diff --git a/configure.ac b/configure.ac
index 2e134be97..63c890002 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1341,9 +1341,11 @@ AC_ARG_ENABLE([smallstack],
     [ ENABLED_SMALL_STACK=yes ]
     )
 
-if test "$ENABLED_SMALL_STACK" = "no"
+if test "x$ENABLED_SMALL_STACK" = "xyes"
 then
-    AM_CFLAGS="$AM_CFLAGS -DNO_SMALL_STACK"
+    AM_CFLAGS="$AM_CFLAGS -DCYASSL_SMALL_STACK"
+else
+    AM_CFLAGS="$AM_CFLAGS -DNO_CYASSL_SMALL_STACK"
 fi
 
 
diff --git a/ctaocrypt/src/blake2b.c b/ctaocrypt/src/blake2b.c
index 77b736d22..a9d1753ac 100644
--- a/ctaocrypt/src/blake2b.c
+++ b/ctaocrypt/src/blake2b.c
@@ -163,7 +163,7 @@ int blake2b_init_key( blake2b_state *S, const byte outlen, const void *key,
   if( blake2b_init_param( S, P ) < 0 ) return -1;
 
   {
-#ifndef NO_SMALL_STACK
+#ifdef CYASSL_SMALL_STACK
     byte* block;
 
     block = (byte*)XMALLOC(BLAKE2B_BLOCKBYTES, NULL, DYNAMIC_TYPE_TMP_BUFFER);
@@ -179,7 +179,7 @@ int blake2b_init_key( blake2b_state *S, const byte outlen, const void *key,
     secure_zero_memory( block, BLAKE2B_BLOCKBYTES ); /* Burn the key from */
                                                      /* memory */
 
-#ifndef NO_SMALL_STACK
+#ifdef CYASSL_SMALL_STACK
     XFREE(block, NULL, DYNAMIC_TYPE_TMP_BUFFER);
 #endif
   }
@@ -191,7 +191,7 @@ static int blake2b_compress( blake2b_state *S,
 {
   int i;
 
-#ifndef NO_SMALL_STACK
+#ifdef CYASSL_SMALL_STACK
   word64* m;
   word64* v;
 
@@ -266,7 +266,7 @@ static int blake2b_compress( blake2b_state *S,
 #undef G
 #undef ROUND
 
-#ifndef NO_SMALL_STACK
+#ifdef CYASSL_SMALL_STACK
   XFREE(m, NULL, DYNAMIC_TYPE_TMP_BUFFER);
   XFREE(v, NULL, DYNAMIC_TYPE_TMP_BUFFER);
 #endif
diff --git a/ctaocrypt/src/camellia.c b/ctaocrypt/src/camellia.c
index e177896fd..eaed4c90b 100644
--- a/ctaocrypt/src/camellia.c
+++ b/ctaocrypt/src/camellia.c
@@ -491,6 +491,8 @@ static int camellia_setup128(const unsigned char *key, u32 *subkey)
     u32 kll, klr, krl, krr;
     u32 il, ir, t0, t1, w0, w1;
     u32 kw4l, kw4r, dw, tl, tr;
+
+#ifdef CYASSL_SMALL_STACK
     u32* subL;
     u32* subR;
 
@@ -503,6 +505,10 @@ static int camellia_setup128(const unsigned char *key, u32 *subkey)
         XFREE(subL, NULL, DYNAMIC_TYPE_TMP_BUFFER);
         return MEMORY_E;
     }
+#else
+    u32 subL[26];
+    u32 subR[26];
+#endif
 
     /**
      *  k == kll || klr || krl || krr (|| is concatination)
@@ -704,8 +710,10 @@ static int camellia_setup128(const unsigned char *key, u32 *subkey)
     dw = CamelliaSubkeyL(23) ^ CamelliaSubkeyR(23), dw = CAMELLIA_RL8(dw);
     CamelliaSubkeyR(23) = CamelliaSubkeyL(23) ^ dw, CamelliaSubkeyL(23) = dw;
 
+#ifdef CYASSL_SMALL_STACK
     XFREE(subL, NULL, DYNAMIC_TYPE_TMP_BUFFER);
     XFREE(subR, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+#endif
 
     return 0;
 }
@@ -716,6 +724,8 @@ static int camellia_setup256(const unsigned char *key, u32 *subkey)
     u32 krll,krlr,krrl,krrr;       /* right half of key */
     u32 il, ir, t0, t1, w0, w1;    /* temporary variables */
     u32 kw4l, kw4r, dw, tl, tr;
+
+#ifdef CYASSL_SMALL_STACK
     u32* subL;
     u32* subR;
 
@@ -728,6 +738,10 @@ static int camellia_setup256(const unsigned char *key, u32 *subkey)
         XFREE(subL, NULL, DYNAMIC_TYPE_TMP_BUFFER);
         return MEMORY_E;
     }
+#else
+    u32 subL[34];
+    u32 subR[34];
+#endif
 
     /**
      *  key = (kll || klr || krl || krr || krll || krlr || krrl || krrr)
@@ -1003,8 +1017,10 @@ static int camellia_setup256(const unsigned char *key, u32 *subkey)
     dw = CamelliaSubkeyL(31) ^ CamelliaSubkeyR(31), dw = CAMELLIA_RL8(dw);
     CamelliaSubkeyR(31) = CamelliaSubkeyL(31) ^ dw,CamelliaSubkeyL(31) = dw;
     
+#ifdef CYASSL_SMALL_STACK
     XFREE(subL, NULL, DYNAMIC_TYPE_TMP_BUFFER);
     XFREE(subR, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+#endif
 
     return 0;
 }
diff --git a/ctaocrypt/src/des3.c b/ctaocrypt/src/des3.c
index 98fa2d8e7..dc1aac910 100644
--- a/ctaocrypt/src/des3.c
+++ b/ctaocrypt/src/des3.c
@@ -988,12 +988,16 @@ static INLINE void FPERM(word32* left, word32* right)
 
 static int DesSetKey(const byte* key, int dir, word32* out)
 {
+#ifdef CYASSL_SMALL_STACK
     byte* buffer = (byte*)XMALLOC(56+56+8, NULL, DYNAMIC_TYPE_TMP_BUFFER);
 
-    if (!buffer) {
+    if (buffer == NULL)
         return MEMORY_E;
-    }
-    else {
+#else
+    byte buffer[56+56+8];
+#endif
+
+    {
         byte* const  pc1m = buffer;               /* place to modify pc1 into */
         byte* const  pcr  = pc1m + 56;            /* place to rotate pc1 into */
         byte* const  ks   = pcr  + 56;
@@ -1048,7 +1052,9 @@ static int DesSetKey(const byte* key, int dir, word32* out)
             }
         }
 
+#ifdef CYASSL_SMALL_STACK
         XFREE(buffer, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+#endif
     }
 
     return 0;
diff --git a/ctaocrypt/src/sha256.c b/ctaocrypt/src/sha256.c
index 30f639efb..2a0d1f979 100644
--- a/ctaocrypt/src/sha256.c
+++ b/ctaocrypt/src/sha256.c
@@ -133,12 +133,17 @@ static const word32 K[64] = {
 static int Transform(Sha256* sha256)
 {
     word32 S[8], t0, t1;
-    word32* W;
     int i;
 
+#ifdef CYASSL_SMALL_STACK
+    word32* W;
+
     W = (word32*) XMALLOC(sizeof(word32) * 64, NULL, DYNAMIC_TYPE_TMP_BUFFER);
     if (W == NULL)
         return MEMORY_E;
+#else
+    word32 W[64];
+#endif
 
     /* Copy context->state[] to working vars */
     for (i = 0; i < 8; i++)
@@ -166,7 +171,9 @@ static int Transform(Sha256* sha256)
         sha256->digest[i] += S[i];
     }
 
+#ifdef CYASSL_SMALL_STACK
     XFREE(W, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+#endif
 
     return 0;
 }
diff --git a/ctaocrypt/src/sha512.c b/ctaocrypt/src/sha512.c
index 81595b8d0..ceb5a7e72 100644
--- a/ctaocrypt/src/sha512.c
+++ b/ctaocrypt/src/sha512.c
@@ -149,11 +149,16 @@ static int Transform(Sha512* sha512)
 
     word32 j;
     word64 T[8];
+
+#ifdef CYASSL_SMALL_STACK
     word64* W;
 
     W = (word64*) XMALLOC(sizeof(word64) * 16, NULL, DYNAMIC_TYPE_TMP_BUFFER);
     if (W == NULL)
         return MEMORY_E;
+#else
+    word64 W[16];
+#endif
 
     /* Copy digest to working vars */
     XMEMCPY(T, sha512->digest, sizeof(T));
@@ -192,7 +197,9 @@ static int Transform(Sha512* sha512)
     XMEMSET(W, 0, sizeof(word64) * 16);
     XMEMSET(T, 0, sizeof(T));
 
+#ifdef CYASSL_SMALL_STACK
     XFREE(W, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+#endif
 
     return 0;
 }
@@ -317,11 +324,16 @@ static int Transform384(Sha384* sha384)
 
     word32 j;
     word64 T[8];
+
+#ifdef CYASSL_SMALL_STACK
     word64* W;
 
     W = (word64*) XMALLOC(sizeof(word64) * 16, NULL, DYNAMIC_TYPE_TMP_BUFFER);
     if (W == NULL)
         return MEMORY_E;
+#else
+    word64 W[16];
+#endif
 
     /* Copy digest to working vars */
     XMEMCPY(T, sha384->digest, sizeof(T));
@@ -360,7 +372,9 @@ static int Transform384(Sha384* sha384)
     XMEMSET(W, 0, sizeof(word64) * 16);
     XMEMSET(T, 0, sizeof(T));
 
+#ifdef CYASSL_SMALL_STACK
     XFREE(W, NULL, DYNAMIC_TYPE_TMP_BUFFER);
+#endif
 
     return 0;
 }