diff --git a/include/commdef.h b/include/commdef.h
index a15433b..463fa4c 100644
--- a/include/commdef.h
+++ b/include/commdef.h
@@ -35,6 +35,7 @@
 #endif
 
 #include "cvar.h"
+#include "gcc_attr.h"
 
 /* The host system specifies the base of the directory tree, the
    command line parms passed to the program, and the amount of memory
@@ -61,7 +62,7 @@ extern	qboolean	host_initialized;	/* True if into command execution. */
 extern	double		realtime;			/* Not bounded in any way, changed at
 										   start of every frame, never reset */
 
-char	*va(char *format, ...);
+char	*va(char *format, ...) __attribute__((format(printf,1,2)));
 // does a varargs printf into a temp buffer
 
 #endif // _COMMDEF_H
diff --git a/include/console.h b/include/console.h
index b7ca799..692358d 100644
--- a/include/console.h
+++ b/include/console.h
@@ -33,6 +33,7 @@
 //
 
 #include "qtypes.h"
+#include "gcc_attr.h"
 
 #define		CON_TEXTSIZE	16384
 typedef struct
@@ -61,9 +62,9 @@ void Con_CheckResize (void);
 void Con_Init (void);
 void Con_DrawConsole (int lines);
 void Con_Print (char *txt);
-void Con_Printf (char *fmt, ...);
-void Con_DPrintf (char *fmt, ...);
-void Con_SafePrintf (char *fmt, ...);
+void Con_Printf (char *fmt, ...) __attribute__((format(printf,1,2)));
+void Con_DPrintf (char *fmt, ...) __attribute__((format(printf,1,2)));
+void Con_SafePrintf (char *fmt, ...) __attribute__((format(printf,1,2)));
 void Con_Clear_f (void);
 void Con_DrawNotify (void);
 void Con_ClearNotify (void);
diff --git a/include/gcc_attr.h b/include/gcc_attr.h
new file mode 100644
index 0000000..1819920
--- /dev/null
+++ b/include/gcc_attr.h
@@ -0,0 +1,36 @@
+/*
+	gcc_attr.h
+
+	GCC __attribute__ protection for lame compilers.
+
+	Copyright (C) 1996-1997  Id Software, Inc.
+
+	This program is free software; you can redistribute it and/or
+	modify it under the terms of the GNU General Public License
+	as published by the Free Software Foundation; either version 2
+	of the License, or (at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+	See the GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to:
+
+		Free Software Foundation, Inc.
+		59 Temple Place - Suite 330
+		Boston, MA  02111-1307, USA
+
+	$Id$
+*/
+
+#ifndef _GCC_ATTR_H
+#define _GCC_ATTR_H
+
+#ifndef __GNUC__
+#define __attribute__(x)
+#endif
+
+#endif	// _GCC_ATTR_H
diff --git a/include/net.h b/include/net.h
index c567cb8..dfd2c1e 100644
--- a/include/net.h
+++ b/include/net.h
@@ -29,6 +29,7 @@
 #ifndef _NET_H
 #define _NET_H
 
+#include "gcc_attr.h"
 #include "sizebuf.h"
 #include "cvar.h"
 
@@ -116,7 +117,7 @@ extern	int	net_drop;		// packets dropped before this one
 void Netchan_Init (void);
 void Netchan_Transmit (netchan_t *chan, int length, byte *data);
 void Netchan_OutOfBand (netadr_t adr, int length, byte *data);
-void Netchan_OutOfBandPrint (netadr_t adr, char *format, ...);
+void Netchan_OutOfBandPrint (netadr_t adr, char *format, ...) __attribute__((format(printf,2,3)));
 qboolean Netchan_Process (netchan_t *chan);
 void Netchan_Setup (netchan_t *chan, netadr_t adr, int qport);
 
diff --git a/include/progs.h b/include/progs.h
index d4c2311..8f7b342 100644
--- a/include/progs.h
+++ b/include/progs.h
@@ -29,6 +29,7 @@
 #ifndef _PROGS_H
 #define _PROGS_H
 
+#include "gcc_attr.h"
 #include "protocol.h"
 #include "pr_comp.h"			// defs shared with qcc
 #include "progdefs.h"			// generated by program cdefs
@@ -140,7 +141,7 @@ extern func_t SpectatorConnect;
 extern func_t SpectatorThink;
 extern func_t SpectatorDisconnect;
 
-void PR_RunError (char *error, ...);
+void PR_RunError (char *error, ...) __attribute__((format(printf,1,2)));
 
 void ED_PrintEdicts (void);
 void ED_PrintNum (int ent);
diff --git a/include/quakedef.h b/include/quakedef.h
index 3cf4243..1f621f7 100644
--- a/include/quakedef.h
+++ b/include/quakedef.h
@@ -29,6 +29,8 @@
 #ifndef _QUAKEDEF_H
 #define _QUAKEDEF_H
 
+#include "gcc_attr.h"
+
 #define	QUAKE_GAME			// as opposed to utilities
 
 //define	PARANOID			// speed sapping error checking
@@ -71,12 +73,12 @@ void Host_ServerFrame (void);
 void Host_InitCommands (void);
 void Host_Init (quakeparms_t *parms);
 void Host_Shutdown(void);
-void Host_Error (char *error, ...);
-void Host_EndGame (char *message, ...);
+void Host_Error (char *error, ...) __attribute__((format(printf,1,2)));
+void Host_EndGame (char *message, ...) __attribute__((format(printf,1,2)));
 qboolean Host_SimulationTime(float time);
 void Host_Frame (float time);
 void Host_Quit_f (void);
-void Host_ClientCommands (char *fmt, ...);
+void Host_ClientCommands (char *fmt, ...) __attribute__((format(printf,1,2)));
 void Host_ShutdownServer (qboolean crash);
 
 #endif // _QUAKEDEH_H
diff --git a/include/quakeio.h b/include/quakeio.h
index 3db19d6..9004de7 100644
--- a/include/quakeio.h
+++ b/include/quakeio.h
@@ -30,6 +30,7 @@
 #ifndef _QUAKEIO_H
 #define _QUAKEIO_H
 
+#include "gcc_attr.h"
 #include <stdio.h>
 
 #include <config.h>
@@ -41,7 +42,7 @@ FILE *Qdopen(int fd, const char *mode);
 void Qclose(FILE *file);
 int Qread(FILE *file, void *buf, int count);
 int Qwrite(FILE *file, void *buf, int count);
-int Qprintf(FILE *file, const char *fmt, ...);
+int Qprintf(FILE *file, const char *fmt, ...) __attribute__((format(printf,2,3)));
 char *Qgets(FILE *file, char *buf, int count);
 int Qgetc(FILE *file);
 int Qputc(FILE *file, int c);
diff --git a/include/server.h b/include/server.h
index 3120718..7f0f31f 100644
--- a/include/server.h
+++ b/include/server.h
@@ -30,6 +30,7 @@
 #ifndef _SERVER_H
 #define _SERVER_H
 
+#include "gcc_attr.h"
 #include "commdef.h"
 #include "net.h"
 #include "cvar.h"
@@ -369,11 +370,11 @@ extern	double		sv_frametime;
 //===========================================================
 // FIXME: declare exported functions in their own relevant .h
 
-void SV_Error (char *error, ...);
+void SV_Error (char *error, ...) __attribute__((format(printf,1,2)));
 void SV_Init (quakeparms_t *parms);
 
-void Con_Printf (char *fmt, ...);
-void Con_DPrintf (char *fmt, ...);
+void Con_Printf (char *fmt, ...) __attribute__((format(printf,1,2)));
+void Con_DPrintf (char *fmt, ...) __attribute__((format(printf,1,2)));
 
 //
 // sv_main.c
@@ -436,9 +437,9 @@ void SV_SendClientMessages (void);
 void SV_Multicast (vec3_t origin, int to);
 void SV_StartSound (edict_t *entity, int channel, char *sample, int volume,
     float attenuation);
-void SV_ClientPrintf (client_t *cl, int level, char *fmt, ...);
-void SV_BroadcastPrintf (int level, char *fmt, ...);
-void SV_BroadcastCommand (char *fmt, ...);
+void SV_ClientPrintf (client_t *cl, int level, char *fmt, ...) __attribute__((format(printf,3,4)));
+void SV_BroadcastPrintf (int level, char *fmt, ...) __attribute__((format(printf,2,3)));
+void SV_BroadcastCommand (char *fmt, ...) __attribute__((format(printf,1,2)));
 void SV_SendMessagesToAll (void);
 void SV_FindModelNumbers (void);
 
diff --git a/include/sys.h b/include/sys.h
index 6ab608e..9bd2eec 100644
--- a/include/sys.h
+++ b/include/sys.h
@@ -29,6 +29,8 @@
 #ifndef _SYS_H
 #define _SYS_H
 
+#include "gcc_attr.h"
+
 //
 // file IO
 //
@@ -54,12 +56,12 @@ void Sys_MakeCodeWriteable (unsigned long startaddr, unsigned long length);
 //
 // system IO
 //
-void Sys_DebugLog(char *file, char *fmt, ...);
+void Sys_DebugLog(char *file, char *fmt, ...) __attribute__((format(printf,2,3)));
 
-void Sys_Error (char *error, ...);
+void Sys_Error (char *error, ...) __attribute__((format(printf,1,2)));
 // an error will cause the entire program to exit
 
-void Sys_Printf (char *fmt, ...);
+void Sys_Printf (char *fmt, ...) __attribute__((format(printf,1,2)));
 // send text to the console
 
 void Sys_Quit (void);
@@ -76,7 +78,7 @@ void Sys_LowFPPrecision (void);
 void Sys_HighFPPrecision (void);
 void Sys_SetFPCW (void);
 
-void Sys_Printf (char *fmt, ...);
+void Sys_Printf (char *fmt, ...) __attribute__((format(printf,1,2)));
 // send text to the console
 
 void Sys_Init (void);
diff --git a/source/cl_parse.c b/source/cl_parse.c
index db0544d..83cd4eb 100644
--- a/source/cl_parse.c
+++ b/source/cl_parse.c
@@ -1258,13 +1258,13 @@ void CL_ParseServerMessage (void)
 			for (i=0 ; i<3 ; i++)
 			{
 				cl.simorg[i] = MSG_ReadCoord ();
-				Con_DPrintf ("%i ", cl.simorg[i]);
+				Con_DPrintf ("%f ", cl.simorg[i]);
 			}
 			Con_DPrintf ("\nintermission simangles: ");
 			for (i=0 ; i<3 ; i++)
 			{
 				cl.simangles[i] = MSG_ReadAngle ();
-				Con_DPrintf ("%i ", cl.simangles[i]);
+				Con_DPrintf ("%f ", cl.simangles[i]);
 			}
 			Con_DPrintf ("\n");
 			VectorCopy (vec3_origin, cl.simvel);
diff --git a/source/vid_x11.c b/source/vid_x11.c
index 670a5e9..02a46fb 100644
--- a/source/vid_x11.c
+++ b/source/vid_x11.c
@@ -557,7 +557,7 @@ void VID_Init (unsigned char *palette)
 			printf("	-visualid %d\n", (int)(x_visinfo[i].visualid));
 	} else if (num_visuals == 0) {
 		if (template_mask == VisualIDMask) {
-			Sys_Error("VID: Bad visual id %d\n",
+			Sys_Error("VID: Bad visual id %ld\n",
 				  template.visualid);
 		} else {
 			Sys_Error("VID: No visuals at depth %d\n",