BUILD: makefile: disable threads by default on OpenBSD

As reported by Ilya in issue #725, building with threads on OpenBSD
is broken with gcc:

  include/haproxy/tinfo.h:30: error: thread-local storage not supported for this target

Better stay safe and disable it. Clang seems to support (or emulate)
thread-local, at least it builds. Those willing to experiment can
easily pass USE_THREAD=1.

diff --git a/Makefile b/Makefile
index 04bf8a590cbc66773726382a11813ea4b1159885..7582a88f69f828450073422e02eedabf8950eef6 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -378,7 +378,7 @@ endif
 # OpenBSD 5.7 and above
 ifeq ($(TARGET),openbsd)
   set_target_defaults = $(call default_opts, \
-    USE_POLL USE_TPROXY USE_THREAD USE_KQUEUE USE_ACCEPT4)
+    USE_POLL USE_TPROXY USE_KQUEUE USE_ACCEPT4)
 endif
 
 # NetBSD