diff --git a/LeopardCommon.h b/LeopardCommon.h
index 715c1c7..0ceb508 100644
--- a/LeopardCommon.h
+++ b/LeopardCommon.h
@@ -321,7 +321,8 @@ LEO_FORCE_INLINE unsigned LastNonzeroBit32(unsigned x)
     return (unsigned)index;
 #else
     // Note: Ignoring return value of 0 because x != 0
-    return 31 - (unsigned)__builtin_clzl(x);
+    static_assert(sizeof(unsigned) == 4, "Assuming 32 bit unsigneds in LastNonzeroBit32");
+    return 31 - (unsigned)__builtin_clz(x);
 #endif
 }
 
diff --git a/LeopardFF16.cpp b/LeopardFF16.cpp
index f861803..2277f41 100644
--- a/LeopardFF16.cpp
+++ b/LeopardFF16.cpp
@@ -936,7 +936,7 @@ static void FFTInitialize()
         }
     }
 
-    for (unsigned i = 0; i < kOrder; ++i)
+    for (unsigned i = 0; i < kModulus; ++i)
         FFTSkew[i] = LogLUT[FFTSkew[i]];
 
     // Precalculate FWHT(Log[i]):
@@ -1019,7 +1019,7 @@ void ReedSolomonEncode(
     unsigned original_count,
     unsigned recovery_count,
     unsigned m,
-    void* const * data,
+    const void* const * data,
     void** work)
 {
     // work <- data
@@ -1057,6 +1057,7 @@ void ReedSolomonEncode(
         }
     }
 
+    const unsigned last_count = original_count % m;
     if (m >= original_count)
         goto skip_body;
 
@@ -1100,7 +1101,6 @@ void ReedSolomonEncode(
             temp);
     }
 
-    const unsigned last_count = original_count % m;
     if (last_count != 0)
     {
         const unsigned i = original_count - last_count;
@@ -1296,8 +1296,8 @@ void ReedSolomonDecode(
     unsigned recovery_count,
     unsigned m, // NextPow2(recovery_count)
     unsigned n, // NextPow2(m + original_count) = work_count
-    void* const * const original, // original_count entries
-    void* const * const recovery, // recovery_count entries
+    const void* const * const original, // original_count entries
+    const void* const * const recovery, // recovery_count entries
     void** work) // n entries
 {
     // Fill in error locations
diff --git a/LeopardFF16.h b/LeopardFF16.h
index a335d0f..5b9f43b 100644
--- a/LeopardFF16.h
+++ b/LeopardFF16.h
@@ -67,7 +67,7 @@ static const unsigned kPolynomial = 0x1002D;
 // Fast Walsh-Hadamard Transform (FWHT) (mod kModulus)
 
 // Transform for a variable number of bits (up to kOrder)
-void FWHT(ffe_t* data, const unsigned bits);
+//void FWHT(ffe_t* data, const unsigned bits);
 
 // Transform specialized for the finite field order
 void FWHT(ffe_t data[kOrder]);
@@ -118,7 +118,7 @@ void ReedSolomonEncode(
     unsigned original_count,
     unsigned recovery_count,
     unsigned m, // = NextPow2(recovery_count) * 2 = work_count
-    void* const * const data,
+    const void* const * const data,
     void** work); // Size of GetEncodeWorkCount()
 
 
@@ -131,8 +131,8 @@ void ReedSolomonDecode(
     unsigned recovery_count,
     unsigned m, // = NextPow2(recovery_count)
     unsigned n, // = NextPow2(m + original_count) = work_count
-    void* const * const original, // original_count entries
-    void* const * const recovery, // recovery_count entries
+    const void* const * const original, // original_count entries
+    const void* const * const recovery, // recovery_count entries
     void** work); // n entries
 
 
diff --git a/LeopardFF8.cpp b/LeopardFF8.cpp
index 026854c..50fe70a 100644
--- a/LeopardFF8.cpp
+++ b/LeopardFF8.cpp
@@ -416,7 +416,7 @@ static void FFTInitialize()
         }
     }
 
-    for (unsigned i = 0; i < kOrder; ++i)
+    for (unsigned i = 0; i < kModulus; ++i)
         FFTSkew[i] = LogLUT[FFTSkew[i]];
 
     // Precalculate FWHT(Log[i]):
@@ -783,7 +783,7 @@ static void IFFT_DIT4(
 
 void IFFT_DIT(
     const uint64_t bytes,
-    void* const* data,
+    const void* const* data,
     const unsigned m_truncated,
     void** work,
     void** xor_result,
@@ -1274,7 +1274,7 @@ void ReedSolomonEncode(
     unsigned original_count,
     unsigned recovery_count,
     unsigned m,
-    void* const* data,
+    const void* const* data,
     void** work)
 {
     // work <- IFFT(data, m, m)
@@ -1290,6 +1290,7 @@ void ReedSolomonEncode(
         m,
         skewLUT);
 
+    const unsigned last_count = original_count % m;
     if (m >= original_count)
         goto skip_body;
 
@@ -1312,7 +1313,6 @@ void ReedSolomonEncode(
     }
 
     // Handle final partial set of m pieces:
-    const unsigned last_count = original_count % m;
     if (last_count != 0)
     {
         const unsigned i = original_count - last_count;
@@ -1481,8 +1481,8 @@ void ReedSolomonDecode(
     unsigned recovery_count,
     unsigned m, // NextPow2(recovery_count)
     unsigned n, // NextPow2(m + original_count) = work_count
-    void* const * const original, // original_count entries
-    void* const * const recovery, // recovery_count entries
+    const void* const * const original, // original_count entries
+    const void* const * const recovery, // recovery_count entries
     void** work) // n entries
 {
     // Fill in error locations
diff --git a/LeopardFF8.h b/LeopardFF8.h
index 03d4e06..9962e55 100644
--- a/LeopardFF8.h
+++ b/LeopardFF8.h
@@ -68,7 +68,7 @@ static const unsigned kPolynomial = 0x11D;
 
 // Transform for a variable number of elements
 // m_truncated: Number of elements that are non-zero at the front of data
-void FWHT(ffe_t* data, const unsigned m, const unsigned m_truncated);
+//void FWHT(ffe_t* data, const unsigned m, const unsigned m_truncated);
 
 
 //------------------------------------------------------------------------------
@@ -129,7 +129,7 @@ void ReedSolomonEncode(
     unsigned original_count,
     unsigned recovery_count,
     unsigned m, // = NextPow2(recovery_count) * 2 = work_count
-    void* const * const data,
+    const void* const * const data,
     void** work); // Size of GetEncodeWorkCount()
 
 
@@ -142,8 +142,8 @@ void ReedSolomonDecode(
     unsigned recovery_count,
     unsigned m, // = NextPow2(recovery_count)
     unsigned n, // = NextPow2(m + original_count) = work_count
-    void* const * const original, // original_count entries
-    void* const * const recovery, // recovery_count entries
+    const void* const * const original, // original_count entries
+    const void* const * const recovery, // recovery_count entries
     void** work); // n entries
 
 
diff --git a/leopard.cpp b/leopard.cpp
index 4163e15..4baed74 100644
--- a/leopard.cpp
+++ b/leopard.cpp
@@ -105,7 +105,7 @@ LEO_EXPORT unsigned leo_encode_work_count(
 static void EncodeM1(
     uint64_t buffer_bytes,
     unsigned original_count,
-    void* const * const original_data,
+    const void* const * const original_data,
     void* recovery_data)
 {
     memcpy(recovery_data, original_data[0], buffer_bytes);
@@ -120,13 +120,13 @@ static void EncodeM1(
 }
 
 LEO_EXPORT LeopardResult leo_encode(
-    uint64_t buffer_bytes,              // Number of bytes in each data buffer
-    unsigned original_count,            // Number of original_data[] buffer pointers
-    unsigned recovery_count,            // Number of recovery_data[] buffer pointers
-    unsigned work_count,                // Number of work_data[] buffer pointers, from leo_encode_work_count()
-    void* const * const original_data,  // Array of pointers to original data buffers
-    void** work_data,                   // Array of work buffers
-    unsigned flags)                     // Operation flags
+    uint64_t buffer_bytes,                    // Number of bytes in each data buffer
+    unsigned original_count,                  // Number of original_data[] buffer pointers
+    unsigned recovery_count,                  // Number of recovery_data[] buffer pointers
+    unsigned work_count,                      // Number of work_data[] buffer pointers, from leo_encode_work_count()
+    const void* const * const original_data,  // Array of pointers to original data buffers
+    void** work_data,                         // Array of work buffers
+    unsigned flags)                           // Operation flags
 {
     if (buffer_bytes <= 0 || buffer_bytes % 64 != 0)
         return Leopard_InvalidSize;
@@ -216,7 +216,7 @@ LEO_EXPORT unsigned leo_decode_work_count(
 static void DecodeM1(
     uint64_t buffer_bytes,
     unsigned original_count,
-    void* const * const original_data,
+    const void* const * original_data,
     const void* recovery_data,
     void* work_data)
 {
@@ -233,14 +233,14 @@ static void DecodeM1(
 }
 
 LEO_EXPORT LeopardResult leo_decode(
-    uint64_t buffer_bytes,              // Number of bytes in each data buffer
-    unsigned original_count,            // Number of original_data[] buffer pointers
-    unsigned recovery_count,            // Number of recovery_data[] buffer pointers
-    unsigned work_count,                // Number of buffer pointers in work_data[]
-    void* const * const original_data,  // Array of original data buffers
-    void* const * const recovery_data,  // Array of recovery data buffers
-    void** work_data,                   // Array of work data buffers
-    unsigned flags)                     // Operation flags
+    uint64_t buffer_bytes,                    // Number of bytes in each data buffer
+    unsigned original_count,                  // Number of original_data[] buffer pointers
+    unsigned recovery_count,                  // Number of recovery_data[] buffer pointers
+    unsigned work_count,                      // Number of buffer pointers in work_data[]
+    const void* const * const original_data,  // Array of original data buffers
+    const void* const * const recovery_data,  // Array of recovery data buffers
+    void** work_data,                         // Array of work data buffers
+    unsigned flags)                           // Operation flags
 {
     if (buffer_bytes <= 0 || buffer_bytes % 64 != 0)
         return Leopard_InvalidSize;
diff --git a/leopard.h b/leopard.h
index cf6a3be..e6ee529 100644
--- a/leopard.h
+++ b/leopard.h
@@ -187,13 +187,13 @@ LEO_EXPORT unsigned leo_encode_work_count(
     Returns other values on errors.
 */
 LEO_EXPORT LeopardResult leo_encode(
-    uint64_t buffer_bytes,              // Number of bytes in each data buffer
-    unsigned original_count,            // Number of original_data[] buffer pointers
-    unsigned recovery_count,            // Number of recovery_data[] buffer pointers
-    unsigned work_count,                // Number of work_data[] buffer pointers, from leo_encode_work_count()
-    void* const * const original_data,  // Array of pointers to original data buffers
-    void** work_data,                   // Array of work buffers
-    unsigned flags);                    // Operation flags
+    uint64_t buffer_bytes,                    // Number of bytes in each data buffer
+    unsigned original_count,                  // Number of original_data[] buffer pointers
+    unsigned recovery_count,                  // Number of recovery_data[] buffer pointers
+    unsigned work_count,                      // Number of work_data[] buffer pointers, from leo_encode_work_count()
+    const void* const * const original_data,  // Array of pointers to original data buffers
+    void** work_data,                         // Array of work buffers
+    unsigned flags);                          // Operation flags
 
 
 //------------------------------------------------------------------------------
@@ -236,14 +236,14 @@ LEO_EXPORT unsigned leo_decode_work_count(
     Returns other values on errors.
 */
 LEO_EXPORT LeopardResult leo_decode(
-    uint64_t buffer_bytes,              // Number of bytes in each data buffer
-    unsigned original_count,            // Number of original_data[] buffer pointers
-    unsigned recovery_count,            // Number of recovery_data[] buffer pointers
-    unsigned work_count,                // Number of buffer pointers in work_data[]
-    void* const * const original_data,  // Array of original data buffers
-    void* const * const recovery_data,  // Array of recovery data buffers
-    void** work_data,                   // Array of work data buffers
-    unsigned flags);                    // Operation flags
+    uint64_t buffer_bytes,                    // Number of bytes in each data buffer
+    unsigned original_count,                  // Number of original_data[] buffer pointers
+    unsigned recovery_count,                  // Number of recovery_data[] buffer pointers
+    unsigned work_count,                      // Number of buffer pointers in work_data[]
+    const void* const * const original_data,  // Array of original data buffers
+    const void* const * const recovery_data,  // Array of recovery data buffers
+    void** work_data,                         // Array of work data buffers
+    unsigned flags);                          // Operation flags
 
 
 #ifdef __cplusplus