diff --git a/groestl.c b/groestl.c
index e827278..de736a0 100644
--- a/groestl.c
+++ b/groestl.c
@@ -17,7 +17,6 @@ void groestl_hash(const char* input, char* output, uint32_t len)
     sph_groestl512(&ctx_groestl, input, len);
     sph_groestl512_close(&ctx_groestl, hash1);
     
-    sph_groestl512_init(&ctx_groestl);
     sph_groestl512(&ctx_groestl, hash1, 64);
     sph_groestl512_close(&ctx_groestl, hash2);
     
@@ -39,7 +38,7 @@ void groestl_myriad_hash(const char* input, char* output, uint32_t len)
     SHA256_CTX ctx_sha256;
     SHA256_Init(&ctx_sha256);
     SHA256_Update(&ctx_sha256, temp, 64);
-    SHA256_Final(output, &ctx_sha256);
+    SHA256_Final((unsigned char*) output, &ctx_sha256);
     
     free(temp);
 }
diff --git a/quark.c b/quark.c
index 498e08f..db85941 100644
--- a/quark.c
+++ b/quark.c
@@ -114,7 +114,6 @@ void quark_hash(const char* input, char* output, uint32_t len)
     sph_jh512_context        ctx_jh;
     sph_keccak512_context    ctx_keccak;
     sph_skein512_context     ctx_skein;
-    static unsigned char pblank[1];
 
     uint32_t mask = 8;
     uint32_t zero = 0;
diff --git a/scrypt.c b/scrypt.c
index 32139ff..cf71280 100644
--- a/scrypt.c
+++ b/scrypt.c
@@ -223,7 +223,7 @@ smix(uint8_t * B, size_t r, uint64_t N, uint32_t * V, uint32_t * XY)
 /* cpu and memory intensive function to transform a 80 byte buffer into a 32 byte output
    scratchpad size needs to be at least 63 + (128 * r * p) + (256 * r + 64) + (128 * r * N) bytes
  */
-void scrypt_1024_1_1_256_sp(const char* input, char* output, char* scratchpad, size_t len)
+void scrypt_1024_1_1_256_sp(const char* input, char* output, char* scratchpad, uint32_t len)
 {
 	uint8_t * B;
 	uint32_t * V;
@@ -248,10 +248,10 @@ void scrypt_1024_1_1_256_sp(const char* input, char* output, char* scratchpad, s
 	}
 
 	/* 5: DK <-- PBKDF2(P, B, 1, dkLen) */
-	PBKDF2_SHA256((const uint8_t*)input, 80, B, p * 128 * r, 1, (uint8_t*)output, 32);
+	PBKDF2_SHA256((const uint8_t*)input, len, B, p * 128 * r, 1, (uint8_t*)output, 32);
 }
 
-void scrypt_1024_1_1_256(const char* input, char* output, size_t len)
+void scrypt_1024_1_1_256(const char* input, char* output, uint32_t len)
 {
 	char scratchpad[131583];
 	scrypt_1024_1_1_256_sp(input, output, scratchpad, len);
diff --git a/scrypt.h b/scrypt.h
index 1a4ed05..645fbab 100644
--- a/scrypt.h
+++ b/scrypt.h
@@ -1,10 +1,10 @@
 #ifndef SCRYPT_H
 #define SCRYPT_H
 
-#include <stddef.h>
+#include <stdint.h>
 
-void scrypt_1024_1_1_256(const char* input, char* output, size_t len);
-void scrypt_1024_1_1_256_sp(const char* input, char* output, char* scratchpad, size_t len);
+void scrypt_1024_1_1_256(const char* input, char* output, uint32_t len);
+void scrypt_1024_1_1_256_sp(const char* input, char* output, char* scratchpad, uint32_t len);
 #define  scrypt_scratchpad_size 131583;
 
 #endif
\ No newline at end of file
diff --git a/scryptn.c b/scryptn.c
index 9c89d1c..cef7fca 100644
--- a/scryptn.c
+++ b/scryptn.c
@@ -217,7 +217,7 @@ smix(uint8_t * B, size_t r, uint64_t N, uint32_t * V, uint32_t * XY)
 /* cpu and memory intensive function to transform a 80 byte buffer into a 32 byte output
    scratchpad size needs to be at least 63 + (128 * r * p) + (256 * r + 64) + (128 * r * N) bytes
  */
-void scrypt_N_1_1_256_sp(const char* input, char* output, char* scratchpad, uint32_t N, size_t len)
+void scrypt_N_1_1_256_sp(const char* input, char* output, char* scratchpad, uint32_t N, uint32_t len)
 {
 	uint8_t * B;
 	uint32_t * V;
@@ -242,10 +242,10 @@ void scrypt_N_1_1_256_sp(const char* input, char* output, char* scratchpad, uint
 	}
 
 	/* 5: DK <-- PBKDF2(P, B, 1, dkLen) */
-	PBKDF2_SHA256((const uint8_t*)input, 80, B, p * 128 * r, 1, (uint8_t*)output, 32);
+	PBKDF2_SHA256((const uint8_t*)input, len, B, p * 128 * r, 1, (uint8_t*)output, 32);
 }
 
-void scrypt_N_1_1_256(const char* input, char* output, uint32_t N, size_t len)
+void scrypt_N_1_1_256(const char* input, char* output, uint32_t N, uint32_t len)
 {
 	//char scratchpad[131583];
     char *scratchpad;
diff --git a/scryptn.h b/scryptn.h
index 3e754fa..3357b95 100644
--- a/scryptn.h
+++ b/scryptn.h
@@ -5,8 +5,8 @@
 extern "C" {
 #endif
 
-void scrypt_N_1_1_256(const char* input, char* output, uint32_t N, size_t len);
-void scrypt_N_1_1_256_sp(const char* input, char* output, char* scratchpad, uint32_t N, size_t len);
+void scrypt_N_1_1_256(const char* input, char* output, uint32_t N, uint32_t len);
+void scrypt_N_1_1_256_sp(const char* input, char* output, char* scratchpad, uint32_t N, uint32_t len);
 //const int scrypt_scratchpad_size = 131583;
 
 #ifdef __cplusplus
diff --git a/sha256.h b/sha256.h
index ddb4ba6..5858f65 100644
--- a/sha256.h
+++ b/sha256.h
@@ -437,4 +437,4 @@ PBKDF2_SHA256(const uint8_t * passwd, size_t passwdlen, const uint8_t * salt,
 	/* Clean PShctx, since we never called _Final on it. */
 	memset(&PShctx, 0, sizeof(HMAC_SHA256_CTX));
 }
-#endif
\ No newline at end of file
+#endif
diff --git a/sha3/sph_groestl.c b/sha3/sph_groestl.c
index 928bc41..91f75d3 100644
--- a/sha3/sph_groestl.c
+++ b/sha3/sph_groestl.c
@@ -2813,7 +2813,6 @@ static void
 groestl_small_close(sph_groestl_small_context *sc,
 	unsigned ub, unsigned n, void *dst, size_t out_len)
 {
-	unsigned char *buf;
 	unsigned char pad[72];
 	size_t u, ptr, pad_len;
 #if SPH_64
@@ -2824,7 +2823,6 @@ groestl_small_close(sph_groestl_small_context *sc,
 	unsigned z;
 	DECL_STATE_SMALL
 
-	buf = sc->buf;
 	ptr = sc->ptr;
 	z = 0x80 >> n;
 	pad[0] = ((ub & -z) | z) & 0xFF;
@@ -2949,7 +2947,6 @@ static void
 groestl_big_close(sph_groestl_big_context *sc,
 	unsigned ub, unsigned n, void *dst, size_t out_len)
 {
-	unsigned char *buf;
 	unsigned char pad[136];
 	size_t ptr, pad_len, u;
 #if SPH_64
@@ -2960,7 +2957,6 @@ groestl_big_close(sph_groestl_big_context *sc,
 	unsigned z;
 	DECL_STATE_BIG
 
-	buf = sc->buf;
 	ptr = sc->ptr;
 	z = 0x80 >> n;
 	pad[0] = ((ub & -z) | z) & 0xFF;
diff --git a/skein.c b/skein.c
index 38fba74..4676a87 100644
--- a/skein.c
+++ b/skein.c
@@ -21,7 +21,7 @@ void skein_hash(const char* input, char* output, uint32_t len)
     SHA256_CTX ctx_sha256;
     SHA256_Init(&ctx_sha256);
     SHA256_Update(&ctx_sha256, temp, 64);
-    SHA256_Final(output, &ctx_sha256);
+    SHA256_Final((unsigned char*) output, &ctx_sha256);
     
     free(temp);
 }