No -O3 in ports builds.

--- rpython/translator/platform/openbsd.py.orig	Sun Jul 13 16:44:39 2014
+++ rpython/translator/platform/openbsd.py	Sun Jul 13 16:45:46 2014
@@ -9,7 +9,7 @@ class OpenBSD(BSD):
     name = "openbsd"
 
     link_flags = os.environ.get("LDFLAGS", "").split() + ['-pthread']
-    cflags = ['-O3', '-pthread', '-fomit-frame-pointer', '-D_BSD_SOURCE'
+    cflags = ['-pthread', '-fomit-frame-pointer', '-D_BSD_SOURCE'
              ] + os.environ.get("CFLAGS", "").split()
 
     def _libs(self, libraries):
