diff --git a/ports/arm/syscalls.c b/ports/arm/syscalls.c
index db3e6bd..5933531 100644
--- a/ports/arm/syscalls.c
+++ b/ports/arm/syscalls.c
@@ -65,6 +65,7 @@ extern int _open(const char *name, int flags, int mode) __attribute__((weak));
 extern int _read(int file, char *ptr, int len) __attribute__((weak));
 extern caddr_t _sbrk(int incr) __attribute__((weak));
 extern int _write(int file, char *ptr, int len) __attribute__((weak));
+extern int _exit(int val) __attribute__((weak));
 
 
 /**
@@ -209,3 +210,14 @@ caddr_t _sbrk(int incr)
     return (caddr_t)prev_heap_end;
 }
 
+/**
+ * \b _exit
+ *
+ * Simple stub implementation, exit() not needed or implemented.
+ *
+ */
+int _exit(int val)
+{
+	return -1;
+}
+