diff --git a/PDP10/ka10_dpk.c b/PDP10/ka10_dpk.c
index d83994d..7eb0464 100644
--- a/PDP10/ka10_dpk.c
+++ b/PDP10/ka10_dpk.c
@@ -130,7 +130,6 @@ static void dpk_set_ospeed (int port, uint64 data)
 static t_stat dpk_devio(uint32 dev, uint64 *data)
 {
     static int scan = 0;
-    DEVICE *dptr = &dpk_dev;
     int port;
 
     switch(dev & 07) {
diff --git a/PDP10/ka10_imx.c b/PDP10/ka10_imx.c
index b4623b1..5590933 100644
--- a/PDP10/ka10_imx.c
+++ b/PDP10/ka10_imx.c
@@ -171,8 +171,6 @@ t_stat imx_reset (DEVICE *dptr)
 
 t_stat imx_devio(uint32 dev, uint64 *data)
 {
-    DEVICE *dptr = &imx_dev;
-
     switch(dev & 07) {
     case CONO|4:
         sim_debug(DEBUG_CONO, &imx_dev, "%06llo\n", *data);
diff --git a/PDP10/ka10_mty.c b/PDP10/ka10_mty.c
index dce7331..0adc225 100644
--- a/PDP10/ka10_mty.c
+++ b/PDP10/ka10_mty.c
@@ -100,7 +100,6 @@ DEVICE mty_dev = {
 
 static t_stat mty_devio(uint32 dev, uint64 *data)
 {
-    DEVICE *dptr = &mty_dev;
     TMLN *lp;
     int line;
     uint64 word;
diff --git a/PDP10/ka10_pclk.c b/PDP10/ka10_pclk.c
index 4a9b602..bcd56a3 100644
--- a/PDP10/ka10_pclk.c
+++ b/PDP10/ka10_pclk.c
@@ -70,7 +70,6 @@ DEVICE pclk_dev = {
 */
 t_stat pclk_devio(uint32 dev, uint64 *data)
 {
-    DEVICE *dptr = &pclk_dev;
     time_t t=time(NULL);
     struct tm *dt;
     uint64 hour=12, minute=1, seconds=2, milliseconds=3;
diff --git a/PDP10/ka10_pmp.c b/PDP10/ka10_pmp.c
index 95311c3..bed2724 100644
--- a/PDP10/ka10_pmp.c
+++ b/PDP10/ka10_pmp.c
@@ -968,7 +968,6 @@ pmp_startcmd() {
 void
 pmp_adjpos(UNIT * uptr)
 {
-    uint16              addr = GET_UADDR(uptr->flags);
     struct pmp_t      *data = (struct pmp_t *)(uptr->DATAPTR);
     uint8               *rec;
     int                 pos;
@@ -2138,7 +2137,6 @@ int
 pmp_format(UNIT * uptr, int flag) {
     struct pmp_header  hdr;
     struct pmp_t       *data;
-    uint16              addr = GET_UADDR(uptr->flags);
     int                 type = GET_TYPE(uptr->flags);
     int                 tsize;
     int                 cyl;
@@ -2295,7 +2293,6 @@ pmp_detach(UNIT * uptr)
 {
     struct pmp_t       *data = (struct pmp_t *)uptr->DATAPTR;
     int                 type = GET_TYPE(uptr->flags);
-    uint16              addr = GET_UADDR(uptr->flags);
     int                 cmd = uptr->CMD & 0x7f;
 
     if (uptr->CMD & DK_CYL_DIRTY) {
@@ -2403,7 +2400,6 @@ pmp_help (FILE *st, DEVICE *dptr, UNIT *uptr, int32 flag,
     fprintf (st, ".\nEach drive has the following storage capacity:\n\n");
     for (i = 0; disk_type[i].name != 0; i++) {
         int32 size = disk_type[i].bpt * disk_type[i].heads * disk_type[i].cyl;
-        char  sm = 'K';
         size /= 1024;
         size = (10 * size) / 1024;
         fprintf(st, "      %-8s %4d.%1dMB\n", disk_type[i].name, size/10, size%10);
diff --git a/PDP10/ka10_stk.c b/PDP10/ka10_stk.c
index 1297777..ae65340 100644
--- a/PDP10/ka10_stk.c
+++ b/PDP10/ka10_stk.c
@@ -359,8 +359,6 @@ static t_stat stk_svc (UNIT *uptr)
 
 t_stat stk_devio(uint32 dev, uint64 *data)
 {
-    DEVICE *dptr = &stk_dev;
-
     switch(dev & 07) {
     case CONO:
         status &= ~STK_PIA;
diff --git a/PDP10/ka10_tk10.c b/PDP10/ka10_tk10.c
index 9815c29..a9442f5 100644
--- a/PDP10/ka10_tk10.c
+++ b/PDP10/ka10_tk10.c
@@ -98,7 +98,6 @@ DEVICE tk10_dev = {
 
 static t_stat tk10_devio(uint32 dev, uint64 *data)
 {
-    DEVICE *dptr = &tk10_dev;
     TMLN *lp;
     int port;
     int ch;
diff --git a/PDP10/kl10_fe.c b/PDP10/kl10_fe.c
index ad97ccb..ffd92f2 100644
--- a/PDP10/kl10_fe.c
+++ b/PDP10/kl10_fe.c
@@ -1793,15 +1793,6 @@ t_stat dtei_svc (UNIT *uptr)
 /* Handle output of characters to CTY. Started whenever there is output pending */
 t_stat dteo_svc (UNIT *uptr)
 {
-    uint32   base = 0;
-    UNIT     *optr = &dte_unit[0];
-
-#if KI_22BIT
-#if KL_ITS
-    if (!QITS)
-#endif
-    base = eb_ptr;
-#endif
     /* Flush out any pending CTY output */
     while(not_empty(&cty_out)) {
         char ch = cty_out.buff[cty_out.out_ptr];
@@ -1972,7 +1963,7 @@ const char *dte_description (DEVICE *dptr)
 void
 lp20_printline(UNIT *uptr, int nl) {
     int     trim = 0;
-    uint16  data1 = 1;
+
     /* Trim off trailing blanks */
     while (uptr->COL >= 0 && lp20_buffer[uptr->COL - 1] == ' ') {
          uptr->COL--;
@@ -2027,7 +2018,6 @@ t_stat lp20_svc (UNIT *uptr)
     char    ch;
     uint16  ram_ch;
     uint16  data1[5];
-    int     l = uptr->LINE;
 
     if ((uptr->flags & UNIT_ATT) == 0)
         return SCPE_OK;
@@ -2055,7 +2045,7 @@ t_stat lp20_svc (UNIT *uptr)
     while (not_empty(&lp20_queue)) {
         ch = lp20_queue.buff[lp20_queue.out_ptr];
         inco(&lp20_queue);
-        ram_ch = lp20_ram[ch];
+        ram_ch = lp20_ram[(int)ch];
 
         /* If previous was delimiter or translation do it */
         if (uptr->LPST & DELFLG || (ram_ch &(LP20_RAM_DEL|LP20_RAM_TRN)) != 0) {
@@ -2283,7 +2273,6 @@ t_stat ttyo_svc (UNIT *uptr)
 {
     t_stat   r;
     int32    ln;
-    int      n = 0;
     TMLN     *lp;
 
     if ((tty_unit[0].flags & UNIT_ATT) == 0)                  /* attached? */
diff --git a/PDP10/kl10_nia.c b/PDP10/kl10_nia.c
index 734649a..2b778f0 100644
--- a/PDP10/kl10_nia.c
+++ b/PDP10/kl10_nia.c
@@ -713,9 +713,12 @@ uint8 *nia_cpy_from(t_addr addr, uint8 *data, int len)
         case 1:
                 word =  (uint64)(*data++) << 28;
                 break;
+        default:
+                word = 0;
+                break;
         }
+        M[addr++] = word;
     }
-    M[addr++] = word;
     return data;
 }
 
@@ -1200,7 +1203,6 @@ int nia_send_pkt(uint64 cmd)
  */
 t_stat nia_cmd_srv(UNIT * uptr)
 {
-    t_addr free_q = nia_data.unk_hdr;
     uint64    word1, word2;
     uint32    cmd;
     int       len, i;
diff --git a/PDP10/kx10_cpu.c b/PDP10/kx10_cpu.c
index 59b8881..a8ea32a 100644
--- a/PDP10/kx10_cpu.c
+++ b/PDP10/kx10_cpu.c
@@ -1275,8 +1275,6 @@ t_stat null_dev(uint32 dev, uint64 *data) {
 }
 
 #if KL
-static int      timer_irq, timer_flg;
-
 void
 update_times(int tim)
 {
@@ -2303,7 +2301,6 @@ pg_loop:
  */
 int page_lookup(t_addr addr, int flag, t_addr *loc, int wr, int cur_context, int fetch) {
     int      data;
-    int      base = 0;
     int      page = (RMASK & addr) >> 9;
     int      uf = (FLAGS & USER) != 0;
     int      pub = (FLAGS & PUBLIC) != 0;
@@ -2617,7 +2614,6 @@ int exec_page_lookup(t_addr addr, int wr, t_addr *loc)
 
 int Mem_examine_word(int n, int wrd, uint64 *data) {
     t_addr   addr = 0144 + (8 * n) + eb_ptr;
-    int      base = 0;
 
     if (addr >= MEMSIZE)
         return 1;
@@ -2632,7 +2628,6 @@ int Mem_examine_word(int n, int wrd, uint64 *data) {
 
 int Mem_deposit_word(int n, int wrd, uint64 *data) {
     t_addr   addr = 0146 + (8 * n) + eb_ptr;
-    int      base = 0;
 
     if (addr >= MEMSIZE)
         return 1;
@@ -2802,7 +2797,6 @@ load_tlb(int uf, int page)
  */
 int page_lookup(t_addr addr, int flag, t_addr *loc, int wr, int cur_context, int fetch) {
     int      data;
-    int      base = 0;
     int      page = (RMASK & addr) >> 9;
     int      uf = (FLAGS & USER) != 0;
     int      pub = (FLAGS & PUBLIC) != 0;
@@ -3027,7 +3021,6 @@ int its_load_tlb(uint32 reg, int page, uint32 *tlb) {
 
 int page_lookup_its(t_addr addr, int flag, t_addr *loc, int wr, int cur_context, int fetch) {
     uint64   data;
-    int      base = 0;
     int      page = (RMASK & addr) >> 10;
     int      acc;
     int      uf = (FLAGS & USER) != 0;
@@ -3281,7 +3274,6 @@ int page_lookup_bbn(t_addr addr, int flag, t_addr *loc, int wr, int cur_context,
     uint32   tlb_data;
     uint64   traps;
     int      base = 0;
-    int      trap = 0;
     int      lvl = 0;
     int      page = (RMASK & addr) >> 9;
     int      uf = (FLAGS & USER) != 0;
@@ -5385,6 +5377,7 @@ dpnorm:
               MQ = CCM(MB) + 1;   /* Low */
               /* High */
 #if KL
+              flag3 = 0;
               if ((CCM(AR) + ((MQ & SMASK) != 0)) & SMASK) {
                   FLAGS |= CRY1;
                   flag1 = 1;
@@ -5458,6 +5451,7 @@ dpnorm:
                   MQ = CCM(MQ) + 1;
                   if (MQ & SMASK) {
 #if KL
+                     flag1 = flag3 = 0;
                      if ((CCM(get_reg(AC)) + 1) & SMASK) {
                          FLAGS |= CRY1;
                          flag1 = 1;
@@ -9020,6 +9014,7 @@ do_byte_setup(int n, int wr, int *pos, int *sz)
                  ind = (MB & BIT1) != 0;
                  ix = (MB >> 30) & 017;
                  AB = MB & (SECTM|RMASK);
+                 temp = MB;
                  if (ix) {
                      temp = get_reg(ix);
                      if ((temp & SMASK) != 0 || (temp & SECTM) == 0) { /* Local index word */
@@ -9028,8 +9023,7 @@ do_byte_setup(int n, int wr, int *pos, int *sz)
                           temp = temp + AB;
                      temp &= FMASK;
                      MB = temp;
-                 } else
-                     temp = MB;
+                 }
                  sect = cur_sect = (temp >> 18) & 07777;
                  AB = temp & RMASK;
                  glb_sect = 1;
@@ -9372,28 +9366,28 @@ do_xlate(uint32 tbl, uint64 val, int mask)
 
 /* Table of powers of 10 for CVTBD opcodes */
 uint64 pow10_tab[22][2] = {
-     /*   0: */ 0000000000000LL, 0000000000001LL,
-     /*   1: */ 0000000000000LL, 0000000000012LL,
-     /*   2: */ 0000000000000LL, 0000000000144LL,
-     /*   3: */ 0000000000000LL, 0000000001750LL,
-     /*   4: */ 0000000000000LL, 0000000023420LL,
-     /*   5: */ 0000000000000LL, 0000000303240LL,
-     /*   6: */ 0000000000000LL, 0000003641100LL,
-     /*   7: */ 0000000000000LL, 0000046113200LL,
-     /*   8: */ 0000000000000LL, 0000575360400LL,
-     /*   9: */ 0000000000000LL, 0007346545000LL,
-     /*  10: */ 0000000000000LL, 0112402762000LL,
-     /*  11: */ 0000000000002LL, 0351035564000LL,
-     /*  12: */ 0000000000035LL, 0032451210000LL,
-     /*  13: */ 0000000000443LL, 0011634520000LL,
-     /*  14: */ 0000000005536LL, 0142036440000LL,
-     /*  15: */ 0000000070657LL, 0324461500000LL,
-     /*  16: */ 0000001070336LL, 0115760200000LL,
-     /*  17: */ 0000013064257LL, 0013542400000LL,
-     /*  18: */ 0000157013326LL, 0164731000000LL,
-     /*  19: */ 0002126162140LL, 0221172000000LL,
-     /*  20: */ 0025536165705LL, 0254304000000LL,
-     /*  21: */ 0330656232670LL, 0273650000000LL
+     /*   0: */ { 0000000000000LL, 0000000000001LL },
+     /*   1: */ { 0000000000000LL, 0000000000012LL },
+     /*   2: */ { 0000000000000LL, 0000000000144LL },
+     /*   3: */ { 0000000000000LL, 0000000001750LL },
+     /*   4: */ { 0000000000000LL, 0000000023420LL },
+     /*   5: */ { 0000000000000LL, 0000000303240LL },
+     /*   6: */ { 0000000000000LL, 0000003641100LL },
+     /*   7: */ { 0000000000000LL, 0000046113200LL },
+     /*   8: */ { 0000000000000LL, 0000575360400LL },
+     /*   9: */ { 0000000000000LL, 0007346545000LL },
+     /*  10: */ { 0000000000000LL, 0112402762000LL },
+     /*  11: */ { 0000000000002LL, 0351035564000LL },
+     /*  12: */ { 0000000000035LL, 0032451210000LL },
+     /*  13: */ { 0000000000443LL, 0011634520000LL },
+     /*  14: */ { 0000000005536LL, 0142036440000LL },
+     /*  15: */ { 0000000070657LL, 0324461500000LL },
+     /*  16: */ { 0000001070336LL, 0115760200000LL },
+     /*  17: */ { 0000013064257LL, 0013542400000LL },
+     /*  18: */ { 0000157013326LL, 0164731000000LL },
+     /*  19: */ { 0002126162140LL, 0221172000000LL },
+     /*  20: */ { 0025536165705LL, 0254304000000LL },
+     /*  21: */ { 0330656232670LL, 0273650000000LL }
 };
 
 /*
@@ -9784,9 +9778,10 @@ do_extend(uint32 ia)
     case 012:  /* CVTBDO */
     case 013:  /* CVTBDT */
               /* Save E1 */
-              if (IR == 012)
+              if (IR == 012) {
                   val2 = ((AR & RSIGN) ? LMASK : 0) | (AR & RMASK);
-              else {
+                  xlat_sect = cur_sect;
+              } else {
                   val2 = AB;
                   if (QKLB && pc_sect != 0 && glb_sect)
                      xlat_sect = (AR >> 18) & 07777;
@@ -9875,6 +9870,7 @@ do_extend(uint32 ia)
     case 015:  /* MOVST */
     case 016:  /* MOVSLJ */
               get_mask(ext_ac+3, &msk);
+              xlat_sect = cur_sect;
               if ((((get_reg(ext_ac) & (077LL << 26))| get_reg(ext_ac+3)) & EMASK) != 0)
                   return 1;
               if (IR == 014) {
@@ -10259,7 +10255,9 @@ t_bool build_dev_tab (void)
 DEVICE *dptr;
 DIB    *dibp;
 uint32 i, j, d;
+#if KL
 int     rh20;
+#endif
 int     rh_idx;
 
 /* Set trap offset based on MAOFF flag */
@@ -10316,7 +10314,9 @@ if (QBBN)
 
 
 /* Assign all RH10 & RH20  devices */
+#if KL
 rh20 = 0540;
+#endif
 rh_idx = 0;
 for (i = 0; (dptr = rh_devs[i]) != NULL; i++) {
     dibp = (DIB *) dptr->ctxt;
diff --git a/PDP10/kx10_dpy.c b/PDP10/kx10_dpy.c
index 668cda4..0f7ad56 100644
--- a/PDP10/kx10_dpy.c
+++ b/PDP10/kx10_dpy.c
@@ -341,7 +341,6 @@ static int joy_buttons[JOY_MAX_UNITS * JOY_MAX_BUTTONS];
 
 static void dpy_joy_motion(int which, int axis, int value)
 {
-  int result = FALSE;
   if (which < JOY_MAX_UNITS && axis < JOY_MAX_AXES) {
     joy_axes[which * JOY_MAX_AXES + axis] = value;
   }
@@ -349,7 +348,6 @@ static void dpy_joy_motion(int which, int axis, int value)
 
 static void dpy_joy_button(int which, int button, int state)
 {
-  int result = FALSE;
   if (which < JOY_MAX_UNITS && button < JOY_MAX_BUTTONS) {
     joy_buttons[which * JOY_MAX_UNITS + button] = state;
   }
diff --git a/PDP10/kx10_dt.c b/PDP10/kx10_dt.c
index 449e788..f92bf34 100644
--- a/PDP10/kx10_dt.c
+++ b/PDP10/kx10_dt.c
@@ -1062,7 +1062,7 @@ dt_boot(int32 unit_num, DEVICE * dptr)
 {
     UNIT               *uptr = &dptr->units[unit_num];
     uint32             *fbuf = (uint32 *) uptr->filebuf;    /* file buffer */
-    uint64              word;
+    uint64              word = 0;
     int                 off;
     int                 wc, addr;
 
@@ -1232,7 +1232,6 @@ void dt_flush (UNIT* uptr)
     uint16 pdp8b[D8_NBSIZE];
     uint16 pdp11b[D18_BSIZE];
     uint32 ba, k, *fbuf;
-    int32 u = uptr - dt_dev.units;
 
     if (uptr->WRITTEN && uptr->hwmark && ((uptr->flags & UNIT_RO) == 0)) {   /* any data? */
         rewind (uptr->fileref);                             /* start of file */
diff --git a/PDP10/kx10_imp.c b/PDP10/kx10_imp.c
index 4ebd6c1..289edba 100644
--- a/PDP10/kx10_imp.c
+++ b/PDP10/kx10_imp.c
@@ -743,7 +743,6 @@ imp_devirq(uint32 dev, t_addr addr) {
 
 t_stat imp_srv(UNIT * uptr)
 {
-    DEVICE *dptr = find_dev_from_unit(uptr);
     int     i;
     int     l;
 
@@ -1017,7 +1016,6 @@ imp_packet_in(struct imp_device *imp)
            if (ip_hdr->ip_dst == imp_data.ip && imp_data.hostip != 0) {
                uint8   *payload = (uint8 *)(&imp->rbuffer[pad +
                                            (ip_hdr->ip_v_hl & 0xf) * 4]);
-               uint16   chk = ip_hdr->ip_sum;
                /* If TCP packet update the TCP checksum */
                if (ip_hdr->ip_p == TCP_PROTO) {
                    struct tcp *tcp_hdr = (struct tcp *)payload;
diff --git a/PDP10/kx10_rh.c b/PDP10/kx10_rh.c
index c2e5d72..80d409c 100644
--- a/PDP10/kx10_rh.c
+++ b/PDP10/kx10_rh.c
@@ -491,7 +491,6 @@ t_stat rh_devio(uint32 dev, uint64 *data) {
 /* Handle KI and KL style interrupt vectors */
 t_addr
 rh_devirq(uint32 dev, t_addr addr) {
-    DEVICE        *dptr = NULL;
     struct rh_if  *rhc = NULL;
     int            drive;
 
diff --git a/PDP10/kx10_sys.c b/PDP10/kx10_sys.c
index 04b1609..cedb331 100644
--- a/PDP10/kx10_sys.c
+++ b/PDP10/kx10_sys.c
@@ -774,6 +774,7 @@ t_stat load_exb (FILE *fileref, int ftype)
             return SCPE_OK;
         }
         pos = 0;
+        word = 0;
         for (; wc > 0; wc--, pos++) {
             if (get_exb_byte(fileref, &byt, ftype))
                 return SCPE_FMT;
@@ -1124,11 +1125,10 @@ static const char *devnam[NUMDEV] = {
 t_stat fprint_sym (FILE *of, t_addr addr, t_value *val,
     UNIT *uptr, int32 sw)
 {
-int32 i, j, c, cflag, ac, xr, y, dev;
+int32 i, j, c, ac, xr, y, dev;
 uint64 inst;
 
 inst = val[0];
-cflag = (uptr == NULL) || (uptr == &cpu_unit[0]);
 if (sw & SWMASK ('A')) {                                /* ASCII? */
     if (inst > 0377)
         return SCPE_ARG;
@@ -1250,12 +1250,11 @@ return (ind | (xr << 18) | val);
 
 t_stat parse_sym (CONST char *cptr, t_addr addr, UNIT *uptr, t_value *val, int32 sw)
 {
-int32 cflag, i, j;
+int32 i, j;
 t_value ac, dev;
 t_stat r;
 char gbuf[CBUFSIZE], cbuf[2*CBUFSIZE];
 
-cflag = (uptr == NULL) || (uptr == &cpu_unit[0]);
 while (isspace (*cptr)) cptr++;
 memset (cbuf, '\0', sizeof(cbuf));
 strncpy (cbuf, cptr, sizeof(cbuf)-7);
diff --git a/PDP10/pdp6_dtc.c b/PDP10/pdp6_dtc.c
index c4e1567..447b92e 100644
--- a/PDP10/pdp6_dtc.c
+++ b/PDP10/pdp6_dtc.c
@@ -1072,7 +1072,7 @@ dtc_boot(int32 unit_num, DEVICE * dptr)
 {
     UNIT               *uptr = &dptr->units[unit_num];
     uint32             *fbuf = (uint32 *) uptr->filebuf;    /* file buffer */
-    uint64              word;
+    uint64              word = 0;
     int                 off;
     int                 wc, addr;