3 files changed, 3 insertions, 3 deletions
diff --git a/progs/redbook/tess.c b/progs/redbook/tess.c
index bf3409eac7..238a469aff 100644
--- a/progs/redbook/tess.c
+++ b/progs/redbook/tess.c
@@ -79,7 +79,7 @@ void CALLBACK errorCallback(GLenum errorCode)
    const GLubyte *estring;
 
    estring = gluErrorString(errorCode);
-   fprintf(stderr, "Tessellation Error: %s\n", estring);
+   fprintf(stderr, "Tessellation Error: %s\n", (char *) estring);
    exit(0);
 }
 
diff --git a/progs/redbook/tesswind.c b/progs/redbook/tesswind.c
index 86639d4882..7d00c9f907 100644
--- a/progs/redbook/tesswind.c
+++ b/progs/redbook/tesswind.c
@@ -178,7 +178,7 @@ void CALLBACK errorCallback(GLenum errorCode)
    const GLubyte *estring;
 
    estring = gluErrorString(errorCode);
-   fprintf(stderr, "Tessellation Error: %s\n", estring);
+   fprintf(stderr, "Tessellation Error: %s\n", (char *) estring);
    exit(0);
 }
 
diff --git a/progs/redbook/trim.c b/progs/redbook/trim.c
index 26f474814c..f17674f684 100644
--- a/progs/redbook/trim.c
+++ b/progs/redbook/trim.c
@@ -80,7 +80,7 @@ void nurbsError(GLenum errorCode)
    const GLubyte *estring;
 
    estring = gluErrorString(errorCode);
-   fprintf (stderr, "Nurbs Error: %s\n", estring);
+   fprintf (stderr, "Nurbs Error: %s\n", (char *) estring);
    exit (0);
 }