Fix compiler warnings.

Declare functions before calling them.  Declare all return types.

sl.c

@@ -39,6 +39,14 @@
 #include <unistd.h>
 #include "sl.h"
 
+void add_smoke(int y, int x);
+void add_man(int y, int x);
+int add_C51(int x);
+int add_D51(int x);
+int add_sl(int x);
+void option(char *str);
+int my_mvaddstr(int y, int x, char *str);
+
 int ACCIDENT  = 0;
 int LOGO      = 0;
 int FLY       = 0;
@@ -145,7 +153,7 @@ int add_sl(int x)
 }
 
 
-add_D51(int x)
+int add_D51(int x)
 {
     static char *d51[D51PATTERNS][D51HIGHT + 1]
         = {{D51STR1, D51STR2, D51STR3, D51STR4, D51STR5, D51STR6, D51STR7,
@@ -185,7 +193,7 @@ add_D51(int x)
     return OK;
 }
 
-add_C51(int x)
+int add_C51(int x)
 {
     static char *c51[C51PATTERNS][C51HIGHT + 1]
         = {{C51STR1, C51STR2, C51STR3, C51STR4, C51STR5, C51STR6, C51STR7,
@@ -226,7 +234,7 @@ add_C51(int x)
 }
 
 
-int add_man(int y, int x)
+void add_man(int y, int x)
 {
     static char *man[2][2] = {{"", "(O)"}, {"Help!", "\\O/"}};
     int i;
@@ -237,7 +245,7 @@ int add_man(int y, int x)
 }
 
 
-int add_smoke(int y, int x)
+void add_smoke(int y, int x)
 #define SMOKEPTNS        16
 {
     static struct smokes {