diff --git a/montgomery.cc b/montgomery.cc
index d5221f4..9fbc5da 100644
--- a/montgomery.cc
+++ b/montgomery.cc
@@ -22,8 +22,8 @@ template <typename T>
 rlwe::StatusOr<std::unique_ptr<const MontgomeryIntParams<T>>>
 MontgomeryIntParams<T>::Create(Int modulus) {
   // Check that the modulus is smaller than max(Int) / 4.
-  if (Int most_significant_bit = modulus >> (bitsize_int - 2);
-      most_significant_bit != 0) {
+  Int most_significant_bit = modulus >> (bitsize_int - 2);
+  if (most_significant_bit != 0) {
     return absl::InvalidArgumentError(absl::StrCat(
         "The modulus should be less than 2^", (bitsize_int - 2), "."));
   }
diff --git a/ntt_parameters.h b/ntt_parameters.h
index 56e1871..c3da197 100644
--- a/ntt_parameters.h
+++ b/ntt_parameters.h
@@ -103,7 +103,8 @@ static void BitrevHelper(const std::vector<unsigned int>& bitrevs,
   using std::swap;
   for (int i = 0; i < item_to_reverse->size(); i++) {
     // Only swap in one direction - don't accidentally swap twice.
-    if (unsigned int r = bitrevs[i]; i < r) {
+    unsigned int r = bitrevs[i];
+    if (static_cast<unsigned int>(i) < r) {
       swap((*item_to_reverse)[i], (*item_to_reverse)[r]);
     }
   }
diff --git a/polynomial.h b/polynomial.h
index 07843b2..3cf0c77 100644
--- a/polynomial.h
+++ b/polynomial.h
@@ -80,7 +80,8 @@ class Polynomial {
                                  const NttParameters<ModularInt>* ntt_params,
                                  const ModularIntParams* modular_params) {
     // Check to ensure that the coefficient vector is of the correct length.
-    if (int len = poly_coeffs.size(); len <= 0 || (len & (len - 1)) != 0) {
+    int len = poly_coeffs.size();
+    if (len <= 0 || (len & (len - 1)) != 0) {
       // An error value.
       return Polynomial();
     }
diff --git a/prng/chacha_prng_util.cc b/prng/chacha_prng_util.cc
index dfab1d9..c49c82d 100644
--- a/prng/chacha_prng_util.cc
+++ b/prng/chacha_prng_util.cc
@@ -24,7 +24,8 @@
 #include <openssl/rand.h>
 #include "status_macros.h"
 
-namespace rlwe::internal {
+namespace rlwe {
+namespace internal {
 
 absl::Status ChaChaPrngResalt(absl::string_view key, int buffer_size,
                               int* salt_counter, int* position_in_buffer,
@@ -85,4 +86,5 @@ rlwe::StatusOr<Uint64> ChaChaPrngRand64(absl::string_view key,
   return rand64;
 }
 
-}  // namespace rlwe::internal
+}  // namespace internal
+}  // namespace rlwe
diff --git a/prng/chacha_prng_util.h b/prng/chacha_prng_util.h
index 32cac5b..8eb8118 100644
--- a/prng/chacha_prng_util.h
+++ b/prng/chacha_prng_util.h
@@ -28,7 +28,8 @@
 #include "integral_types.h"
 #include "statusor.h"
 
-namespace rlwe::internal {
+namespace rlwe {
+namespace internal {
 
 const int kChaChaKeyBytesSize = 32;
 const int kChaChaNonceSize = 12;
@@ -59,6 +60,7 @@ rlwe::StatusOr<Uint64> ChaChaPrngRand64(absl::string_view key,
                                         int* salt_counter,
                                         std::vector<Uint8>* buffer);
 
-}  // namespace rlwe::internal
+}  // namespace internal
+}  // namespace rlwe
 
 #endif  // RLWE_CHACHA_PRNG_UTIL_H_
diff --git a/statusor.h b/statusor.h
index d8addb5..200f62d 100644
--- a/statusor.h
+++ b/statusor.h
@@ -96,7 +96,7 @@ class StatusOr {
 
   operator absl::Status() const { return status(); }
 
-  template <template <typename> typename OtherStatusOrType>
+  template <template <typename> class OtherStatusOrType>
   operator OtherStatusOrType<T>() {
     if (value_) {
       return OtherStatusOrType<T>(std::move(value_.value()));
diff --git a/symmetric_encryption.h b/symmetric_encryption.h
index e120b18..987e86f 100644
--- a/symmetric_encryption.h
+++ b/symmetric_encryption.h
@@ -571,8 +571,8 @@ class SymmetricRlweKey {
       const typename ModularIntQ::Params* modulus_params_q,
       const NttParameters<ModularIntQ>* ntt_params_q) const {
     // Configuration failure.
-    if (Int t = (modulus_params_q->One() << log_t_) + modulus_params_q->One();
-        modulus_params_->modulus % t != modulus_params_q->modulus % t) {
+    Int t = (modulus_params_q->One() << log_t_) + modulus_params_q->One();
+    if (modulus_params_->modulus % t != modulus_params_q->modulus % t) {
       return absl::InvalidArgumentError("p % t != q % t");
     }