fix missing prototype and printf warnings

--- a/lib/argmatch.c
+++ b/lib/argmatch.c
@@ -21,6 +21,7 @@
 #include "argmatch.h"
 
 #include <stdio.h>
+#include <stdlib.h>
 #ifdef STDC_HEADERS
 # include <string.h>
 #endif
--- a/lib/encoding.c
+++ b/lib/encoding.c
@@ -790,7 +790,7 @@ dump_encoding_setup (FILE * stream,
   /* Create the dictionary and fill it */
   fprintf (stream, "%% Dictionary for %s support\n",
 	  encoding->name);
-  fprintf (stream, "/%sdict %d dict begin\n", encoding->key, nb);
+  fprintf (stream, "/%sdict %zu dict begin\n", encoding->key, nb);
   for (i = 0 ; i < nb ; i++)
     fprintf (stream, "  /f%s %sEncoding /%s reencode_font\n",
 	     font_names [i],
--- a/lib/output.c
+++ b/lib/output.c
@@ -84,7 +84,7 @@ new_derivation (enum derivation_type type)
 static void
 derivation_self_print (struct derivation * derivation, FILE * stream)
 {
-  fprintf (stream, "At %x: ", (int) derivation);
+  fprintf (stream, "At %p: ", derivation);
   switch (derivation->type)
     {
     case nothing:
@@ -525,7 +525,7 @@ output_file (struct output * out, a2ps_job * job,
 		     expand_user_string (job, FIRST_FILE (job),
 					 (const uchar *) "Expand: requirement",
 					 (const uchar *) token));
-	output (dest, expansion);
+	output (dest, "%s", expansion);
 	continue;
       }
 
--- a/lib/parseppd.y
+++ b/lib/parseppd.y
@@ -154,7 +154,7 @@ font_clause :
 void
 yyerror (const char *msg)
 {
-  error_at_line (1, 0, ppdfilename, ppdlineno, msg);
+  error_at_line (1, 0, ppdfilename, ppdlineno, "%s", msg);
 }
 
 /*
--- a/lib/psgen.c
+++ b/lib/psgen.c
@@ -232,7 +232,7 @@ output_marker (a2ps_job * job, const char * kind, uchar * marker)
     default:
       *buf = '\0';
       ps_escape_char (job, cp[i], buf);
-      output (jdiv, (char *) buf);
+      output (jdiv, "%s", buf);
       break;
     }
   }
--- a/lib/quotearg.c
+++ b/lib/quotearg.c
@@ -60,6 +60,7 @@
 
 #if HAVE_MBRTOWC && HAVE_WCHAR_H
 # include <wchar.h>
+# include <wctype.h>
 #else
 # define iswprint(wc) 1
 # define mbrtowc(pwc, s, n, ps) 1
--- a/lib/title.c
+++ b/lib/title.c
@@ -28,6 +28,7 @@
 #endif
 
 #include <stdio.h>
+#include <string.h>
 
 #if HAVE_VPRINTF || HAVE_DOPRNT || _LIBC
 # if __STDC__
--- a/src/long-options.c
+++ b/src/long-options.c
@@ -22,6 +22,7 @@
 #endif
 
 #include <stdio.h>
+#include <stdlib.h>
 #include <getopt.h>
 #include "closeout.h"
 #include "long-options.h"
--- a/src/parsessh.y
+++ b/src/parsessh.y
@@ -740,7 +740,7 @@ exception_def_opt:
 void
 yyerror (const char *msg)
 {
-  error_at_line (1, 0, sshfilename, sshlineno, msg);
+  error_at_line (1, 0, sshfilename, sshlineno, "%s", msg);
 }
 
 /*