsize;
 
     short *csend;
     unsigned *rsend;
@@ -237,7 +237,7 @@ static void
 print_closure(n)
 int n;
 {
-  register short *isp;
+  short *isp;
 
   printf("\n\nn = %d\n\n", n);
   for (isp = itemset; isp < itemsetend; isp++)
@@ -248,10 +248,10 @@ int n;
 static void
 print_EFF()
 {
-    register int i, j;
-    register unsigned *rowp;
-    register unsigned word;
-    register unsigned k;
+    int i, j;
+    unsigned *rowp;
+    unsigned word;
+    unsigned k;
 
     printf("\n\nEpsilon Free Firsts\n");
 
@@ -280,11 +280,11 @@ print_EFF()
 static void
 print_first_derives()
 {
-    register int i;
-    register int j;
-    register unsigned *rp;
-    register unsigned cword;
-    register unsigned k;
+    int i;
+    int j;
+    unsigned *rp;
+    unsigned cword;
+    unsigned k;
 
     printf("\n\n\nFirst Derives\n");
 
diff --git a/usr.bin/yacc/defs.h b/usr.bin/yacc/defs.h
index 43af00b191a6..f2a8f87ac463 100644
--- a/usr.bin/yacc/defs.h
+++ b/usr.bin/yacc/defs.h
@@ -225,7 +225,7 @@ extern char lflag;
 extern char rflag;
 extern char tflag;
 extern char vflag;
-extern char *symbol_prefix;
+extern const char *symbol_prefix;
 
 extern char *myname;
 extern char *cptr;
@@ -233,16 +233,16 @@ extern char *line;
 extern int lineno;
 extern int outline;
 
-extern char *banner[];
-extern char *tables[];
-extern char *header[];
-extern char *body[];
-extern char *trailer[];
+extern const char *banner[];
+extern const char *tables[];
+extern const char *header[];
+extern const char *body[];
+extern const char *trailer[];
 
 extern char *action_file_name;
 extern char *code_file_name;
 extern char *defines_file_name;
-extern char *input_file_name;
+extern const char *input_file_name;
 extern char *output_file_name;
 extern char *text_file_name;
 extern char *union_file_name;
@@ -319,7 +319,7 @@ void default_action_warning __P((void));
 void dollar_error __P((int, char *, char *));
 void dollar_warning __P((int, int));
 void done __P((int));
-void fatal __P((char *msg));
+void fatal __P((const char *msg));
 void finalize_closure __P((void));
 void free_parser __P((void));
 void free_symbols __P((void));
@@ -329,11 +329,11 @@ void illegal_tag __P((int, char *, char *));
 void lalr __P((void));
 bucket *lookup __P((char *));
 void lr0 __P((void));
-bucket *make_bucket __P((char *));
+bucket *make_bucket __P((const char *));
 void make_parser __P((void));
 void no_grammar __P((void));
 void no_space __P((void));
-void open_error __P((char *));
+void open_error __P((const char *));
 void output __P((void));
 void over_unionized __P((char *));
 void prec_redeclared __P((void));
@@ -361,4 +361,4 @@ void untyped_lhs __P((void));
 void untyped_rhs __P((int, char *));
 void used_reserved __P((char *));
 void verbose __P((void));
-void write_section __P((char **));
+void write_section __P((const char **));
diff --git a/usr.bin/yacc/error.c b/usr.bin/yacc/error.c
index 3229f345104c..60a22bf4aa14 100644
--- a/usr.bin/yacc/error.c
+++ b/usr.bin/yacc/error.c
@@ -50,7 +50,7 @@ static void print_pos __P((char *, char *));
 
 void
 fatal(msg)
-char *msg;
+const char *msg;
 {
     warnx("f - %s", msg);
     done(2);
@@ -67,7 +67,7 @@ no_space()
 
 void
 open_error(filename)
-char *filename;
+const char *filename;
 {
     warnx("f - cannot open \"%s\"", filename);
     done(2);
@@ -88,7 +88,7 @@ print_pos(st_line, st_cptr)
 char *st_line;
 char *st_cptr;
 {
-    register char *s;
+    char *s;
 
     if (st_line == 0) return;
     for (s = st_line; *s != '\n'; ++s)
diff --git a/usr.bin/yacc/lalr.c b/usr.bin/yacc/lalr.c
index bd61e489e46b..d2654229f53e 100644
--- a/usr.bin/yacc/lalr.c
+++ b/usr.bin/yacc/lalr.c
@@ -78,7 +78,7 @@ static void set_reduction_table __P((void));
 static void set_shift_table __P((void));
 static void set_state_table __P((void));
 static short **transpose __P((short **, int));
-static void traverse __P((register int));
+static void traverse __P((int));
 
 static int infinity;
 static int maxrhs;
@@ -115,7 +115,7 @@ lalr()
 static void
 set_state_table()
 {
-    register core *sp;
+    core *sp;
 
     state_table = NEW2(nstates, core *);
     for (sp = first_state; sp; sp = sp->next)
@@ -127,7 +127,7 @@ set_state_table()
 static void
 set_accessing_symbol()
 {
-    register core *sp;
+    core *sp;
 
     accessing_symbol = NEW2(nstates, short);
     for (sp = first_state; sp; sp = sp->next)
@@ -139,7 +139,7 @@ set_accessing_symbol()
 static void
 set_shift_table()
 {
-    register shifts *sp;
+    shifts *sp;
 
     shift_table = NEW2(nstates, shifts *);
     for (sp = first_shift; sp; sp = sp->next)
@@ -151,7 +151,7 @@ set_shift_table()
 static void
 set_reduction_table()
 {
-    register reductions *rp;
+    reductions *rp;
 
     reduction_table = NEW2(nstates, reductions *);
     for (rp = first_reduction; rp; rp = rp->next)
@@ -163,10 +163,10 @@ set_reduction_table()
 static void
 set_maxrhs()
 {
-  register short *itemp;
-  register short *item_end;
-  register int length;
-  register int max;
+  short *itemp;
+  short *item_end;
+  int length;
+  int max;
 
   length = 0;
   max = 0;
@@ -192,8 +192,8 @@ set_maxrhs()
 static void
 initialize_LA()
 {
-  register int i, j, k;
-  register reductions *rp;
+  int i, j, k;
+  reductions *rp;
 
   lookaheads = NEW2(nstates + 1, short);
 
@@ -230,13 +230,13 @@ initialize_LA()
 static void
 set_goto_map()
 {
-  register shifts *sp;
-  register int i;
-  register int symbol;
-  register int k;
-  register short *temp_map;
-  register int state2;
-  register int state1;
+  shifts *sp;
+  int i;
+  int symbol;
+  int k;
+  short *temp_map;
+  int state2;
+  int state1;
 
   goto_map = NEW2(nvars + 1, short) - ntokens;
   temp_map = NEW2(nvars + 1, short) - ntokens;
@@ -302,10 +302,10 @@ map_goto(state, symbol)
 int state;
 int symbol;
 {
-    register int high;
-    register int low;
-    register int middle;
-    register int s;
+    int high;
+    int low;
+    int middle;
+    int s;
 
     low = goto_map[symbol];
     high = goto_map[symbol + 1];
@@ -329,18 +329,18 @@ int symbol;
 static void
 initialize_F()
 {
-  register int i;
-  register int j;
-  register int k;
-  register shifts *sp;
-  register short *edge;
-  register unsigned *rowp;
-  register short *rp;
-  register short **reads;
-  register int nedges;
-  register int stateno;
-  register int symbol;
-  register int nwords;
+  int i;
+  int j;
+  int k;
+  shifts *sp;
+  short *edge;
+  unsigned *rowp;
+  short *rp;
+  short **reads;
+  int nedges;
+  int stateno;
+  int symbol;
+  int nwords;
 
   nwords = ngotos * tokensetsize;
   F = NEW2(nwords, unsigned);
@@ -407,23 +407,23 @@ initialize_F()
 static void
 build_relations()
 {
-  register int i;
-  register int j;
-  register int k;
-  register short *rulep;
-  register short *rp;
-  register shifts *sp;
-  register int length;
-  register int nedges;
-  register int done;
-  register int state1;
-  register int stateno;
-  register int symbol1;
-  register int symbol2;
-  register short *shortp;
-  register short *edge;
-  register short *states;
-  register short **new_includes;
+  int i;
+  int j;
+  int k;
+  short *rulep;
+  short *rp;
+  shifts *sp;
+  int length;
+  int nedges;
+  int done1;
+  int state1;
+  int stateno;
+  int symbol1;
+  int symbol2;
+  short *shortp;
+  short *edge;
+  short *states;
+  short **new_includes;
 
   includes = NEW2(ngotos, short *);
   edge = NEW2(ngotos + 1, short);
@@ -459,16 +459,16 @@ build_relations()
 	  add_lookback_edge(stateno, *rulep, i);
 
 	  length--;
-	  done = 0;
-	  while (!done)
+	  done1 = 0;
+	  while (!done1)
 	    {
-	      done = 1;
+	      done1 = 1;
 	      rp--;
 	      if (ISVAR(*rp))
 		{
 		  stateno = states[--length];
 		  edge[nedges++] = map_goto(stateno, *rp);
-		  if (nullable[*rp] && length > 0) done = 0;
+		  if (nullable[*rp] && length > 0) done1 = 0;
 		}
 	    }
 	}
@@ -501,9 +501,9 @@ static void
 add_lookback_edge(stateno, ruleno, gotono)
 int stateno, ruleno, gotono;
 {
-    register int i, k;
-    register int found;
-    register shorts *sp;
+    int i, k;
+    int found;
+    shorts *sp;
 
     i = lookaheads[stateno];
     k = lookaheads[stateno + 1];
@@ -526,22 +526,22 @@ int stateno, ruleno, gotono;
 
 
 static short **
-transpose(R, n)
-short **R;
+transpose(r, n)
+short **r;
 int n;
 {
-  register short **new_R;
-  register short **temp_R;
-  register short *nedges;
-  register short *sp;
-  register int i;
-  register int k;
+  short **new_r;
+  short **temp_r;
+  short *nedges;
+  short *sp;
+  int i;
+  int k;
 
   nedges = NEW2(n, short);
 
   for (i = 0; i < n; i++)
     {
-      sp = R[i];
+      sp = r[i];
       if (sp)
 	{
 	  while (*sp >= 0)
@@ -549,8 +549,8 @@ int n;
 	}
     }
 
-  new_R = NEW2(n, short *);
-  temp_R = NEW2(n, short *);
+  new_r = NEW2(n, short *);
+  temp_r = NEW2(n, short *);
 
   for (i = 0; i < n; i++)
     {
@@ -558,8 +558,8 @@ int n;
       if (k > 0)
 	{
 	  sp = NEW2(k + 1, short);
-	  new_R[i] = sp;
-	  temp_R[i] = sp;
+	  new_r[i] = sp;
+	  temp_r[i] = sp;
 	  sp[k] = -1;
 	}
     }
@@ -568,17 +568,17 @@ int n;
 
   for (i = 0; i < n; i++)
     {
-      sp = R[i];
+      sp = r[i];
       if (sp)
 	{
 	  while (*sp >= 0)
-	    *temp_R[*sp++]++ = i;
+	    *temp_r[*sp++]++ = i;
 	}
     }
 
-  FREE(temp_R);
+  FREE(temp_r);
 
-  return (new_R);
+  return (new_r);
 }
 
 
@@ -593,10 +593,10 @@ compute_FOLLOWS()
 static void
 compute_lookaheads()
 {
-  register int i, n;
-  register unsigned *fp1, *fp2, *fp3;
-  register shorts *sp, *next;
-  register unsigned *rowp;
+  int i, n;
+  unsigned *fp1, *fp2, *fp3;
+  shorts *sp, *next;
+  unsigned *rowp;
 
   rowp = LA;
   n = lookaheads[nstates];
@@ -629,7 +629,7 @@ static void
 digraph(relation)
 short **relation;
 {
-  register int i;
+  int i;
 
   infinity = ngotos + 2;
   INDEX = NEW2(ngotos + 1, short);
@@ -655,13 +655,13 @@ short **relation;
 
 static void
 traverse(i)
-register int i;
+int i;
 {
-  register unsigned *fp1;
-  register unsigned *fp2;
-  register unsigned *fp3;
-  register int j;
-  register short *rp;
+  unsigned *fp1;
+  unsigned *fp2;
+  unsigned *fp3;
+  int j;
+  short *rp;
 
   int height;
   unsigned *base;
diff --git a/usr.bin/yacc/lr0.c b/usr.bin/yacc/lr0.c
index 07816d2ac114..3280c5634660 100644
--- a/usr.bin/yacc/lr0.c
+++ b/usr.bin/yacc/lr0.c
@@ -89,13 +89,13 @@ static short *kernel_items;
 static void
 allocate_itemsets()
 {
-    register short *itemp;
-    register short *item_end;
-    register int symbol;
-    register int i;
-    register int count;
-    register int max;
-    register short *symbol_count;
+    short *itemp;
+    short *item_end;
+    int symbol;
+    int i;
+    int count;
+    int max;
+    short *symbol_count;
 
     count = 0;
     symbol_count = NEW2(nsyms, short);
@@ -142,9 +142,9 @@ allocate_storage()
 static void
 append_states()
 {
-    register int i;
-    register int j;
-    register int symbol;
+    int i;
+    int j;
+    int symbol;
 
 #ifdef	TRACE
     fprintf(stderr, "Entering append_states()\n");
@@ -215,13 +215,13 @@ static int
 get_state(symbol)
 int symbol;
 {
-    register int key;
-    register short *isp1;
-    register short *isp2;
-    register short *iend;
-    register core *sp;
-    register int found;
-    register int n;
+    int key;
+    short *isp1;
+    short *isp2;
+    short *iend;
+    core *sp;
+    int found;
+    int n;
 
 #ifdef	TRACE
     fprintf(stderr, "Entering get_state(%d)\n", symbol);
@@ -279,9 +279,9 @@ int symbol;
 static void
 initialize_states()
 {
-    register int i;
-    register short *start_derives;
-    register core *p;
+    int i;
+    short *start_derives;
+    core *p;
 
     start_derives = derives[start_symbol];
     for (i = 0; start_derives[i] >= 0; ++i)
@@ -307,11 +307,11 @@ initialize_states()
 static void
 new_itemsets()
 {
-    register int i;
-    register int shiftcount;
-    register short *isp;
-    register short *ksp;
-    register int symbol;
+    int i;
+    int shiftcount;
+    short *isp;
+    short *ksp;
+    int symbol;
 
     for (i = 0; i < nsyms; i++)
 	kernel_end[i] = 0;
@@ -345,11 +345,11 @@ static core *
 new_state(symbol)
 int symbol;
 {
-    register int n;
-    register core *p;
-    register short *isp1;
-    register short *isp2;
-    register short *iend;
+    int n;
+    core *p;
+    short *isp1;
+    short *isp2;
+    short *iend;
 
 #ifdef	TRACE
     fprintf(stderr, "Entering new_state(%d)\n", symbol);
@@ -461,10 +461,10 @@ show_shifts()
 static void
 save_shifts()
 {
-    register shifts *p;
-    register short *sp1;
-    register short *sp2;
-    register short *send;
+    shifts *p;
+    short *sp1;
+    short *sp2;
+    short *send;
 
     p = (shifts *) allocate((unsigned) (sizeof(shifts) +
 			(nshifts - 1) * sizeof(short)));
@@ -496,13 +496,13 @@ save_shifts()
 static void
 save_reductions()
 {
-    register short *isp;
-    register short *rp1;
-    register short *rp2;
-    register int item;
-    register int count;
-    register reductions *p;
-    register short *rend;
+    short *isp;
+    short *rp1;
+    short *rp2;
+    int item;
+    int count;
+    reductions *p;
+    short *rend;
 
     count = 0;
     for (isp = itemset; isp < itemsetend; isp++)
@@ -546,9 +546,9 @@ save_reductions()
 static void
 set_derives()
 {
-    register int i, k;
-    register int lhs;
-    register short *rules;
+    int i, k;
+    int lhs;
+    short *rules;
 
     derives = NEW2(nsyms, short *);
     rules = NEW2(nvars + nrules, short);
@@ -586,8 +586,8 @@ free_derives()
 static void
 print_derives()
 {
-    register int i;
-    register short *sp;
+    int i;
+    short *sp;
 
     printf("\nDERIVES\n\n");
 
@@ -609,9 +609,9 @@ print_derives()
 static void
 set_nullable()
 {
-    register int i, j;
-    register int empty;
-    int done;
+    int i, j;
+    int empty;
+    int done1;
 
     nullable = MALLOC(nsyms);
     if (nullable == 0) no_space();
@@ -619,10 +619,10 @@ set_nullable()
     for (i = 0; i < nsyms; ++i)
 	nullable[i] = 0;
 
-    done = 0;
-    while (!done)
+    done1 = 0;
+    while (!done1)
     {
-	done = 1;
+	done1 = 1;
 	for (i = 1; i < nitems; i++)
 	{
 	    empty = 1;
@@ -638,7 +638,7 @@ set_nullable()
 		if (!nullable[j])
 		{
 		    nullable[j] = 1;
-		    done = 0;
+		    done1 = 0;
 		}
 	    }
 	}
diff --git a/usr.bin/yacc/main.c b/usr.bin/yacc/main.c
index f26a38b0f680..3cba3a2eb648 100644
--- a/usr.bin/yacc/main.c
+++ b/usr.bin/yacc/main.c
@@ -60,9 +60,9 @@ char rflag;
 char tflag;
 char vflag;
 
-char *symbol_prefix;
-char *file_prefix = "y";
-char *temp_form = "yacc.XXXXXXXXXXX";
+const char *symbol_prefix;
+const char *file_prefix = "y";
+char temp_form[] = "yacc.XXXXXXXXXXX";
 
 int lineno;
 int outline;
@@ -70,7 +70,7 @@ int outline;
 char *action_file_name;
 char *code_file_name;
 char *defines_file_name;
-char *input_file_name = "";
+const char *input_file_name = "";
 char *output_file_name;
 char *text_file_name;
 char *union_file_name;
@@ -130,7 +130,7 @@ int k;
 
 static void
 onintr(signo)
-	int signo;
+	int signo __unused;
 {
     done(1);
 }
@@ -169,8 +169,8 @@ getargs(argc, argv)
 int argc;
 char *argv[];
 {
-    register int i;
-    register char *s;
+    int i;
+    char *s;
 
     for (i = 1; i < argc; ++i)
     {
@@ -282,7 +282,7 @@ char *
 allocate(n)
 unsigned n;
 {
-    register char *p;
+    char *p;
 
     p = NULL;
     if (n)
@@ -298,7 +298,7 @@ static void
 create_file_names()
 {
     int i, len;
-    char *tmpdir;
+    const char *tmpdir;
 
     tmpdir = getenv("TMPDIR");
     if (tmpdir == 0) tmpdir = "/tmp";
diff --git a/usr.bin/yacc/mkpar.c b/usr.bin/yacc/mkpar.c
index e7ca1e36b91b..c4e3b0907a4c 100644
--- a/usr.bin/yacc/mkpar.c
+++ b/usr.bin/yacc/mkpar.c
@@ -75,7 +75,7 @@ static void unused_rules __P((void));
 void
 make_parser()
 {
-    register int i;
+    int i;
 
     parser = NEW2(nstates, action *);
     for (i = 0; i < nstates; i++)
@@ -91,9 +91,9 @@ make_parser()
 
 static action *
 parse_actions(stateno)
-register int stateno;
+int stateno;
 {
-    register action *actions;
+    action *actions;
 
     actions = get_shifts(stateno);
     actions = add_reductions(stateno, actions);
@@ -105,20 +105,20 @@ static action *
 get_shifts(stateno)
 int stateno;
 {
-    register action *actions, *temp;
-    register shifts *sp;
-    register short *to_state;
-    register int i, k;
-    register int symbol;
+    action *actions, *temp;
+    shifts *sp;
+    short *tostate;
+    int i, k;
+    int symbol;
 
     actions = 0;
     sp = shift_table[stateno];
     if (sp)
     {
-	to_state = sp->shift;
+	tostate = sp->shift;
 	for (i = sp->nshifts - 1; i >= 0; i--)
 	{
-	    k = to_state[i];
+	    k = tostate[i];
 	    symbol = accessing_symbol[k];
 	    if (ISTOKEN(symbol))
 	    {
@@ -139,11 +139,11 @@ int stateno;
 static action *
 add_reductions(stateno, actions)
 int stateno;
-register action *actions;
+action *actions;
 {
-    register int i, j, m, n;
-    register int ruleno, tokensetsize;
-    register unsigned *rowp;
+    int i, j, m, n;
+    int ruleno, tokensetsize;
+    unsigned *rowp;
 
     tokensetsize = WORDSIZE(ntokens);
     m = lookaheads[stateno];
@@ -164,10 +164,10 @@ register action *actions;
 
 static action *
 add_reduce(actions, ruleno, symbol)
-register action *actions;
-register int ruleno, symbol;
+action *actions;
+int ruleno, symbol;
 {
-    register action *temp, *prev, *next;
+    action *temp, *prev, *next;
 
     prev = 0;
     for (next = actions; next && next->symbol < symbol; next = next->next)
@@ -206,16 +206,16 @@ register int ruleno, symbol;
 static void
 find_final_state()
 {
-    register int goal, i;
-    register short *to_state;
-    register shifts *p;
+    int goal, i;
+    short *tostate;
+    shifts *p;
 
     p = shift_table[0];
-    to_state = p->shift;
+    tostate = p->shift;
     goal = ritem[1];
     for (i = p->nshifts - 1; i >= 0; --i)
     {
-	final_state = to_state[i];
+	final_state = tostate[i];
 	if (accessing_symbol[final_state] == goal) break;
     }
 }
@@ -224,8 +224,8 @@ find_final_state()
 static void
 unused_rules()
 {
-    register int i;
-    register action *p;
+    int i;
+    action *p;
 
     rules_used = (short *) MALLOC(nrules*sizeof(short));
     if (rules_used == 0) no_space();
@@ -258,9 +258,9 @@ unused_rules()
 static void
 remove_conflicts()
 {
-    register int i;
-    register int symbol;
-    register action *p, *pref = NULL;
+    int i;
+    int symbol;
+    action *p, *pref = NULL;
 
     SRtotal = 0;
     RRtotal = 0;
@@ -354,8 +354,8 @@ static int
 sole_reduction(stateno)
 int stateno;
 {
-    register int count, ruleno;
-    register action *p;
+    int count, ruleno;
+    action *p;
 
     count = 0;
     ruleno = 0;
@@ -382,7 +382,7 @@ int stateno;
 static void
 defreds()
 {
-    register int i;
+    int i;
 
     defred = NEW2(nstates, short);
     for (i = 0; i < nstates; i++)
@@ -391,9 +391,9 @@ defreds()
 
 static void
 free_action_row(p)
-register action *p;
+action *p;
 {
-  register action *q;
+  action *q;
 
   while (p)
     {
@@ -406,7 +406,7 @@ register action *p;
 void
 free_parser()
 {
-  register int i;
+  int i;
 
   for (i = 0; i < nstates; i++)
     free_action_row(parser[i]);
diff --git a/usr.bin/yacc/output.c b/usr.bin/yacc/output.c
index 49cae39d3b75..fed4a530f8cf 100644
--- a/usr.bin/yacc/output.c
+++ b/usr.bin/yacc/output.c
@@ -181,8 +181,8 @@ output_prefix()
 static void
 output_rule_data()
 {
-    register int i;
-    register int j;
+    int i;
+    int j;
 
 
     fprintf(output_file, "const short %slhs[] = {%42d,", symbol_prefix,
@@ -229,7 +229,7 @@ output_rule_data()
 static void
 output_yydefred()
 {
-    register int i, j;
+    int i, j;
 
     fprintf(output_file, "const short %sdefred[] = {%39d,", symbol_prefix,
 	    (defred[0] ? defred[0] - 2 : 0));
@@ -286,11 +286,11 @@ output_actions()
 static void
 token_actions()
 {
-    register int i, j;
-    register int shiftcount, reducecount;
-    register int max, min;
-    register short *actionrow, *r, *s;
-    register action *p;
+    int i, j;
+    int shiftcount, reducecount;
+    int max, min;
+    short *actionrow, *r, *s;
+    action *p;
 
     actionrow = NEW2(2*ntokens, short);
     for (i = 0; i < nstates; ++i)
@@ -371,7 +371,7 @@ token_actions()
 static void
 goto_actions()
 {
-    register int i, j, k;
+    int i, j, k;
 
     state_count = NEW2(nstates, short);
 
@@ -405,11 +405,11 @@ static int
 default_goto(symbol)
 int symbol;
 {
-    register int i;
-    register int m;
-    register int n;
-    register int default_state;
-    register int max;
+    int i;
+    int m;
+    int n;
+    int default_state;
+    int max;
 
     m = goto_map[symbol];
     n = goto_map[symbol + 1];
@@ -443,14 +443,14 @@ save_column(symbol, default_state)
 int symbol;
 int default_state;
 {
-    register int i;
-    register int m;
-    register int n;
-    register short *sp;
-    register short *sp1;
-    register short *sp2;
-    register int count;
-    register int symno;
+    int i;
+    int m;
+    int n;
+    short *sp;
+    short *sp1;
+    short *sp2;
+    int count;
+    int symno;
 
     m = goto_map[symbol];
     n = goto_map[symbol + 1];
@@ -484,11 +484,11 @@ int default_state;
 static void
 sort_actions()
 {
-  register int i;
-  register int j;
-  register int k;
-  register int t;
-  register int w;
+  int i;
+  int j;
+  int k;
+  int t;
+  int w;
 
   order = NEW2(nvectors, short);
   nentries = 0;
@@ -520,9 +520,9 @@ sort_actions()
 static void
 pack_table()
 {
-    register int i;
-    register int place;
-    register int state;
+    int i;
+    int place;
+    int state;
 
     base = NEW2(nvectors, short);
     pos = NEW2(nentries, short);
@@ -584,13 +584,13 @@ static int
 matching_vector(vector)
 int vector;
 {
-    register int i;
-    register int j;
-    register int k;
-    register int t;
-    register int w;
-    register int match;
-    register int prev;
+    int i;
+    int j;
+    int k;
+    int t;
+    int w;
+    int match;
+    int prev;
 
     i = order[vector];
     if (i >= 2*nstates)
@@ -625,12 +625,12 @@ static int
 pack_vector(vector)
 int vector;
 {
-    register int i, j, k, l;
-    register int t;
-    register int loc;
-    register int ok;
-    register short *from;
-    register short *to;
+    int i, j, k, l;
+    int t;
+    int loc;
+    int ok;
+    short *from;
+    short *to;
 
     i = order[vector];
     t = tally[i];
@@ -701,7 +701,7 @@ int vector;
 static void
 output_base()
 {
-    register int i, j;
+    int i, j;
 
     fprintf(output_file, "const short %ssindex[] = {%39d,", symbol_prefix,
 	    base[0]);
@@ -769,8 +769,8 @@ output_base()
 static void
 output_table()
 {
-    register int i;
-    register int j;
+    int i;
+    int j;
 
     ++outline;
     fprintf(code_file, "#define YYTABLESIZE %d\n", high);
@@ -802,8 +802,8 @@ output_table()
 static void
 output_check()
 {
-    register int i;
-    register int j;
+    int i;
+    int j;
 
     fprintf(output_file, "const short %scheck[] = {%40d,", symbol_prefix,
 	    check[0]);
@@ -833,8 +833,8 @@ static int
 is_C_identifier(name)
 char *name;
 {
-    register char *s;
-    register int c;
+    char *s;
+    int c;
 
     s = name;
     c = *s;
@@ -865,8 +865,8 @@ char *name;
 static void
 output_defines()
 {
-    register int c, i;
-    register char *s;
+    int c, i;
+    char *s;
 
     ++outline;
     fprintf(code_file, "#define YYERRCODE %d\n", symbol_value[1]);
@@ -924,8 +924,8 @@ output_defines()
 static void
 output_stored_text()
 {
-    register int c;
-    register FILE *in, *out;
+    int c;
+    FILE *in, *out;
 
     fclose(text_file);
     text_file = fopen(text_file_name, "r");
@@ -952,8 +952,9 @@ output_stored_text()
 static void
 output_debug()
 {
-    register int i, j, k, max;
+    int i, j, k, max;
     char **symnam, *s;
+    static char eof[] = "end-of-file";
 
     ++outline;
     fprintf(code_file, "#define YYFINAL %d\n", final_state);
@@ -980,7 +981,7 @@ output_debug()
 	symnam[i] = 0;
     for (i = ntokens - 1; i >= 2; --i)
 	symnam[symbol_value[i]] = symbol_name[i];
-    symnam[0] = "end-of-file";
+    symnam[0] = eof;
 
     if (!rflag) ++outline;
     fprintf(output_file, "#if YYDEBUG\n");
@@ -1179,8 +1180,8 @@ output_stype()
 static void
 output_trailing_text()
 {
-    register int c, last;
-    register FILE *in, *out;
+    int c, last;
+    FILE *in, *out;
 
     if (line == 0)
 	return;
@@ -1237,8 +1238,8 @@ output_trailing_text()
 static void
 output_semantic_actions()
 {
-    register int c, last;
-    register FILE *out;
+    int c, last;
+    FILE *out;
 
     fclose(action_file);
     action_file = fopen(action_file_name, "r");
@@ -1275,7 +1276,7 @@ output_semantic_actions()
 static void
 free_itemsets()
 {
-    register core *cp, *next;
+    core *cp, *next;
 
     FREE(state_table);
     for (cp = first_state; cp; cp = next)
@@ -1289,7 +1290,7 @@ free_itemsets()
 static void
 free_shifts()
 {
-    register shifts *sp, *next;
+    shifts *sp, *next;
 
     FREE(shift_table);
     for (sp = first_shift; sp; sp = next)
@@ -1304,7 +1305,7 @@ free_shifts()
 static void
 free_reductions()
 {
-    register reductions *rp, *next;
+    reductions *rp, *next;
 
     FREE(reduction_table);
     for (rp = first_reduction; rp; rp = next)
diff --git a/usr.bin/yacc/reader.c b/usr.bin/yacc/reader.c
index 8fb38faa5198..87eedb372814 100644
--- a/usr.bin/yacc/reader.c
+++ b/usr.bin/yacc/reader.c
@@ -85,6 +85,7 @@ static void copy_action __P((void));
 static void copy_ident __P((void));
 static void copy_text __P((void));
 static void copy_union __P((void));
+static void declare_expect __P((int));
 static void declare_start __P((void));
 static void declare_tokens __P((int));
 static void declare_types __P((void));
@@ -133,9 +134,9 @@ int c;
 static void
 get_line()
 {
-    register FILE *f = input_file;
-    register int c;
-    register int i;
+    FILE *f = input_file;
+    int c;
+    int i;
 
     if (saw_eof || (c = getc(f)) == EOF)
     {
@@ -180,7 +181,7 @@ get_line()
 static char *
 dup_line()
 {
-    register char *p, *s, *t;
+    char *p, *s, *t;
 
     if (line == 0) return (0);
     s = line;
@@ -198,7 +199,7 @@ dup_line()
 static void
 skip_comment()
 {
-    register char *s;
+    char *s;
 
     int st_lineno = lineno;
     char *st_line = dup_line();
@@ -229,7 +230,7 @@ skip_comment()
 static int
 nextc()
 {
-    register char *s;
+    char *s;
 
     if (line == 0)
     {
@@ -291,7 +292,7 @@ nextc()
 static int
 keyword()
 {
-    register int c;
+    int c;
     char *t_cptr = cptr;
 
     c = *++cptr;
@@ -357,8 +358,8 @@ keyword()
 static void
 copy_ident()
 {
-    register int c;
-    register FILE *f = output_file;
+    int c;
+    FILE *f = output_file;
 
     c = nextc();
     if (c == EOF) unexpected_EOF();
@@ -387,9 +388,9 @@ copy_ident()
 static void
 copy_text()
 {
-    register int c;
+    int c;
     int quote;
-    register FILE *f = text_file;
+    FILE *f = text_file;
     int need_newline = 0;
     int t_lineno = lineno;
     char *t_line = dup_line();
@@ -519,7 +520,7 @@ copy_text()
 static void
 copy_union()
 {
-    register int c;
+    int c;
     int quote;
     int depth;
     int u_lineno = lineno;
@@ -674,11 +675,11 @@ int c;
 static bucket *
 get_literal()
 {
-    register int c, quote;
-    register int i;
-    register int n;
-    register char *s;
-    register bucket *bp;
+    int c, quote;
+    int i;
+    int n;
+    char *s;
+    bucket *bp;
     int s_lineno = lineno;
     char *s_line = dup_line();
     char *s_cptr = s_line + (cptr - line);
@@ -835,7 +836,7 @@ char *name;
 static bucket *
 get_name()
 {
-    register int c;
+    int c;
 
     cinc = 0;
     for (c = *cptr; IS_IDENT(c); c = *++cptr)
@@ -851,8 +852,8 @@ get_name()
 static int
 get_number()
 {
-    register int c;
-    register int n;
+    int c;
+    int n;
 
     n = 0;
     for (c = *cptr; isdigit(c); c = *++cptr)
@@ -865,9 +866,9 @@ get_number()
 static char *
 get_tag()
 {
-    register int c;
-    register int i;
-    register char *s;
+    int c;
+    int i;
+    char *s;
     int t_lineno = lineno;
     char *t_line = dup_line();
     char *t_cptr = t_line + (cptr - line);
@@ -917,8 +918,8 @@ static void
 declare_tokens(assoc)
 int assoc;
 {
-    register int c;
-    register bucket *bp;
+    int c;
+    bucket *bp;
     int value;
     char *tag = 0;
 
@@ -985,7 +986,7 @@ static void
 declare_expect(assoc)
 int assoc;
 {
-    register int c;
+    int c;
 
     if (assoc != EXPECT) ++prec;
 
@@ -1024,8 +1025,8 @@ int assoc;
 static void
 declare_types()
 {
-    register int c;
-    register bucket *bp;
+    int c;
+    bucket *bp;
     char *tag;
 
     c = nextc();
@@ -1053,8 +1054,8 @@ declare_types()
 static void
 declare_start()
 {
-    register int c;
-    register bucket *bp;
+    int c;
+    bucket *bp;
 
     c = nextc();
     if (c == EOF) unexpected_EOF();
@@ -1072,7 +1073,7 @@ declare_start()
 static void
 read_declarations()
 {
-    register int c, k;
+    int c, k;
 
     cache_size = 256;
     cache = MALLOC(cache_size);
@@ -1180,8 +1181,8 @@ expand_rules()
 static void
 advance_to_start()
 {
-    register int c;
-    register bucket *bp;
+    int c;
+    bucket *bp;
     char *s_cptr;
     int s_lineno;
 
@@ -1230,7 +1231,7 @@ advance_to_start()
 
 static void
 start_rule(bp, s_lineno)
-register bucket *bp;
+bucket *bp;
 int s_lineno;
 {
     if (bp->class == TERM)
@@ -1247,7 +1248,7 @@ int s_lineno;
 static void
 end_rule()
 {
-    register int i;
+    int i;
 
     if (!last_was_action && plhs[nrules]->tag)
     {
@@ -1267,7 +1268,7 @@ end_rule()
 static void
 insert_empty_rule()
 {
-    register bucket *bp, **bpp;
+    bucket *bp, **bpp;
 
     assert(cache);
     sprintf(cache, "$$%d", ++gensym);
@@ -1297,8 +1298,8 @@ insert_empty_rule()
 static void
 add_symbol()
 {
-    register int c;
-    register bucket *bp;
+    int c;
+    bucket *bp;
     int s_lineno = lineno;
 
     c = *cptr;
@@ -1329,12 +1330,12 @@ add_symbol()
 static void
 copy_action()
 {
-    register int c;
-    register int i, n;
+    int c;
+    int i, n;
     int depth;
     int quote;
     char *tag;
-    register FILE *f = action_file;
+    FILE *f = action_file;
     int a_lineno = lineno;
     char *a_line = dup_line();
     char *a_cptr = a_line + (cptr - line);
@@ -1553,8 +1554,8 @@ copy_action()
 static int
 mark_symbol()
 {
-    register int c;
-    register bucket *bp = NULL;
+    int c;
+    bucket *bp = NULL;
 
     c = cptr[1];
     if (c == '%' || c == '\\')
@@ -1597,7 +1598,7 @@ mark_symbol()
 static void
 read_grammar()
 {
-    register int c;
+    int c;
 
     initialize_grammar();
     advance_to_start();
@@ -1631,7 +1632,7 @@ read_grammar()
 static void
 free_tags()
 {
-    register int i;
+    int i;
 
     if (tag_table == 0) return;
 
@@ -1647,8 +1648,8 @@ free_tags()
 static void
 pack_names()
 {
-    register bucket *bp;
-    register char *p, *s, *t;
+    bucket *bp;
+    char *p, *s, *t;
 
     name_pool_size = 13;  /* 13 == sizeof("$end") + sizeof("$accept") */
     for (bp = first_symbol; bp; bp = bp->next)
@@ -1673,7 +1674,7 @@ pack_names()
 static void
 check_symbols()
 {
-    register bucket *bp;
+    bucket *bp;
 
     if (goal->class == UNKNOWN)
 	undefined_goal(goal->name);
@@ -1692,9 +1693,9 @@ check_symbols()
 static void
 pack_symbols()
 {
-    register bucket *bp;
-    register bucket **v;
-    register int i, j, k, n;
+    bucket *bp;
+    bucket **v;
+    int i, j, k, n;
 
     nsyms = 2;
     ntokens = 1;
@@ -1817,8 +1818,8 @@ pack_symbols()
 static void
 pack_grammar()
 {
-    register int i, j;
-    int assoc, prec;
+    int i, j;
+    int assoc, preced;
 
     ritem = (short *) MALLOC(nitems*sizeof(short));
     if (ritem == 0) no_space();
@@ -1848,13 +1849,13 @@ pack_grammar()
 	rlhs[i] = plhs[i]->index;
 	rrhs[i] = j;
 	assoc = TOKEN;
-	prec = 0;
+	preced = 0;
 	while (pitem[j])
 	{
 	    ritem[j] = pitem[j]->index;
 	    if (pitem[j]->class == TERM)
 	    {
-		prec = pitem[j]->prec;
+		preced = pitem[j]->prec;
 		assoc = pitem[j]->assoc;
 	    }
 	    ++j;
@@ -1863,7 +1864,7 @@ pack_grammar()
 	++j;
 	if (rprec[i] == UNDEFINED)
 	{
-	    rprec[i] = prec;
+	    rprec[i] = preced;
 	    rassoc[i] = assoc;
 	}
     }
@@ -1877,9 +1878,9 @@ pack_grammar()
 static void
 print_grammar()
 {
-    register int i, j, k;
+    int i, j, k;
     int spacing = 0;
-    register FILE *f = verbose_file;
+    FILE *f = verbose_file;
 
     if (!vflag) return;
 
diff --git a/usr.bin/yacc/skeleton.c b/usr.bin/yacc/skeleton.c
index aba2abd45bac..e8ae5542a996 100644
--- a/usr.bin/yacc/skeleton.c
+++ b/usr.bin/yacc/skeleton.c
@@ -52,7 +52,7 @@ static char const sccsid[] = "@(#)skeleton.c	5.8 (Berkeley) 4/29/95";
 /*  the body either are not useful outside of semantic actions or	*/
 /*  are conditional.							*/
 
-char *banner[] =
+const char *banner[] =
 {
     "#ifndef lint",
     "static char const ",
@@ -76,7 +76,7 @@ char *banner[] =
 };
 
 
-char *tables[] =
+const char *tables[] =
 {
     "extern const short yylhs[];",
     "extern const short yylen[];",
@@ -95,7 +95,7 @@ char *tables[] =
 };
 
 
-char *header[] =
+const char *header[] =
 {
     "#if YYDEBUG",
     "#include <stdio.h>",
@@ -128,7 +128,7 @@ char *header[] =
 };
 
 
-char *body[] =
+const char *body[] =
 {
     "/* allocate initial stack or double stack size, up to YYMAXDEPTH */",
     "static int yygrowstack()",
@@ -191,9 +191,9 @@ char *body[] =
     "yyparse (YYPARSE_PARAM_ARG)",
     "    YYPARSE_PARAM_DECL",
     "{",
-    "    register int yym, yyn, yystate;",
+    "    int yym, yyn, yystate;",
     "#if YYDEBUG",
-    "    register const char *yys;",
+    "    const char *yys;",
     "",
     "    if ((yys = getenv(\"YYDEBUG\")))",
     "    {",
@@ -330,7 +330,7 @@ char *body[] =
 };
 
 
-char *trailer[] =
+const char *trailer[] =
 {
     "    }",
     "    yyssp -= yym;",
@@ -394,12 +394,12 @@ char *trailer[] =
 
 void
 write_section(section)
-char *section[];
+const char *section[];
 {
-    register int c;
-    register int i;
-    register char *s;
-    register FILE *f;
+    int c;
+    int i;
+    const char *s;
+    FILE *f;
 
     f = code_file;
     for (i = 0; (s = section[i]); ++i)
diff --git a/usr.bin/yacc/symtab.c b/usr.bin/yacc/symtab.c
index f155021bb68e..f566845cf074 100644
--- a/usr.bin/yacc/symtab.c
+++ b/usr.bin/yacc/symtab.c
@@ -49,7 +49,7 @@ static char const sccsid[] = "@(#)symtab.c	5.3 (Berkeley) 6/1/90";
 
 #define	TABLE_SIZE 1024
 
-static int hash __P((char *));
+static int hash __P((const char *));
 
 bucket **symbol_table;
 bucket *first_symbol;
@@ -58,10 +58,10 @@ bucket *last_symbol;
 
 static int
 hash(name)
-char *name;
+const char *name;
 {
-    register char *s;
-    register int c, k;
+    const char *s;
+    int c, k;
 
     assert(name && *name);
     s = name;
@@ -75,9 +75,9 @@ char *name;
 
 bucket *
 make_bucket(name)
-char *name;
+const char *name;
 {
-    register bucket *bp;
+    bucket *bp;
 
     assert(name);
     bp = (bucket *) MALLOC(sizeof(bucket));
@@ -104,7 +104,7 @@ bucket *
 lookup(name)
 char *name;
 {
-    register bucket *bp, **bpp;
+    bucket *bp, **bpp;
 
     bpp = symbol_table + hash(name);
     bp = *bpp;
@@ -127,8 +127,8 @@ char *name;
 void
 create_symbol_table()
 {
-    register int i;
-    register bucket *bp;
+    int i;
+    bucket *bp;
 
     symbol_table = (bucket **) MALLOC(TABLE_SIZE*sizeof(bucket *));
     if (symbol_table == 0) no_space();
@@ -156,7 +156,7 @@ free_symbol_table()
 void
 free_symbols()
 {
-    register bucket *p, *q;
+    bucket *p, *q;
 
     for (p = first_symbol; p; p = q)
     {
diff --git a/usr.bin/yacc/verbose.c b/usr.bin/yacc/verbose.c
index 69ce15e1d271..17ac82c51ed9 100644
--- a/usr.bin/yacc/verbose.c
+++ b/usr.bin/yacc/verbose.c
@@ -50,8 +50,8 @@ static void print_conflicts __P((int));
 static void print_core __P((int));
 static void print_gotos __P((int));
 static void print_nulls __P((int));
-static void print_reductions __P((register action *, register int));
-static void print_shifts __P((register action *));
+static void print_reductions __P((action *, register int));
+static void print_shifts __P((action *));
 static void print_state __P((int));
 
 static short *null_rules;
@@ -59,7 +59,7 @@ static short *null_rules;
 void
 verbose()
 {
-    register int i;
+    int i;
 
     if (!vflag) return;
 
@@ -84,8 +84,8 @@ verbose()
 static void
 log_unused()
 {
-    register int i;
-    register short *p;
+    int i;
+    short *p;
 
     fprintf(verbose_file, "\n\nRules never reduced:\n");
     for (i = 3; i < nrules; ++i)
@@ -104,7 +104,7 @@ log_unused()
 static void
 log_conflicts()
 {
-    register int i;
+    int i;
 
     fprintf(verbose_file, "\n\n");
     for (i = 0; i < nstates; i++)
@@ -149,8 +149,8 @@ static void
 print_conflicts(state)
 int state;
 {
-    register int symbol, act = 0, number = 0;
-    register action *p;
+    int symbol, act = 0, number = 0;
+    action *p;
 
     symbol = -1;
     for (p = parser[state]; p; p = p->next)
@@ -198,12 +198,12 @@ static void
 print_core(state)
 int state;
 {
-    register int i;
-    register int k;
-    register int rule;
-    register core *statep;
-    register short *sp;
-    register short *sp1;
+    int i;
+    int k;
+    int rule;
+    core *statep;
+    short *sp;
+    short *sp1;
 
     statep = state_table[state];
     k = statep->nitems;
@@ -235,8 +235,8 @@ static void
 print_nulls(state)
 int state;
 {
-    register action *p;
-    register int i, j, k, nnulls;
+    action *p;
+    int i, j, k, nnulls;
 
     nnulls = 0;
     for (p = parser[state]; p; p = p->next)
@@ -280,9 +280,9 @@ static void
 print_actions(stateno)
 int stateno;
 {
-    register action *p;
-    register shifts *sp;
-    register int as;
+    action *p;
+    shifts *sp;
+    int as;
 
     if (stateno == final_state)
 	fprintf(verbose_file, "\t$end  accept\n");
@@ -306,10 +306,10 @@ int stateno;
 
 static void
 print_shifts(p)
-register action *p;
+action *p;
 {
-    register int count;
-    register action *q;
+    int count;
+    action *q;
 
     count = 0;
     for (q = p; q; q = q->next)
@@ -331,12 +331,12 @@ register action *p;
 
 
 static void
-print_reductions(p, defred)
-register action *p;
-register int defred;
+print_reductions(p, defreduct)
+action *p;
+int defreduct;
 {
-    register int k, anyreds;
-    register action *q;
+    int k, anyreds;
+    action *q;
 
     anyreds = 0;
     for (q = p; q ; q = q->next)
@@ -354,7 +354,7 @@ register int defred;
     {
 	for (; p; p = p->next)
 	{
-	    if (p->action_code == REDUCE && p->number != defred)
+	    if (p->action_code == REDUCE && p->number != defreduct)
 	    {
 		k = p->number - 2;
 		if (p->suppressed == 0)
@@ -363,8 +363,8 @@ register int defred;
 	    }
 	}
 
-        if (defred > 0)
-	    fprintf(verbose_file, "\t.  reduce %d\n", defred - 2);
+        if (defreduct > 0)
+	    fprintf(verbose_file, "\t.  reduce %d\n", defreduct - 2);
     }
 }
 
@@ -373,17 +373,17 @@ static void
 print_gotos(stateno)
 int stateno;
 {
-    register int i, k;
-    register int as;
-    register short *to_state;
-    register shifts *sp;
+    int i, k;
+    int as;
+    short *tostate;
+    shifts *sp;
 
     putc('\n', verbose_file);
     sp = shift_table[stateno];
-    to_state = sp->shift;
+    tostate = sp->shift;
     for (i = 0; i < sp->nshifts; ++i)
     {
-	k = to_state[i];
+	k = tostate[i];
 	as = accessing_symbol[k];
 	if (ISVAR(as))
 	    fprintf(verbose_file, "\t%s  goto %d\n", symbol_name[as], k);
diff --git a/usr.bin/yacc/warshall.c b/usr.bin/yacc/warshall.c
index 37408c0b3fa9..a1e6d45b66e3 100644
--- a/usr.bin/yacc/warshall.c
+++ b/usr.bin/yacc/warshall.c
@@ -49,15 +49,15 @@ transitive_closure(R, n)
 unsigned *R;
 int n;
 {
-    register int rowsize;
-    register unsigned i;
-    register unsigned *rowj;
-    register unsigned *rp;
-    register unsigned *rend;
-    register unsigned *ccol;
-    register unsigned *relend;
-    register unsigned *cword;
-    register unsigned *rowi;
+    int rowsize;
+    unsigned i;
+    unsigned *rowj;
+    unsigned *rp;
+    unsigned *rend;
+    unsigned *ccol;
+    unsigned *relend;
+    unsigned *cword;
+    unsigned *rowi;
 
     rowsize = WORDSIZE(n);
     relend = R + n*rowsize;
@@ -102,10 +102,10 @@ reflexive_transitive_closure(R, n)
 unsigned *R;
 int n;
 {
-    register int rowsize;
-    register unsigned i;
-    register unsigned *rp;
-    register unsigned *relend;
+    int rowsize;
+    unsigned i;
+    unsigned *rp;
+    unsigned *relend;
 
     transitive_closure(R, n);