Merge pull request #3713 from mdionisio/useless_ceil

avoid to use std::ceil

RELICENSE/mdionisio.md

+# Permission to Relicense under MPLv2
+
+This is a statement by Thomas M. DuBuisson
+that grants permission to relicense its copyrights in the libzmq C++
+library (ZeroMQ) under the Mozilla Public License v2 (MPLv2).
+
+A portion of the commits made by the Github handle "mdionisio", with
+commit author "Michele Dionisio", are copyright of Michele Dionisio.
+This document hereby grants the libzmq project team to relicense libzmq,
+including all past, present and future contributions of the author listed above.
+
+Michele Dionisio
+2019/07/09

src/decoder_allocators.cpp

@@ -30,8 +30,6 @@
 #include "precompiled.hpp"
 #include "decoder_allocators.hpp"
 
-#include <cmath>
-
 #include "msg.hpp"
 
 zmq::shared_message_memory_allocator::shared_message_memory_allocator (
@@ -40,9 +38,7 @@ zmq::shared_message_memory_allocator::shared_message_memory_allocator (
     _buf_size (0),
     _max_size (bufsize_),
     _msg_content (NULL),
-    _max_counters (static_cast<size_t> (
-      std::ceil (static_cast<double> (_max_size)
-                 / static_cast<double> (msg_t::max_vsm_size))))
+    _max_counters ((_max_size + msg_t::max_vsm_size - 1) / msg_t::max_vsm_size)
 {
 }