Index: deps/v8/src/base/platform/platform-posix.cc
--- deps/v8/src/base/platform/platform-posix.cc.orig
+++ deps/v8/src/base/platform/platform-posix.cc
@@ -1266,7 +1266,7 @@ bool Thread::Start() {
   if (result != 0) return false;
   size_t stack_size = stack_size_;
   if (stack_size == 0) {
-#if V8_OS_DARWIN
+#if V8_OS_DARWIN || V8_OS_OPENBSD
     // Default on Mac OS X is 512kB -- bump up to 1MB
     stack_size = 1 * 1024 * 1024;
 #elif V8_OS_AIX
