diff --git a/newlib/libc/sys/sysnecv850/_exit.c b/newlib/libc/sys/sysnecv850/_exit.c
index 44d4132bd..7e1b09262 100644
--- a/newlib/libc/sys/sysnecv850/_exit.c
+++ b/newlib/libc/sys/sysnecv850/_exit.c
@@ -23,7 +23,7 @@ static void _do_dtors()
 }
 
 
-void _exit (n)
+void _exit (int n)
 {
   /* Destructors should be done earlier because they need to be done before the
      files are closed, but here is better than nowhere (and this balances the
diff --git a/newlib/libc/sys/sysnecv850/getpid.c b/newlib/libc/sys/sysnecv850/getpid.c
index 32ac7fbfb..f0fc4d895 100644
--- a/newlib/libc/sys/sysnecv850/getpid.c
+++ b/newlib/libc/sys/sysnecv850/getpid.c
@@ -9,7 +9,8 @@ int __trap0 (int function, int p1, int p2, int p3);
 
 #define TRAP0(f, p1, p2, p3) __trap0(f, (int)(p1), (int)(p2), (int)(p3))
 
-_getpid (n)
+int
+_getpid (int n)
 {
   return 1;
 }
diff --git a/newlib/libc/sys/sysnecv850/isatty.c b/newlib/libc/sys/sysnecv850/isatty.c
index 248ab5248..6e4f205f0 100644
--- a/newlib/libc/sys/sysnecv850/isatty.c
+++ b/newlib/libc/sys/sysnecv850/isatty.c
@@ -9,8 +9,8 @@ int __trap0 (int function, int p1, int p2, int p3);
 
 #define TRAP0(f, p1, p2, p3) __trap0(f, (int)(p1), (int)(p2), (int)(p3))
 
-_isatty (fd)
-     int fd;
+int
+_isatty (int fd)
 {
   return 1;
 }
diff --git a/newlib/libc/sys/sysnecv850/kill.c b/newlib/libc/sys/sysnecv850/kill.c
index 34e5db793..562eaf6c7 100644
--- a/newlib/libc/sys/sysnecv850/kill.c
+++ b/newlib/libc/sys/sysnecv850/kill.c
@@ -10,9 +10,8 @@ int __trap0 (int function, int p1, int p2, int p3);
 
 #define TRAP0(f, p1, p2, p3) __trap0(f, (int)(p1), (int)(p2), (int)(p3))
 
-_kill (pid, sig)
-     pid_t pid;
-     int sig;
+int
+_kill (pid_t pid, int sig)
 {
   return TRAP0 (SYS_exit, 0xdead0000 | sig, 0, 0);
 }
diff --git a/newlib/libc/sys/sysnecv850/read.c b/newlib/libc/sys/sysnecv850/read.c
index b55d1cb9e..5ae2c9799 100644
--- a/newlib/libc/sys/sysnecv850/read.c
+++ b/newlib/libc/sys/sysnecv850/read.c
@@ -9,6 +9,7 @@ int __trap0 (int function, int p1, int p2, int p3);
 
 #define TRAP0(f, p1, p2, p3) __trap0(f, (int)(p1), (int)(p2), (int)(p3))
 
+int
 _read (int file,
        char *ptr,
        int len)
diff --git a/newlib/libc/sys/sysnecv850/sbrk.c b/newlib/libc/sys/sysnecv850/sbrk.c
index 2893c322f..b5673d467 100644
--- a/newlib/libc/sys/sysnecv850/sbrk.c
+++ b/newlib/libc/sys/sysnecv850/sbrk.c
@@ -2,7 +2,9 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include "sys/syscall.h"
+#include <stdlib.h>
 
+extern int _write (int, char *, int);
 caddr_t
 _sbrk (int incr)
 {