diff --git a/src/util/mpz.cpp b/src/util/mpz.cpp
index 2d9768758..b877c700b 100644
--- a/src/util/mpz.cpp
+++ b/src/util/mpz.cpp
@@ -939,7 +939,6 @@ void mpz_manager<SYNCH>::big_rem(mpz const & a, mpz const & b, mpz & c) {
 
 template<bool SYNCH>
 void mpz_manager<SYNCH>::gcd(mpz const & a, mpz const & b, mpz & c) {
-    static_assert(sizeof(int) == sizeof(int), "size mismatch");
     static_assert(sizeof(mpz) <= 16, "mpz size overflow");
     if (is_small(a) && is_small(b)) {
         int64_t _a = a.value64();
diff --git a/src/util/mpz.h b/src/util/mpz.h
index 68bae1914..5d1f30c7d 100644
--- a/src/util/mpz.h
+++ b/src/util/mpz.h
@@ -99,9 +99,8 @@ private:
     static constexpr int SMALL_BITS = sizeof(uintptr_t) * 8 - 1;
     
     // Maximum and minimum values that can be stored as small integers
-    // Use unsigned arithmetic to avoid undefined behavior on left shift
-    static constexpr int64_t SMALL_INT_MAX = (static_cast<uint64_t>(1) << (SMALL_BITS - 1)) - 1;
-    static constexpr int64_t SMALL_INT_MIN = -(static_cast<int64_t>(static_cast<uint64_t>(1) << (SMALL_BITS - 1)));
+    static constexpr int64_t SMALL_INT_MAX = (static_cast<int64_t>(1) << (SMALL_BITS - 1)) - 1;
+    static constexpr int64_t SMALL_INT_MIN = -(static_cast<int64_t>(1) << (SMALL_BITS - 1));
 
     static bool fits_in_small(int64_t v) {
         return v >= SMALL_INT_MIN && v <= SMALL_INT_MAX;