diff --git a/PDP10/pdp10_rp.c b/PDP10/pdp10_rp.c
index b26d04f4..176c5bc3 100644
--- a/PDP10/pdp10_rp.c
+++ b/PDP10/pdp10_rp.c
@@ -1192,8 +1192,6 @@ return sim_disk_detach (uptr);
 
 t_stat rp_set_type (UNIT *uptr, int32 val, CONST char *cptr, void *desc)
 {
-int32 dtype = GET_DTYPE (val);
-
 if ((val < 0) || (cptr && *cptr))
     return SCPE_ARG;
 if (uptr->flags & UNIT_ATT)
diff --git a/VAX/vax4xx_rz80.c b/VAX/vax4xx_rz80.c
index 1ddc49f6..46669e72 100644
--- a/VAX/vax4xx_rz80.c
+++ b/VAX/vax4xx_rz80.c
@@ -329,7 +329,6 @@ int32 rz_rd (int32 pa)
 int32 ctlr = (pa >> 8) & 1;
 CTLR *rz = rz_ctxmap[ctlr];
 DEVICE *dptr = rz_devmap[ctlr];
-UNIT *uptr = dptr->units + RZ_CTLR;
 int32 rg = (pa >> 2) & 0x1F;
 int32 data = 0;
 int32 len;
diff --git a/VAX/vax_gpx.c b/VAX/vax_gpx.c
index 02dfd129..851ca192 100644
--- a/VAX/vax_gpx.c
+++ b/VAX/vax_gpx.c
@@ -188,8 +188,6 @@ void va_erase (uint32 x0, uint32 x1, uint32 y0, uint32 y1);
 
 void va_adpstat (uint32 set, uint32 clr)
 {
-uint32 chg = (va_adp[ADP_STAT] ^ set) & set;
-
 if (va_adp[ADP_INT] & set)                              /* unmasked ints 0->1? */
     va_setint (INT_ADP);
 va_adp[ADP_STAT] = va_adp[ADP_STAT] | set;
diff --git a/sim_ether.c b/sim_ether.c
index f9c78686..78488767 100644
--- a/sim_ether.c
+++ b/sim_ether.c
@@ -751,12 +751,12 @@ void eth_zero(ETH_DEV* dev)
   dev->reflections = -1;                          /* not established yet */
 }
 
-static char*   (*p_pcap_lib_version) (void);
-
 static ETH_DEV **eth_open_devices = NULL;
 static int eth_open_device_count = 0;
 
 #if defined (USE_NETWORK) || defined (USE_SHARED)
+static char*   (*p_pcap_lib_version) (void);
+
 static void _eth_add_to_open_list (ETH_DEV* dev)
 {
 eth_open_devices = (ETH_DEV**)realloc(eth_open_devices, (eth_open_device_count+1)*sizeof(*eth_open_devices));
diff --git a/sim_video.c b/sim_video.c
index d7f4fd71..f4ed5803 100644
--- a/sim_video.c
+++ b/sim_video.c
@@ -40,7 +40,6 @@ static VID_QUIT_CALLBACK vid_quit_callback = NULL;
 static VID_GAMEPAD_CALLBACK motion_callback[10];
 static VID_GAMEPAD_CALLBACK button_callback[10];
 static int vid_gamepad_inited = 0;
-static int vid_gamepad_ok = 0; /* Or else just joysticks. */
 
 t_stat vid_register_quit_callback (VID_QUIT_CALLBACK callback)
 {
@@ -95,6 +94,8 @@ return dev ? sim_dname(dev) : "Video Device";
 
 #if defined(USE_SIM_VIDEO) && defined(HAVE_LIBSDL)
 
+static int vid_gamepad_ok = 0; /* Or else just joysticks. */
+
 char vid_release_key[64] = "Ctrl-Right-Shift";
 
 #include <SDL.h>
@@ -610,7 +611,6 @@ if (0 == (--vid_gamepad_inited)) {
 
 static t_stat vid_init_window (VID_DISPLAY *vptr, DEVICE *dptr, const char *title, uint32 width, uint32 height, int flags)
 {
-int wait_count = 0;
 t_stat stat;
 
 if ((strlen(sim_name) + 7 + (dptr ? strlen (dptr->name) : 0) + (title ? strlen (title) : 0)) < sizeof (vptr->vid_title))
@@ -2446,7 +2446,6 @@ static int vid_beep_samples;
 
 static void vid_audio_callback(void *ctx, Uint8 *stream, int length)
 {
-int16 *data = (int16 *)stream;
 int i, sum, remnant = ((vid_beep_samples - vid_beep_offset) * sizeof (*vid_beep_data));
 
 if (length > remnant) {