diff --git a/adv-simd.h b/adv-simd.h
index 1e9e458b..4b77d04c 100644
--- a/adv-simd.h
+++ b/adv-simd.h
@@ -718,8 +718,6 @@ inline size_t GCC_NO_UBSAN AdvancedProcessBlocks64_6x2_SSE(F2 func2, F6 func6,
     CRYPTOPP_ASSERT(outBlocks);
     CRYPTOPP_ASSERT(length >= 8);
 
-    CRYPTOPP_ALIGN_DATA(16)
-    const word32 s_one32x4[] = {0, 0, 0, 1<<24};
     CRYPTOPP_ALIGN_DATA(16)
     const word32 s_one32x4_1b[] = {0, 0, 0, 1<<24};
     CRYPTOPP_ALIGN_DATA(16)
@@ -961,10 +959,6 @@ inline size_t AdvancedProcessBlocks128_6x2_SSE(F2 func2, F6 func6,
 
     CRYPTOPP_ALIGN_DATA(16)
     const word32 s_one32x4[] = {0, 0, 0, 1<<24};
-    CRYPTOPP_ALIGN_DATA(16)
-    const word32 s_one32x4_1b[] = {0, 0, 0, 1<<24};
-    CRYPTOPP_ALIGN_DATA(16)
-    const word32 s_one32x4_2b[] = {0, 2<<24, 0, 2<<24};
 
     const ptrdiff_t blockSize = 16;
     // const ptrdiff_t xmmBlockSize = 16;
@@ -1153,10 +1147,6 @@ inline size_t AdvancedProcessBlocks128_4x1_SSE(F1 func1, F4 func4,
 
     CRYPTOPP_ALIGN_DATA(16)
     const word32 s_one32x4[] = {0, 0, 0, 1<<24};
-    CRYPTOPP_ALIGN_DATA(16)
-    const word32 s_one32x4_1b[] = {0, 0, 0, 1<<24};
-    CRYPTOPP_ALIGN_DATA(16)
-    const word32 s_one32x4_2b[] = {0, 2<<24, 0, 2<<24};
 
     const ptrdiff_t blockSize = 16;
     // const ptrdiff_t xmmBlockSize = 16;
@@ -1291,10 +1281,8 @@ inline size_t AdvancedProcessBlocks128_6x1_ALTIVEC(F1 func1, F6 func6,
     CRYPTOPP_ASSERT(length >= 16);
 
 #if defined(CRYPTOPP_LITTLE_ENDIAN)
-    const uint32x4_p s_zero = {0,0,0,0};
     const uint32x4_p s_one  = {1,0,0,0};
 #else
-    const uint32x4_p s_zero = {0,0,0,0};
     const uint32x4_p s_one = {0,0,0,1};
 #endif
 
diff --git a/rijndael-simd.cpp b/rijndael-simd.cpp
index 78390a4c..628ad32d 100644
--- a/rijndael-simd.cpp
+++ b/rijndael-simd.cpp
@@ -15,9 +15,9 @@
 //    AltiVec and Power8 code based on http://github.com/noloader/AES-Intrinsics and
 //    http://www.ibm.com/developerworks/library/se-power8-in-core-cryptography/
 //    For Power8 do not remove the casts, even when const-ness is cast away. It causes
-//    a 0.3 to 0.6 cpb drop in performance. The IBM documentation absolutely sucks.
-//    Thanks to Andy Polyakov, Paul R and Trudeaun for answering questions and filling
-//    the gaps in the IBM documentation.
+//    failed compiles and a 0.3 to 0.6 cpb drop in performance. The IBM documentation
+//    absolutely sucks. Thanks to Andy Polyakov, Paul R and Trudeaun for answering
+//    questions and filling the gaps in the IBM documentation.
 //
 
 #include "pch.h"
@@ -662,7 +662,8 @@ void Rijndael_UncheckedSetKey_POWER8(const byte* userKey, size_t keyLen, word32*
     const word32 *rc = s_rconBE;
 
     GetUserKey(BIG_ENDIAN_ORDER, rk, keyLen/4, userKey, keyLen);
-    word32 *rk_saved = rk, temp;
+    word32 *rk_saved = rk, temp; // unused in big-endian
+    CRYPTOPP_UNUSED(rk_saved);
 
     // keySize: m_key allocates 4*(rounds+1) word32's.
     const size_t keySize = 4*(rounds+1);