diff --git a/cpukit/libcsupport/src/issetugid.c b/cpukit/libcsupport/src/issetugid.c
index 0cb870ea00..8d2b98cad1 100644
--- a/cpukit/libcsupport/src/issetugid.c
+++ b/cpukit/libcsupport/src/issetugid.c
@@ -12,6 +12,11 @@
 
 #if defined(RTEMS_NEWLIB) && !defined(HAVE_ISSETUGID)
 
+/*
+ *  Prototype to avoid warnings
+ */
+int issetugid (void);
+
 /**
  *  Dummy version of BSD routine
  */