diff --git a/crypto_kem/ntrulpr653/avx2/crypto_core_multsntrup653.c b/crypto_kem/ntrulpr653/avx2/crypto_core_multsntrup653.c
index 8c754b1f..74df5a9d 100644
--- a/crypto_kem/ntrulpr653/avx2/crypto_core_multsntrup653.c
+++ b/crypto_kem/ntrulpr653/avx2/crypto_core_multsntrup653.c
@@ -298,7 +298,7 @@ int PQCLEAN_NTRULPR653_AVX2_crypto_core_multsntrup653(unsigned char *outbytes, c
 
     mult768(fg, f, g);
 
-    fg[0] -= fg[p - 1];
+    fg[0] = (int16) (fg[0] - fg[p - 1]);
     for (i = 0; i < 768; i += 16) {
         int16x16 fgi = load_x16(&fg[i]);
         int16x16 fgip = load_x16(&fg[i + p]);
diff --git a/crypto_kem/ntrulpr653/clean/crypto_encode_653x3.c b/crypto_kem/ntrulpr653/clean/crypto_encode_653x3.c
index 2dc3dffc..0b328e94 100644
--- a/crypto_kem/ntrulpr653/clean/crypto_encode_653x3.c
+++ b/crypto_kem/ntrulpr653/clean/crypto_encode_653x3.c
@@ -10,10 +10,10 @@ void PQCLEAN_NTRULPR653_CLEAN_crypto_encode_653x3(unsigned char *s, const void *
     int i;
 
     for (i = 0; i < p / 4; ++i) {
-        x = *f++ + 1;
-        x += (uint8) ((*f++ + 1) << 2);
-        x += (uint8) ((*f++ + 1) << 4);
-        x += (uint8) ((*f++ + 1) << 6);
+        x = (uint8) (*f++ + 1);
+        x = (uint8) (x + ((*f++ + 1) << 2));
+        x = (uint8) (x + ((*f++ + 1) << 4));
+        x = (uint8) (x + ((*f++ + 1) << 6));
         *s++ = x;
     }
     x = *f++ + 1;
diff --git a/crypto_kem/ntrulpr761/avx2/crypto_core_multsntrup761.c b/crypto_kem/ntrulpr761/avx2/crypto_core_multsntrup761.c
index c5a1ce0d..b78302d2 100644
--- a/crypto_kem/ntrulpr761/avx2/crypto_core_multsntrup761.c
+++ b/crypto_kem/ntrulpr761/avx2/crypto_core_multsntrup761.c
@@ -298,7 +298,7 @@ int PQCLEAN_NTRULPR761_AVX2_crypto_core_multsntrup761(unsigned char *outbytes, c
 
     mult768(fg, f, g);
 
-    fg[0] -= fg[p - 1];
+    fg[0] = (int16) (fg[0] - fg[p - 1]);
     for (i = 0; i < 768; i += 16) {
         int16x16 fgi = load_x16(&fg[i]);
         int16x16 fgip = load_x16(&fg[i + p]);
diff --git a/crypto_kem/ntrulpr761/clean/crypto_encode_761x3.c b/crypto_kem/ntrulpr761/clean/crypto_encode_761x3.c
index 7f9bd4d4..68be7bb0 100644
--- a/crypto_kem/ntrulpr761/clean/crypto_encode_761x3.c
+++ b/crypto_kem/ntrulpr761/clean/crypto_encode_761x3.c
@@ -5,15 +5,15 @@
 #define p 761
 
 void PQCLEAN_NTRULPR761_CLEAN_crypto_encode_761x3(unsigned char *s, const void *v) {
-    const uint8 *f = v;
+    const uint8 *f = (const uint8 *)v;
     uint8 x;
     int i;
 
     for (i = 0; i < p / 4; ++i) {
-        x = *f++ + 1;
-        x += (uint8) ((*f++ + 1) << 2);
-        x += (uint8) ((*f++ + 1) << 4);
-        x += (uint8) ((*f++ + 1) << 6);
+        x = (uint8) (*f++ + 1);
+        x = (uint8) (x + ((*f++ + 1) << 2));
+        x = (uint8) (x + ((*f++ + 1) << 4));
+        x = (uint8) (x + ((*f++ + 1) << 6));
         *s++ = x;
     }
     x = *f++ + 1;
diff --git a/crypto_kem/ntrulpr857/avx2/crypto_core_multsntrup857.c b/crypto_kem/ntrulpr857/avx2/crypto_core_multsntrup857.c
index 9138df20..e4e12728 100644
--- a/crypto_kem/ntrulpr857/avx2/crypto_core_multsntrup857.c
+++ b/crypto_kem/ntrulpr857/avx2/crypto_core_multsntrup857.c
@@ -405,7 +405,7 @@ int PQCLEAN_NTRULPR857_AVX2_crypto_core_multsntrup857(unsigned char *outbytes, c
 
     mult1024(fg, f, g);
 
-    fg[0] -= fg[p - 1];
+    fg[0] = (int16) (fg[0] - fg[p - 1]);
     for (i = 0; i < 1024; i += 16) {
         int16x16 fgi = load_x16(&fg[i]);
         int16x16 fgip = load_x16(&fg[i + p]);
diff --git a/crypto_kem/ntrulpr857/clean/crypto_encode_857x3.c b/crypto_kem/ntrulpr857/clean/crypto_encode_857x3.c
index d0646e88..e4660fa7 100644
--- a/crypto_kem/ntrulpr857/clean/crypto_encode_857x3.c
+++ b/crypto_kem/ntrulpr857/clean/crypto_encode_857x3.c
@@ -10,10 +10,10 @@ void PQCLEAN_NTRULPR857_CLEAN_crypto_encode_857x3(unsigned char *s, const void *
     int i;
 
     for (i = 0; i < p / 4; ++i) {
-        x = *f++ + 1;
-        x += (uint8) ((*f++ + 1) << 2);
-        x += (uint8) ((*f++ + 1) << 4);
-        x += (uint8) ((*f++ + 1) << 6);
+        x = (uint8) (*f++ + 1);
+        x = (uint8) (x + ((*f++ + 1) << 2));
+        x = (uint8) (x + ((*f++ + 1) << 4));
+        x = (uint8) (x + ((*f++ + 1) << 6));
         *s++ = x;
     }
     x = *f++ + 1;
diff --git a/crypto_kem/sntrup653/avx2/crypto_core_multsntrup653.c b/crypto_kem/sntrup653/avx2/crypto_core_multsntrup653.c
index 7af7050b..6793709d 100644
--- a/crypto_kem/sntrup653/avx2/crypto_core_multsntrup653.c
+++ b/crypto_kem/sntrup653/avx2/crypto_core_multsntrup653.c
@@ -298,7 +298,7 @@ int PQCLEAN_SNTRUP653_AVX2_crypto_core_multsntrup653(unsigned char *outbytes, co
 
     mult768(fg, f, g);
 
-    fg[0] -= fg[p - 1];
+    fg[0] = (int16) (fg[0] - fg[p - 1]);
     for (i = 0; i < 768; i += 16) {
         int16x16 fgi = load_x16(&fg[i]);
         int16x16 fgip = load_x16(&fg[i + p]);
diff --git a/crypto_kem/sntrup653/clean/crypto_core_inv3sntrup653.c b/crypto_kem/sntrup653/clean/crypto_core_inv3sntrup653.c
index ef09babe..d63459a5 100644
--- a/crypto_kem/sntrup653/clean/crypto_core_inv3sntrup653.c
+++ b/crypto_kem/sntrup653/clean/crypto_core_inv3sntrup653.c
@@ -74,7 +74,7 @@ int PQCLEAN_SNTRUP653_CLEAN_crypto_core_inv3sntrup653(unsigned char *outbytes, c
         v[0] = 0;
 
         sign = -g[0] * f[0];
-        swap = int16_negative_mask(-(int16) delta) & int16_nonzero_mask(g[0]);
+        swap = int16_negative_mask((int16) - delta) & int16_nonzero_mask(g[0]);
         delta ^= swap & (delta ^ -delta);
         delta += 1;
 
@@ -102,7 +102,7 @@ int PQCLEAN_SNTRUP653_CLEAN_crypto_core_inv3sntrup653(unsigned char *outbytes, c
 
     sign = f[0];
     for (i = 0; i < p; ++i) {
-        out[i] = (small) sign * v[p - 1 - i];
+        out[i] = (small) (sign * v[p - 1 - i]);
     }
 
     out[p] = (small) int16_nonzero_mask((int16) delta);
diff --git a/crypto_kem/sntrup653/clean/crypto_encode_653x3.c b/crypto_kem/sntrup653/clean/crypto_encode_653x3.c
index 61ae2eed..4fc93036 100644
--- a/crypto_kem/sntrup653/clean/crypto_encode_653x3.c
+++ b/crypto_kem/sntrup653/clean/crypto_encode_653x3.c
@@ -10,10 +10,10 @@ void PQCLEAN_SNTRUP653_CLEAN_crypto_encode_653x3(unsigned char *s, const void *v
     int i;
 
     for (i = 0; i < p / 4; ++i) {
-        x = *f++ + 1;
-        x += (uint8) ((*f++ + 1) << 2);
-        x += (uint8) ((*f++ + 1) << 4);
-        x += (uint8) ((*f++ + 1) << 6);
+        x = (uint8) (*f++ + 1);
+        x = (uint8) (x + ((*f++ + 1) << 2));
+        x = (uint8) (x + ((*f++ + 1) << 4));
+        x = (uint8) (x + ((*f++ + 1) << 6));
         *s++ = x;
     }
     x = *f++ + 1;
diff --git a/crypto_kem/sntrup761/avx2/crypto_core_multsntrup761.c b/crypto_kem/sntrup761/avx2/crypto_core_multsntrup761.c
index 87253477..7ee2997a 100644
--- a/crypto_kem/sntrup761/avx2/crypto_core_multsntrup761.c
+++ b/crypto_kem/sntrup761/avx2/crypto_core_multsntrup761.c
@@ -298,7 +298,7 @@ int PQCLEAN_SNTRUP761_AVX2_crypto_core_multsntrup761(unsigned char *outbytes, co
 
     mult768(fg, f, g);
 
-    fg[0] -= fg[p - 1];
+    fg[0] = (int16) (fg[0] - fg[p - 1]);
     for (i = 0; i < 768; i += 16) {
         int16x16 fgi = load_x16(&fg[i]);
         int16x16 fgip = load_x16(&fg[i + p]);
diff --git a/crypto_kem/sntrup761/clean/crypto_core_inv3sntrup761.c b/crypto_kem/sntrup761/clean/crypto_core_inv3sntrup761.c
index 99342bce..1aba59e9 100644
--- a/crypto_kem/sntrup761/clean/crypto_core_inv3sntrup761.c
+++ b/crypto_kem/sntrup761/clean/crypto_core_inv3sntrup761.c
@@ -74,7 +74,7 @@ int PQCLEAN_SNTRUP761_CLEAN_crypto_core_inv3sntrup761(unsigned char *outbytes, c
         v[0] = 0;
 
         sign = -g[0] * f[0];
-        swap = int16_negative_mask(-(int16) delta) & int16_nonzero_mask(g[0]);
+        swap = int16_negative_mask((int16) - delta) & int16_nonzero_mask(g[0]);
         delta ^= swap & (delta ^ -delta);
         delta += 1;
 
@@ -102,7 +102,7 @@ int PQCLEAN_SNTRUP761_CLEAN_crypto_core_inv3sntrup761(unsigned char *outbytes, c
 
     sign = f[0];
     for (i = 0; i < p; ++i) {
-        out[i] = (small) sign * v[p - 1 - i];
+        out[i] = (small) (sign * v[p - 1 - i]);
     }
 
     out[p] = (small) int16_nonzero_mask((int16) delta);
diff --git a/crypto_kem/sntrup761/clean/crypto_encode_761x3.c b/crypto_kem/sntrup761/clean/crypto_encode_761x3.c
index 32d00f3b..7bb35adb 100644
--- a/crypto_kem/sntrup761/clean/crypto_encode_761x3.c
+++ b/crypto_kem/sntrup761/clean/crypto_encode_761x3.c
@@ -5,15 +5,15 @@
 #define p 761
 
 void PQCLEAN_SNTRUP761_CLEAN_crypto_encode_761x3(unsigned char *s, const void *v) {
-    const uint8 *f = v;
+    const uint8 *f = (const uint8 *)v;
     uint8 x;
     int i;
 
     for (i = 0; i < p / 4; ++i) {
-        x = *f++ + 1;
-        x += (uint8) ((*f++ + 1) << 2);
-        x += (uint8) ((*f++ + 1) << 4);
-        x += (uint8) ((*f++ + 1) << 6);
+        x = (uint8) (*f++ + 1);
+        x = (uint8) (x + ((*f++ + 1) << 2));
+        x = (uint8) (x + ((*f++ + 1) << 4));
+        x = (uint8) (x + ((*f++ + 1) << 6));
         *s++ = x;
     }
     x = *f++ + 1;
diff --git a/crypto_kem/sntrup857/avx2/crypto_core_multsntrup857.c b/crypto_kem/sntrup857/avx2/crypto_core_multsntrup857.c
index 898c7297..dbaabc56 100644
--- a/crypto_kem/sntrup857/avx2/crypto_core_multsntrup857.c
+++ b/crypto_kem/sntrup857/avx2/crypto_core_multsntrup857.c
@@ -405,7 +405,7 @@ int PQCLEAN_SNTRUP857_AVX2_crypto_core_multsntrup857(unsigned char *outbytes, co
 
     mult1024(fg, f, g);
 
-    fg[0] -= fg[p - 1];
+    fg[0] = (int16) (fg[0] - fg[p - 1]);
     for (i = 0; i < 1024; i += 16) {
         int16x16 fgi = load_x16(&fg[i]);
         int16x16 fgip = load_x16(&fg[i + p]);
diff --git a/crypto_kem/sntrup857/clean/crypto_core_inv3sntrup857.c b/crypto_kem/sntrup857/clean/crypto_core_inv3sntrup857.c
index 6ea2adcb..c053c761 100644
--- a/crypto_kem/sntrup857/clean/crypto_core_inv3sntrup857.c
+++ b/crypto_kem/sntrup857/clean/crypto_core_inv3sntrup857.c
@@ -74,7 +74,7 @@ int PQCLEAN_SNTRUP857_CLEAN_crypto_core_inv3sntrup857(unsigned char *outbytes, c
         v[0] = 0;
 
         sign = -g[0] * f[0];
-        swap = int16_negative_mask(-(int16) delta) & int16_nonzero_mask(g[0]);
+        swap = int16_negative_mask((int16) - delta) & int16_nonzero_mask(g[0]);
         delta ^= swap & (delta ^ -delta);
         delta += 1;
 
@@ -102,7 +102,7 @@ int PQCLEAN_SNTRUP857_CLEAN_crypto_core_inv3sntrup857(unsigned char *outbytes, c
 
     sign = f[0];
     for (i = 0; i < p; ++i) {
-        out[i] = (small) sign * v[p - 1 - i];
+        out[i] = (small) (sign * v[p - 1 - i]);
     }
 
     out[p] = (small) int16_nonzero_mask((int16) delta);
diff --git a/crypto_kem/sntrup857/clean/crypto_encode_857x3.c b/crypto_kem/sntrup857/clean/crypto_encode_857x3.c
index 2db8d7ea..75002c0f 100644
--- a/crypto_kem/sntrup857/clean/crypto_encode_857x3.c
+++ b/crypto_kem/sntrup857/clean/crypto_encode_857x3.c
@@ -10,10 +10,10 @@ void PQCLEAN_SNTRUP857_CLEAN_crypto_encode_857x3(unsigned char *s, const void *v
     int i;
 
     for (i = 0; i < p / 4; ++i) {
-        x = *f++ + 1;
-        x += (uint8) ((*f++ + 1) << 2);
-        x += (uint8) ((*f++ + 1) << 4);
-        x += (uint8) ((*f++ + 1) << 6);
+        x = (uint8) (*f++ + 1);
+        x = (uint8) (x + ((*f++ + 1) << 2));
+        x = (uint8) (x + ((*f++ + 1) << 4));
+        x = (uint8) (x + ((*f++ + 1) << 6));
         *s++ = x;
     }
     x = *f++ + 1;