diff --git a/library/md_wrap.c b/library/md_wrap.c
index 62110ce..ea0c1d2 100644
--- a/library/md_wrap.c
+++ b/library/md_wrap.c
@@ -396,7 +396,7 @@
 static void * ripemd160_ctx_alloc( void )
 {
     ripemd160_context *ctx;
-    ctx = (ripemd160_context *) polarssl_malloc( sizeof( ripemd160_context ) );
+    ctx = polarssl_malloc( sizeof( ripemd160_context ) );
 
     if( ctx == NULL )
         return( NULL );
@@ -492,7 +492,7 @@
 static void * sha1_ctx_alloc( void )
 {
     sha1_context *ctx;
-    ctx = (sha1_context *) polarssl_malloc( sizeof( sha1_context ) );
+    ctx = polarssl_malloc( sizeof( sha1_context ) );
 
     if( ctx == NULL )
         return( NULL );
@@ -701,7 +701,7 @@
 static void * sha256_ctx_alloc( void )
 {
     sha256_context *ctx;
-    ctx = (sha256_context *) polarssl_malloc( sizeof( sha256_context ) );
+    ctx = polarssl_malloc( sizeof( sha256_context ) );
 
     if( ctx == NULL )
         return( NULL );
@@ -907,7 +907,7 @@
 static void * sha512_ctx_alloc( void )
 {
     sha512_context *ctx;
-    ctx = (sha512_context *) polarssl_malloc( sizeof( sha512_context ) );
+    ctx = polarssl_malloc( sizeof( sha512_context ) );
 
     if( ctx == NULL )
         return( NULL );