diff --git a/externals/mcl/CMakeLists.txt b/externals/mcl/CMakeLists.txt
index c9d526e5..3bf31637 100644
--- a/externals/mcl/CMakeLists.txt
+++ b/externals/mcl/CMakeLists.txt
@@ -1,7 +1,7 @@
 cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
 include(GNUInstallDirs)
 
-project(mcl LANGUAGES CXX VERSION 0.1.6)
+project(mcl LANGUAGES CXX VERSION 0.1.7)
 
 # Project options
 option(MCL_WARNINGS_AS_ERRORS "Warnings as errors" ON)
diff --git a/externals/mcl/include/mcl/bit/bit_field.hpp b/externals/mcl/include/mcl/bit/bit_field.hpp
index c09eda0a..b967ed4b 100644
--- a/externals/mcl/include/mcl/bit/bit_field.hpp
+++ b/externals/mcl/include/mcl/bit/bit_field.hpp
@@ -143,11 +143,9 @@ template<size_t bit_count, BitIntegral T>
 constexpr T sign_extend(T value) {
     static_assert(bit_count != 0, "cannot sign-extend zero-sized value");
 
-    constexpr T m = ones<bit_count, T>();
-    if (get_bit<bit_count - 1, T>(value)) {
-        return value | ~m;
-    }
-    return value;
+    using S = std::make_signed_t<T>;
+    constexpr size_t shift_amount = bitsizeof<T> - bit_count;
+    return static_cast<T>(static_cast<S>(value << shift_amount) >> shift_amount);
 }
 
 /// Sign-extends a value that has bit_count bits to the full bitwidth of type T.
@@ -155,11 +153,9 @@ template<BitIntegral T>
 constexpr T sign_extend(size_t bit_count, T value) {
     ASSERT_MSG(bit_count != 0, "cannot sign-extend zero-sized value");
 
-    const T m = ones<T>(bit_count);
-    if (get_bit<T>(bit_count - 1, value)) {
-        return value | ~m;
-    }
-    return value;
+    using S = std::make_signed_t<T>;
+    const size_t shift_amount = bitsizeof<T> - bit_count;
+    return static_cast<T>(static_cast<S>(value << shift_amount) >> shift_amount);
 }
 
 /// Replicate an element across a value of type T.