diff --git a/src/sfizz/ScopedFTZ.cpp b/src/sfizz/ScopedFTZ.cpp
index 22c2c1e4..46ca9424 100644
--- a/src/sfizz/ScopedFTZ.cpp
+++ b/src/sfizz/ScopedFTZ.cpp
@@ -18,13 +18,13 @@ ScopedFTZ::ScopedFTZ()
 #if SFIZZ_HAVE_SSE
     unsigned mask = _MM_DENORMALS_ZERO_MASK | _MM_FLUSH_ZERO_MASK;
     registerState = _mm_getcsr();
-    _mm_setcsr((registerState & (~mask)) | mask);
+    _mm_setcsr((static_cast<unsigned>(registerState) & (~mask)) | mask);
 #elif SFIZZ_HAVE_NEON && SFIZZ_CPU_FAMILY_ARM
-    intptr_t mask = (1 << 24);
+    uintptr_t mask = 1u << 24;
     asm volatile("vmrs %0, fpscr" : "=r"(registerState));
     asm volatile("vmsr fpscr, %0" : : "r"((registerState & (~mask)) | mask));
 #elif SFIZZ_HAVE_NEON && SFIZZ_CPU_FAMILY_AARCH64
-    intptr_t mask = (1 << 24);
+    uintptr_t mask = 1u << 24;
     asm volatile("mrs %0, fpcr" : "=r"(registerState));
     asm volatile("msr fpcr, %0" : : "r"((registerState & (~mask)) | mask));
 #endif
@@ -33,7 +33,7 @@ ScopedFTZ::ScopedFTZ()
 ScopedFTZ::~ScopedFTZ()
 {
 #if SFIZZ_HAVE_SSE
-    _mm_setcsr(registerState);
+    _mm_setcsr(static_cast<unsigned>(registerState));
 #elif SFIZZ_HAVE_NEON && SFIZZ_CPU_FAMILY_ARM
     asm volatile("vmrs %0, fpscr" : : "r"(registerState));
 #elif SFIZZ_HAVE_NEON && SFIZZ_CPU_FAMILY_AARCH64
diff --git a/src/sfizz/ScopedFTZ.h b/src/sfizz/ScopedFTZ.h
index 6fea43b0..15f024d9 100644
--- a/src/sfizz/ScopedFTZ.h
+++ b/src/sfizz/ScopedFTZ.h
@@ -5,6 +5,7 @@
 // If not, contact the sfizz maintainers at https://github.com/sfztools/sfizz
 
 #pragma once
+#include <cstdint>
 
 /**
  * @brief Flush floating points to zero and disable denormals as an RAII helper.
@@ -16,5 +17,5 @@ public:
     ScopedFTZ();
     ~ScopedFTZ();
 private:
-    unsigned registerState;
+    uintptr_t registerState;
 };