diff --git a/clients/lcdproc/util.c b/clients/lcdproc/util.c
index 4ee34fb..5e23bc8 100644
--- a/clients/lcdproc/util.c
+++ b/clients/lcdproc/util.c
@@ -42,7 +42,7 @@ sprintf_memory(char *dst, double value, double roundlimit)
 		if ((roundlimit <= 0.0) || (roundlimit > 1.0))
 			roundlimit = 0.5;
 
-		while (units[offs] != NULL > 0) {
+		while (units[offs] != NULL) {
 			if (value <= 1024 * roundlimit)
 				break;
 			offs++;
diff --git a/server/drivers/CFontz633.c b/server/drivers/CFontz633.c
index 28631ba..5c0d351 100644
--- a/server/drivers/CFontz633.c
+++ b/server/drivers/CFontz633.c
@@ -442,7 +442,7 @@ CFontz633_flush (Driver *drvthis)
 MODULE_EXPORT char *
 CFontz633_get_key (Driver *drvthis)
 {
-	PrivateData *p = drvthis->private_data;
+	// PrivateData *p = drvthis->private_data;
 	unsigned char key;
 
 	key = GetKeyFromKeyRing(&keyring);
diff --git a/server/drivers/MtxOrb.c b/server/drivers/MtxOrb.c
index d02738a..48d4297 100644
--- a/server/drivers/MtxOrb.c
+++ b/server/drivers/MtxOrb.c
@@ -469,7 +469,7 @@ MtxOrb_init (Driver *drvthis)
 
 	/* Make sure the frame buffer is there... */
 	if (!p->framebuf)
-		p->framebuf = (unsigned char *)
+		p->framebuf = (char *)
 			malloc (p->widthBYheight);
 	memset (p->framebuf, ' ', p->widthBYheight);
 
diff --git a/server/drivers/curses_drv.c b/server/drivers/curses_drv.c
index 293a648..0dfa0c1 100644
--- a/server/drivers/curses_drv.c
+++ b/server/drivers/curses_drv.c
@@ -399,13 +399,12 @@ curses_drv_backlight (Driver *drvthis, int promille)
 MODULE_EXPORT void
 curses_drv_string (Driver *drvthis, int x, int y, char *string)
 {
-	//int i;
 	unsigned char *p;
 
 	ValidX(x);
 	ValidY(y);
 
-	p = string;
+	p = (unsigned char *) string;
 
 	// Convert NULLs and 0xFF in string to
 	// valid printables...
diff --git a/server/drivers/glk.c b/server/drivers/glk.c
index 4633421..5e15c3c 100644
--- a/server/drivers/glk.c
+++ b/server/drivers/glk.c
@@ -50,7 +50,7 @@ static unsigned char *  screen_contents = NULL ;
 static int  fontselected = 0 ;
 static int  gpo_count = 0 ;
 
-static char *framebuf = NULL;
+static unsigned char * framebuf = NULL;
 static int width = 0;
 static int height = 0;
 static int cellwidth = LCD_DEFAULT_CELLWIDTH;
@@ -241,11 +241,11 @@ MODULE_EXPORT void
 glk_flush(Driver *drvthis)
 {
 //   puts( "glk_flush( )" );
-  char *  p ;
-  char *  q ;
+  unsigned char *  p ;
+  unsigned char *  q ;
   int  x, y ;
   int  xs ;
-  char *  ps = NULL ;
+  unsigned char *  ps = NULL ;
 
   debug(RPT_DEBUG, "flush()\n" );
 
diff --git a/server/drivers/lb216.c b/server/drivers/lb216.c
index 85e7cb7..f0aeb2b 100644
--- a/server/drivers/lb216.c
+++ b/server/drivers/lb216.c
@@ -146,7 +146,7 @@ LB216_init(Driver * drvthis)
    tcsetattr(fd, TCSANOW, &portset);
 
    // Make sure the frame buffer is there...
-   framebuf = (unsigned char *) malloc (width * height);
+   framebuf = malloc (width * height);
    if (framebuf == NULL) {
       report(RPT_ERR, "lb216_init: unable to create framebuffer.\n");
       return -1;
diff --git a/server/drivers/text.c b/server/drivers/text.c
index a54aef9..27a067f 100644
--- a/server/drivers/text.c
+++ b/server/drivers/text.c
@@ -78,7 +78,7 @@ text_init (Driver *drvthis)
 	}
 
 	// Allocate the framebuffer
-	framebuf = (unsigned char *) malloc (width * height);
+	framebuf = malloc (width * height);
 	memset (framebuf, ' ', width * height);
 
 	return 0;
diff --git a/shared/snprintf.c b/shared/snprintf.c
index 2fb4411..d771bc8 100644
--- a/shared/snprintf.c
+++ b/shared/snprintf.c
@@ -415,6 +415,8 @@ static char credits[] = "\n\
 @(#)snprintf.c, v2.2: Mark Martinec, <mark.martinec@ijs.si>\n\
 @(#)snprintf.c, v2.2: Copyright 1999, Mark Martinec. Frontier Artistic License applies.\n\
 @(#)snprintf.c, v2.2: http://www.ijs.si/software/snprintf/\n";
+/* avoid not used warning */
+inline const char* get_credits_snprintf(const char* dummy) { return credits; }
 
 #if defined(NEED_ASPRINTF)
 int asprintf(char **ptr, const char *fmt, /*args*/ ...) {