$OpenBSD$
--- src/m_alloc.cpp.orig	Sat Jan 30 19:27:35 2016
+++ src/m_alloc.cpp	Sun Jan 31 01:46:37 2016
@@ -52,14 +52,14 @@
 #endif
 #if defined(__APPLE__)
 #define _msize(p)				malloc_size(p)
-#elif defined(__sun)
+#elif defined(__sun) || defined(__OpenBSD__)
 #define _msize(p)				(*((size_t*)(p)-1))
 #elif !defined(_WIN32)
 #define _msize(p)				malloc_usable_size(p)	// from glibc/FreeBSD
 #endif
 
 #ifndef _DEBUG
-#if !defined(__sun)
+#if !(defined(__sun) || defined(__OpenBSD__))
 void *M_Malloc(size_t size)
 {
 	void *block = malloc(size);
@@ -129,7 +129,7 @@ void *M_Realloc(void *memblock, size_t size)
 #include <crtdbg.h>
 #endif
 
-#if !defined(__sun)
+#if !(defined(__sun) || defined(__OpenBSD__))
 void *M_Malloc_Dbg(size_t size, const char *file, int lineno)
 {
 	void *block = _malloc_dbg(size, _NORMAL_BLOCK, file, lineno);
@@ -197,7 +197,7 @@ void *M_Realloc_Dbg(void *memblock, size_t size, const
 #endif
 #endif
 
-#if !defined(__sun)
+#if !(defined(__sun) || defined(__OpenBSD__))
 void M_Free (void *block)
 {
 	if (block != NULL)