diff --git a/bitbtest.c b/bitbtest.c
index 6bc6307..b65d743 100644
--- a/bitbtest.c
+++ b/bitbtest.c
@@ -221,9 +221,9 @@ static const unsigned int high_flip[56] = {
 #endif
 
 #define bbFlips_Right_high(pos, mask)	\
-  contig = right_contiguous[(opp_bits_high >> (pos + 1)) & mask];	\
-  fl = right_flip[contig] << (pos + 1);					\
-  t = -(int)(my_bits_high & fl) >> 31;					\
+  contig = right_contiguous[(opp_bits_high >> (pos + 1u)) & mask];	\
+  fl = right_flip[contig] << (pos + 1u);					\
+  t = ((int)(-(unsigned int)(my_bits_high & fl))) >> 31u;					\
   my_bits_high |= fl & t;						\
   flipped = contig & t
 
@@ -544,22 +544,22 @@ static const unsigned int high_flip[56] = {
 
 
 #define bbFlips_Down_2_3(pos, vec, maskh)	\
-  if (opp_bits_low & (1 << (pos + vec))) {				\
-    if (opp_bits_low & (1 << (pos + vec * 2))) {			\
-      t = (opp_bits_high >> (pos + vec * 3 - 32)) & 1;			\
-      contig = 2 + t;							\
-      t &= (opp_bits_high >> (pos + vec * 4 - 32));			\
+  if (opp_bits_low & (1u << (pos + vec))) {				\
+    if (opp_bits_low & (1u << (pos + vec * 2u))) {			\
+      t = (opp_bits_high >> (pos + vec * 3u - 32u)) & 1u;			\
+      contig = 2u + t;							\
+      t &= (opp_bits_high >> (pos + vec * 4u - 32u));			\
       contig += t;							\
-      t &= (opp_bits_high >> (pos + vec * 5 - 32));			\
+      t &= (opp_bits_high >> (pos + vec * 5u - 32u));			\
       contig += t;							\
       t = lsb_mask[contig - 2] & maskh;					\
       if (my_bits_high & t) {						\
         my_bits_high |= t;						\
-        my_bits_low |= (1 << (pos + vec)) | (1 << (pos + vec * 2));	\
+        my_bits_low |= (1u << (pos + vec)) | (1u << (pos + vec * 2u));	\
         flipped += contig;						\
       }									\
     } else {								\
-      t = (my_bits_low >> (pos + vec * 2)) & 1;				\
+      t = (my_bits_low >> (pos + vec * 2u)) & 1u;				\
       my_bits_low |= t << (pos + vec);					\
       flipped += t;							\
     }									\
@@ -679,17 +679,17 @@ static const unsigned int high_flip[56] = {
 
 
 #define bbFlips_Down_1_3(pos, vec, maskh)	\
-  if (opp_bits_low & (1 << (pos + vec))) {				\
-    t = (opp_bits_high >> (pos + vec * 2 - 32)) & 1;			\
+  if (opp_bits_low & (1u << (pos + vec))) {				\
+    t = (opp_bits_high >> (pos + vec * 2u - 32u)) & 1u;			\
     contig = 1 + t;							\
-    t &= (opp_bits_high >> (pos + vec * 3 - 32));			\
+    t &= (opp_bits_high >> (pos + vec * 3u - 32u));			\
     contig += t;							\
-    t &= (opp_bits_high >> (pos + vec * 4 - 32));			\
+    t &= (opp_bits_high >> (pos + vec * 4u - 32u));			\
     contig += t;							\
-    t = lsb_mask[contig - 1] & maskh;					\
+    t = lsb_mask[contig - 1u] & maskh;					\
     if (my_bits_high & t) {						\
       my_bits_high |= t;						\
-      my_bits_low |= 1 << (pos + vec);					\
+      my_bits_low |= 1u << (pos + vec);					\
       flipped += contig;						\
     }									\
   }
@@ -795,10 +795,10 @@ static const unsigned int high_flip[56] = {
 #endif
 
 #define bbFlips_Up_0_3(pos, vec, mask)	\
-  if (opp_bits_low & (1 << (pos + 32 - vec))) {				\
-    t = (opp_bits_low >> (pos + 32 - vec * 2)) & 1;			\
+  if (opp_bits_low & (1u << (pos + 32u - vec))) {				\
+    t = (opp_bits_low >> (pos + 32u - vec * 2u)) & 1u;			\
     contig = 1 + t;							\
-    t &= (opp_bits_low >> (pos + 32 - vec * 3));			\
+    t &= (opp_bits_low >> (pos + 32u - vec * 3u));			\
     contig += t;							\
     fl = msb_mask[contig] & mask;					\
     t = -(int)(my_bits_low & fl) >> 31;					\
@@ -1021,7 +1021,7 @@ TestFlips_bitboard_a8( unsigned int my_bits_high, unsigned int my_bits_low, unsi
   unsigned int t, fl;
 
   /* Right */
-  bbFlips_Right_high(24, 0x3F);
+  bbFlips_Right_high(24u, 0x3Fu);
   /* Up right */
   bbFlips_Up_3_3(24, 7, 0x00020408u, 0x10204080u);
   /* Up */
@@ -1115,7 +1115,7 @@ TestFlips_bitboard_h2( unsigned int my_bits_high, unsigned int my_bits_low, unsi
   /* Down left */
   bbFlips_Down_2_3(15, 7, 0x02040810u);
   /* Down */
-  bbFlips_Down_2_3(15, 8, 0x80808080u);
+  bbFlips_Down_2_3(15u, 8u, 0x80808080u);
 
   my_bits_low |= 0x00008000u;
   bb_flips.high = my_bits_high;
@@ -1339,7 +1339,7 @@ TestFlips_bitboard_h3( unsigned int my_bits_high, unsigned int my_bits_low, unsi
   /* Down left */
   bbFlips_Down_1_3(23, 7, 0x04081020u);
   /* Down */
-  bbFlips_Down_1_3(23, 8, 0x80808080u);
+  bbFlips_Down_1_3(23u, 8u, 0x80808080u);
   /* Up */
   bbFlips_Up_1_low(23, 8);
   /* Up left */
@@ -1553,7 +1553,7 @@ TestFlips_bitboard_h5( unsigned int my_bits_high, unsigned int my_bits_low, unsi
   /* Down */
   bbFlips_Down_2_high(7, 8, 0x00808000u);
   /* Up */
-  bbFlips_Up_0_3(7, 8, 0x80808080u);
+  bbFlips_Up_0_3(7u, 8u, 0x80808080u);
   /* Up left */
   bbFlips_Up_0_3(7, 9, 0x40201008u);
 
diff --git a/end.c b/end.c
index cdc92bc..fc23ccf 100644
--- a/end.c
+++ b/end.c
@@ -2409,7 +2409,7 @@ setup_end( void ) {
 	if ( dir_mask[pos] & (1 << k) ) {
 	  unsigned int neighbor = shift + dir_shift[k];
 	  if ( neighbor < 32 )
-	    neighborhood_mask[pos].low |= (1 << neighbor);
+	    neighborhood_mask[pos].low |= ((unsigned int)1 << ((unsigned int)neighbor));
 	  else
 	    neighborhood_mask[pos].high |= (1 << (neighbor - 32));
 	}
diff --git a/myrandom.c b/myrandom.c
index 30c2c1c..bc1f63c 100644
--- a/myrandom.c
+++ b/myrandom.c
@@ -190,7 +190,7 @@ my_srandom(int x)
     my_state[ 0 ] = x;
     for (i = 1; i < my_rand_deg; i++)
     {
-      my_state[i] = 1103515245*my_state[i - 1] + 12345;
+      my_state[i] = ((unsigned int)1103515245)*((unsigned int)my_state[i - 1]) + ((unsigned int )12345);
     }
     my_fptr = &my_state[my_rand_sep];
     my_rptr = &my_state[0];
@@ -348,7 +348,7 @@ my_random(void)
   }
   else
   {
-    *my_fptr += *my_rptr;
+    *my_fptr = ((unsigned int)*my_fptr) + ((unsigned int)*my_rptr);
     i = (*my_fptr >> 1)&0x7fffffff; /* chucking least random bit */
     if (++my_fptr >= my_end_ptr )
     {
diff --git a/patterns.c b/patterns.c
index c14f821..585a4b2 100644
--- a/patterns.c
+++ b/patterns.c
@@ -97,7 +97,7 @@ transformation_setup( void ) {
 static void
 add_single( int mask, int pos ) {
   if ( mask < 32 )
-    depend_lo[pos] |= 1 << mask;
+    depend_lo[pos] |= ((unsigned int )1) << ((unsigned int)mask);
   else
     depend_hi[pos] |= 1 << (mask - 32);
 }
diff --git a/stable.c b/stable.c
index f4ad810..e5b828f 100644
--- a/stable.c
+++ b/stable.c
@@ -281,7 +281,7 @@ count_stable( int color,
 
   common_stable.low = edge_stable[edge_a1h1];
 
-  common_stable.high = (edge_stable[edge_a8h8] << 24);
+  common_stable.high = (((unsigned int)edge_stable[edge_a8h8]) << (unsigned int)24);
 
   t = edge_stable[edge_a1a8];
   common_stable.low |= ((t & 0x0F) * 0x00204081) & 0x01010101;
diff --git a/thordb.c b/thordb.c
index be91124..017d4ec 100644
--- a/thordb.c
+++ b/thordb.c
@@ -2522,18 +2522,18 @@ init_move_masks( void ) {
   for ( i = 0; i < 4; i++ )
     for ( j = 0, pos = 10 * i + 11; j < 8; j++, pos++ ) {
       index = 8 * i + j;
-      move_mask_lo[pos] = (1 << index);
+      move_mask_lo[pos] = (((unsigned int)1) << ((unsigned int)index));
       move_mask_hi[pos] = 0;
-      unmove_mask_lo[pos] = ~(1 << index);
+      unmove_mask_lo[pos] = ~(((unsigned int)1) << ((unsigned int)index));
       unmove_mask_hi[pos] = ~0;
     }
   for ( i = 0; i < 4; i++ )
     for ( j = 0, pos = 10 * i + 51; j < 8; j++, pos++ ) {
       index = 8 * i + j;
       move_mask_lo[pos] = 0;
-      move_mask_hi[pos] = (1 << index);
+      move_mask_hi[pos] = (((unsigned int)1) << ((unsigned int)index));
       unmove_mask_lo[pos] = ~0;
-      unmove_mask_hi[pos] = ~(1 << index);
+      unmove_mask_hi[pos] = ~(((unsigned int)1) << ((unsigned int)index));
     }
 }