$OpenBSD: patch-base_files_memory_mapped_file_posix_cc,v 1.1 2017/10/28 07:36:00 robert Exp $

Index: base/files/memory_mapped_file_posix.cc
--- base/files/memory_mapped_file_posix.cc.orig
+++ base/files/memory_mapped_file_posix.cc
@@ -116,7 +116,7 @@ bool MemoryMappedFile::MapFileRegionToMemory(
 
 #if defined(OS_ANDROID) && __ANDROID_API__ < 21
       do_manual_extension = true;
-#elif !defined(OS_MACOSX)
+#elif !defined(OS_MACOSX) && !defined(OS_BSD)
       if (posix_fallocate(file_.GetPlatformFile(), region.offset,
                           region.size) != 0) {
         DPLOG(ERROR) << "posix_fallocate " << file_.GetPlatformFile();
