diff --git a/rdrand.cpp b/rdrand.cpp
index 9aae80d9..baa3aa8f 100644
--- a/rdrand.cpp
+++ b/rdrand.cpp
@@ -59,6 +59,7 @@ NAMESPACE_BEGIN(CryptoPP)
 // Fills 4 bytes
 inline void RDRAND32(void* output)
 {
+    CRYPTOPP_UNUSED(output);  // MSC warning
 #if defined(GCC_RDRAND_ASM_AVAILABLE)
     __asm__ __volatile__
     (
@@ -75,6 +76,7 @@ inline void RDRAND32(void* output)
 // Fills 8 bytes
 inline void RDRAND64(void* output)
 {
+    CRYPTOPP_UNUSED(output);  // MSC warning
 #if defined(GCC_RDRAND_ASM_AVAILABLE)
     __asm__ __volatile__
     (
@@ -163,6 +165,7 @@ void RDRAND::DiscardBytes(size_t n)
 // Fills 4 bytes
 inline void RDSEED32(void* output)
 {
+    CRYPTOPP_UNUSED(output);  // MSC warning
 #if defined(GCC_RDSEED_ASM_AVAILABLE)
     __asm__ __volatile__
     (
@@ -179,6 +182,7 @@ inline void RDSEED32(void* output)
 // Fills 8 bytes
 inline void RDSEED64(void* output)
 {
+    CRYPTOPP_UNUSED(output);  // MSC warning
 #if defined(GCC_RDSEED_ASM_AVAILABLE)
     __asm__ __volatile__
     (
diff --git a/sha.cpp b/sha.cpp
index 951d7705..d56ef60d 100644
--- a/sha.cpp
+++ b/sha.cpp
@@ -1186,7 +1186,7 @@ void SHA512_HashBlock_CXX(word64 *state, const word64 *data)
     CRYPTOPP_ASSERT(state);
     CRYPTOPP_ASSERT(data);
 
-    word64 W[16]={0}, D[16], T[8];
+    word64 W[16]={0}, T[8];
 
     /* Copy context->state[] to working vars */
     std::memcpy(T, state, sizeof(T));