diff --git a/cde/lib/tt/bin/ttauth/ttauth.h b/cde/lib/tt/bin/ttauth/ttauth.h
index df6d58159..5e1b27f5f 100644
--- a/cde/lib/tt/bin/ttauth/ttauth.h
+++ b/cde/lib/tt/bin/ttauth/ttauth.h
@@ -57,7 +57,9 @@ typedef int Bool;
 
 extern char *ProgramName;
 
+#if !defined(linux)
 extern char *malloc(), *realloc();
+#endif
 int process_command(), auth_initialize(), auth_finalize();
 extern int print_help();
 extern int verbose;