diff --git a/lang/cem/cpp.ansi/init.c b/lang/cem/cpp.ansi/init.c
index 3953609b5..810b4204c 100644
--- a/lang/cem/cpp.ansi/init.c
+++ b/lang/cem/cpp.ansi/init.c
@@ -34,7 +34,6 @@ struct mkey	{
 	{0,		K_UNKNOWN}
 };
 
-char *strcpy();
 char *sprint();
 
 init_pp()
diff --git a/mach/proto/cg/compute.c b/mach/proto/cg/compute.c
index 26570f49d..49d2381fa 100644
--- a/mach/proto/cg/compute.c
+++ b/mach/proto/cg/compute.c
@@ -73,7 +73,7 @@ char opdesc[] = {
 	LLDEF,			/* EX_REGVAR */
 };
 
-string salloc(),strcpy(),strcat();
+string salloc();
 
 string mycat(s1,s2) string s1,s2; {
 	register string s;
diff --git a/modules/src/em_code/em.c b/modules/src/em_code/em.c
index f13ab28dc..cf6948bff 100644
--- a/modules/src/em_code/em.c
+++ b/modules/src/em_code/em.c
@@ -31,7 +31,6 @@ File		*C_ofp;
 #ifndef INCORE
 File		*C_tfr;
 char		*C_tmpfile;
-char		*strcpy(), *strcat();
 char		*C_ibuf = 0;
 long		C_current_out;
 #endif
diff --git a/modules/src/em_opt/outputdfa.c b/modules/src/em_opt/outputdfa.c
index cebdd958c..c58c966b9 100644
--- a/modules/src/em_opt/outputdfa.c
+++ b/modules/src/em_opt/outputdfa.c
@@ -2,6 +2,7 @@
 static char rcsidp5[] = "$Id$";
 #endif
 
+#include <string.h>
 #include "parser.h"
 #include "Lpars.h"
 
@@ -40,7 +41,6 @@ PRIVATE
 openofile(filename)
 	char *filename;
 {
-	char *strcpy(), *strcat();
 	strcpy(ofilename,filename);
 	strcpy(ofiletemp,filename);
 	strcat(ofiletemp,".new");
diff --git a/util/byacc/defs.h b/util/byacc/defs.h
index 5eef5c55a..8be3d80db 100644
--- a/util/byacc/defs.h
+++ b/util/byacc/defs.h
@@ -1,6 +1,8 @@
 #include <assert.h>
 #include <ctype.h>
 #include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
 
 /*  machine dependent definitions			*/
 /*  the following definitions are for the VAX		*/
@@ -269,17 +271,3 @@ extern short final_state;
 extern char *allocate();
 extern bucket *lookup();
 extern bucket *make_bucket();
-
-
-/* system variables */
-
-extern int errno;
-
-
-/* system functions */
-
-extern void free();
-extern char *calloc();
-extern char *malloc();
-extern char *realloc();
-extern char *strcpy();
diff --git a/util/cmisc/cclash.c b/util/cmisc/cclash.c
index 44fa6cbe6..1bc8c68b3 100644
--- a/util/cmisc/cclash.c
+++ b/util/cmisc/cclash.c
@@ -30,6 +30,7 @@
 */
 
 #include <stdio.h>
+#include <string.h>
 
 #define DEF_LENGTH	8
 
@@ -184,8 +185,6 @@ char *
 Salloc(str)
 	char *str;
 {
-	char *strcpy();
-
 	if (str == 0)
 		str = "";
 
diff --git a/util/cmisc/cid.c b/util/cmisc/cid.c
index a21a4d940..b09136e33 100644
--- a/util/cmisc/cid.c
+++ b/util/cmisc/cid.c
@@ -14,6 +14,7 @@
 */
 
 #include <stdio.h>
+#include <string.h>
 
 #ifndef DEF_LENGTH
 #define DEF_LENGTH	8
@@ -159,8 +160,6 @@ char *
 Salloc(str)
 	char *str;
 {
-	char *strcpy();
-
 	if (str == 0) {
 		str = "";
 	}
diff --git a/util/cmisc/mkdep.c b/util/cmisc/mkdep.c
index 8e14ae2dc..065678929 100644
--- a/util/cmisc/mkdep.c
+++ b/util/cmisc/mkdep.c
@@ -10,6 +10,7 @@
  */
 
 #include <stdio.h>
+#incoude <string.h>
 
 #define BSIZ 1024
 char *prog;
@@ -64,7 +65,6 @@ add_name(nm)
 	char *nm;
 {
 	struct namelist *nlp = nl, *lnlp = 0, *nnlp;
-	char *strcpy();
 
 	while (nlp) {
 		register i = strcmp(nm, nlp->name);
diff --git a/util/cmisc/prid.c b/util/cmisc/prid.c
index e81efe59e..79818bb27 100644
--- a/util/cmisc/prid.c
+++ b/util/cmisc/prid.c
@@ -14,6 +14,7 @@
 */
 
 #include <stdio.h>
+#include <string.h>
 
 extern char *ProgName;
 
@@ -101,8 +102,6 @@ char *
 Salloc(str)
 	char *str;
 {
-	char *strcpy();
-
 	if (str == 0)
 		str = "";
 
diff --git a/util/cpp/LLlex.c b/util/cpp/LLlex.c
index 93602e9d9..4bba8c0a2 100644
--- a/util/cpp/LLlex.c
+++ b/util/cpp/LLlex.c
@@ -5,6 +5,7 @@
 /* $Id$ */
 /*		    L E X I C A L   A N A L Y Z E R			*/
 
+#include	<string.h>
 #include	"idfsize.h"
 #include	"numsize.h"
 #include	"strsize.h"
@@ -26,7 +27,6 @@ int AccDefined = 0;		/* accept "defined(...)"		*/
 int UnknownIdIsZero = 0;	/* interpret unknown id as integer 0	*/
 
 char *string_token();
-char *strcpy();
 
 PushLex()
 {
diff --git a/util/cpp/init.c b/util/cpp/init.c
index 61e2ac809..8a7273711 100644
--- a/util/cpp/init.c
+++ b/util/cpp/init.c
@@ -5,6 +5,7 @@
  */
 /* PREPROCESSOR: INITIALIZATION ROUTINES */
 
+#include	<string.h>
 #include	<system.h>
 #include	<alloc.h>
 #include	"class.h"
@@ -30,8 +31,6 @@ PRIVATE struct mkey	{
 	{0,		K_UNKNOWN}
 };
 
-char *strcpy();
-
 EXPORT
 init_pp()
 {
diff --git a/util/cpp/replace.c b/util/cpp/replace.c
index 1951e1bda..2c3eec830 100644
--- a/util/cpp/replace.c
+++ b/util/cpp/replace.c
@@ -20,7 +20,6 @@
 #include	"class.h"
 #include	"interface.h"
 
-char *strcpy(), *strcat();
 char *long2str();
 extern int InputLevel;
 
diff --git a/util/int/log.c b/util/int/log.c
index 517d90a88..add9f356a 100644
--- a/util/int/log.c
+++ b/util/int/log.c
@@ -5,6 +5,7 @@
 /* $Id$ */
 
 #include	<stdio.h>
+#include	<string.h>
 #if __STDC__
 #include	<stdarg.h>
 #else
@@ -17,9 +18,6 @@
 
 #ifdef	LOGGING
 
-extern int strlen();
-extern char *strcpy();
-
 extern long mess_id;			/* from io.c */
 extern FILE *fcreat_high();		/* from io.c */
 
diff --git a/util/int/main.c b/util/int/main.c
index 3681d915f..a3fd17b4f 100644
--- a/util/int/main.c
+++ b/util/int/main.c
@@ -5,6 +5,8 @@
 /* $Id$ */
 
 #include	<stdio.h>
+#include	<stdlib.h>
+#include	<string.h>
 #include	<setjmp.h>
 
 #include	<em_abs.h>
@@ -20,10 +22,6 @@
 #include	"opcode.h"
 #include	"rsb.h"
 
-extern int atoi();
-extern long atol();
-extern char *strcpy();
-
 char mess_file[64] = "int.mess";	/* name of message file */
 
 jmp_buf trapbuf;