Fix copy/paste error and compiler warnings

contracts/eosio.bios/eosio.bios.hpp

@@ -31,7 +31,7 @@ namespace eosio {
             size_t size = action_data_size();
             char* buffer = (char*)( max_stack_buffer_size < size ? malloc(size) : alloca(size) );
             read_action_data( buffer, size );
-            set_proposed_producers(buffer, sizeof(buffer));
+            set_proposed_producers(buffer, size);
          }
 
          void reqauth( action_name from ) {

contracts/eosiolib/action.hpp

@@ -48,7 +48,7 @@ namespace eosio {
       size_t size = action_data_size();
       char* buffer = (char*)( max_stack_buffer_size < size ? malloc(size) : alloca(size) );
       read_action_data( buffer, size );
-      return unpack<T>( buffer, sizeof(buffer) );
+      return unpack<T>( buffer, size );
    }
 
    using ::require_auth;

contracts/eosiolib/transaction.hpp

@@ -77,12 +77,13 @@ namespace eosio {
     */
    inline action get_action( uint32_t type, uint32_t index ) {
       constexpr size_t max_stack_buffer_size = 128;
-      auto size = ::get_action(type, index, nullptr, 0);
-      eosio_assert( size > 0, "get_action size failed" );
+      int s = ::get_action( type, index, nullptr, 0 );
+      eosio_assert( s > 0, "get_action size failed" );
+      size_t size = static_cast<size_t>(s);
       char* buffer = (char*)( max_stack_buffer_size < size ? malloc(size) : alloca(size) );
-      auto size2 = ::get_action(type, index, buffer, static_cast<size_t>(size) );
-      eosio_assert( size == size2, "get_action failed" );
-      return eosio::unpack<eosio::action>(buffer, static_cast<size_t>(size));
+      auto size2 = ::get_action( type, index, buffer, size );
+      eosio_assert( size == static_cast<size_t>(size2), "get_action failed" );
+      return eosio::unpack<eosio::action>( buffer, size );
    }
 
    ///@} transactioncpp api