diff --git a/wiring/wireOps.c b/wiring/wireOps.c
index bb80ae19..4b8fb249 100644
--- a/wiring/wireOps.c
+++ b/wiring/wireOps.c
@@ -19,7 +19,7 @@
  */
 
 #ifndef lint
-static char rcsid[] __attribute__ ((unused)) = "$Header$";
+static const char rcsid[] __attribute__ ((unused)) = "$Header$";
 #endif  /* not lint */
 
 #include <stdio.h>
diff --git a/wiring/wireTech.c b/wiring/wireTech.c
index 2dbe7cd2..bfa73b3d 100644
--- a/wiring/wireTech.c
+++ b/wiring/wireTech.c
@@ -18,7 +18,7 @@
  */
 
 #ifndef lint
-static char rcsid[] __attribute__ ((unused)) = "$Header$";
+static const char rcsid[] __attribute__ ((unused)) = "$Header$";
 #endif  /* not lint */
 
 #include <stdio.h>
diff --git a/wiring/wireUndo.c b/wiring/wireUndo.c
index e2e2b615..719a530e 100644
--- a/wiring/wireUndo.c
+++ b/wiring/wireUndo.c
@@ -18,7 +18,7 @@
  */
 
 #ifndef lint
-static char rcsid[] __attribute__ ((unused)) = "$Header$";
+static const char rcsid[] __attribute__ ((unused)) = "$Header$";
 #endif  /* not lint */
 
 #include <stdio.h>