https://bugs.gentoo.org/879041

--- teco/te_defs.h
+++ teco/te_defs.h
@@ -320,7 +320,72 @@
 extern char mapch[], mapch_l[];         /* char mapping tables              */
 extern unsigned char spec_chars[];      /* special character table          */
 
-extern char skipto(), getcmdc(), getcmdc0();    /* routines that return chars */
+extern void block_inter(int func);
+extern void crlf(void);
+extern void delete1(int nchars);
+extern void dly_free_blist(struct buffcell *p);
+extern void do_ctlp(void);
+extern void do_e(void);
+extern void do_f(void);
+extern void do_o(void);
+extern void do_window(int ref_flag);
+extern void exec_cmds1(void);
+extern void exec_cmdstr(void);
+extern void find_enditer(void);
+extern void free_blist(struct buffcell *p);
+extern void insert1(void);
+extern void insert2(int count);
+extern void kill_output(struct outfiledata *outptr);
+extern void make_buffer(struct qh *p);
+extern void movenchars(struct qp *from, struct qp *to, int n);
+extern void moveuntil(struct qp *from, struct qp *to, char c,
+		      int *n, int max, int trace);
+extern void panic(void);
+extern void pop_iteration(int arg);
+extern void retype_cmdstr(char c);
+extern void set_pointer(int pos, struct qp *ptr);
+extern void set_term_par(int lines, int cols);
+extern void set_var(int *arg);
+extern void setup_tty(int arg);
+extern void te_fx(void);
+extern void type_char(char c);
+extern void vt(int func);
+extern void window(int arg);
+extern void write_file(struct qp *wbuff, int nchars, int ffsw);
+extern char getcmdc(int trace);
+extern char getcmdc0(int trace);
+extern char gettty(void);
+extern char skipto(int arg);
+extern int backc(struct qp *arg);
+extern int build_string(struct qh *sbuff);
+extern int do_en(void);
+extern int do_eq(void);
+extern int do_eq1(char *shell);
+extern int do_fb(void);
+extern int do_glob(struct qh *gbuff);
+extern int do_nsearch(char arg);
+extern int do_search(int count);
+extern int end_search(int result);
+extern int fwdc(struct qp *arg);
+extern int fwdcx(struct qp *arg);
+extern int get_value(int d);
+extern int getqspec(int fors, char c);
+extern int gettty_nowait(void);
+extern int line_args(int d, struct qp *p);
+extern int lines(int arg);
+extern int peekcmdc(char arg);
+extern int read_cmdstr(void);
+extern int read_file(struct qp *rbuff, int *nchars, int endsw);
+extern int read_filename(int flag, char func);
+extern int read_stream(FILE *file, int *ff_found, struct qp *rbuff,
+		       int *nchars, int endsw, int crlf_sw, int ff_sw);
+extern int setup_search(void);
+extern int srch_cmp(void);
+extern int tgetent(char *bp, const char *name);
+extern int tgetnum(const char *id);
+extern int w_lines(int n, struct qp *ps, struct qp *pd);
+extern int w_setptr(int loc, struct qp *pp);
+extern int w_overflow(int wd);
 
 extern FILE *eisw;                      /* indirect command file pointer    */
 extern FILE *fopen();
--- teco/te_exec2.c
+++ teco/te_exec2.c
@@ -8,10 +8,15 @@
 /* version for multiple buffers  04/19/89 11.29 */
 
 #include "te_defs.h"
+#include <unistd.h>
 #include <sys/wait.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 
+/* these shouldn't be necessary, since we include unistd.h and sys/stat.h */
+extern int fchmod(int fd, mode_t mode);
+extern pid_t vfork(void);
+
 void do_en_next(), set_var(), write_file(), write_stream();
 void kill_output(), pop_iteration(), find_enditer(), find_endcond();
 
--- teco/te_fxstub.c
+++ teco/te_fxstub.c
@@ -10,7 +10,7 @@
 
 #include "te_defs.h"
 
-te_fx()
+void te_fx()
 {
     ERROR(E_IFC);
 }
--- teco/te_main.c
+++ teco/te_main.c
@@ -46,6 +46,7 @@
 
 void cleanup(), print_string(), save_args(), read_startup(), get_term_par();
 
+int
 main(argc, argv)
     int argc;           /* arg count */
     char *argv[];       /* array of string pointers */
--- teco/te_rdcmd.c
+++ teco/te_rdcmd.c
@@ -7,6 +7,7 @@
 #include "te_defs.h"
 
 void retype_cmdstr(char c);
+int find_lasteol(void);
 int ccount;             /* count of chars read in */
 
 int read_cmdstr()
--- teco/te_srch.c
+++ teco/te_srch.c
@@ -156,7 +156,7 @@
 /* routine to do N, _, E_ searches:  search, if search fails, then get  */
 /* next page and continue                                               */
 
-do_nsearch(arg)
+int do_nsearch(arg)
     char arg;       /* arg is 'n', '_', or 'e' to define which search */
     {
     int scount;     /* search count */
--- teco/te_utils.c
+++ teco/te_utils.c
@@ -144,7 +144,7 @@
     return(1);
     }
 
-fwdcx(arg)
+int fwdcx(arg)
     struct qp *arg;
     {
     if ((*arg).c >= CELLSIZE-1)     /* test char count for max */