$OpenBSD: patch-src_runtime_cgo_gcc_openbsd_amd64_c,v 1.1 2016/05/16 13:50:02 jsing Exp $
--- src/runtime/cgo/gcc_openbsd_amd64.c.orig	Thu Feb 18 07:35:22 2016
+++ src/runtime/cgo/gcc_openbsd_amd64.c	Sat May 14 02:21:07 2016
@@ -5,8 +5,6 @@
 // +build cgo
 
 #include <sys/types.h>
-#include <dlfcn.h>
-#include <errno.h>
 #include <pthread.h>
 #include <signal.h>
 #include <string.h>
@@ -15,102 +13,6 @@
 static void* threadentry(void*);
 static void (*setg_gcc)(void*);
 
-// TCB_SIZE is sizeof(struct thread_control_block),
-// as defined in /usr/src/lib/librthread/tcb.h
-#define TCB_SIZE (4 * sizeof(void *))
-#define TLS_SIZE (2 * sizeof(void *))
-
-void *__get_tcb(void);
-void __set_tcb(void *);
-
-static int (*sys_pthread_create)(pthread_t *thread, const pthread_attr_t *attr,
-	void *(*start_routine)(void *), void *arg);
-
-struct thread_args {
-	void *(*func)(void *);
-	void *arg;
-};
-
-static void
-tcb_fixup(int mainthread)
-{
-	void *newtcb, *oldtcb;
-
-	// The OpenBSD ld.so(1) does not currently support PT_TLS. As a result,
-	// we need to allocate our own TLS space while preserving the existing
-	// TCB that has been setup via librthread.
-
-	newtcb = malloc(TCB_SIZE + TLS_SIZE);
-	if(newtcb == NULL)
-		abort();
-
-	// The signal trampoline expects the TLS slots to be zeroed.
-	bzero(newtcb, TLS_SIZE);
-
-	oldtcb = __get_tcb();
-	bcopy(oldtcb, newtcb + TLS_SIZE, TCB_SIZE);
-	__set_tcb(newtcb + TLS_SIZE);
-
-	// NOTE(jsing, minux): we can't free oldtcb without causing double-free
-	// problem. so newtcb will be memory leaks. Get rid of this when OpenBSD
-	// has proper support for PT_TLS.
-}
-
-static void *
-thread_start_wrapper(void *arg)
-{
-	struct thread_args args = *(struct thread_args *)arg;
-
-	free(arg);
-	tcb_fixup(0);
-
-	return args.func(args.arg);
-}
-
-static void init_pthread_wrapper(void) {
-	void *handle;
-
-	// Locate symbol for the system pthread_create function.
-	handle = dlopen("libpthread.so", RTLD_LAZY);
-	if(handle == NULL) {
-		fprintf(stderr, "runtime/cgo: dlopen failed to load libpthread: %s\n", dlerror());
-		abort();
-	}
-	sys_pthread_create = dlsym(handle, "pthread_create");
-	if(sys_pthread_create == NULL) {
-		fprintf(stderr, "runtime/cgo: dlsym failed to find pthread_create: %s\n", dlerror());
-		abort();
-	}
-	dlclose(handle);
-}
-
-static pthread_once_t init_pthread_wrapper_once = PTHREAD_ONCE_INIT;
-
-int
-pthread_create(pthread_t *thread, const pthread_attr_t *attr,
-	void *(*start_routine)(void *), void *arg)
-{
-	struct thread_args *p;
-
-	// we must initialize our wrapper in pthread_create, because it is valid to call
-	// pthread_create in a static constructor, and in fact, our test for issue 9456
-	// does just that.
-	if(pthread_once(&init_pthread_wrapper_once, init_pthread_wrapper) != 0) {
-		fprintf(stderr, "runtime/cgo: failed to initialize pthread_create wrapper\n");
-		abort();
-	}
-
-	p = malloc(sizeof(*p));
-	if(p == NULL) {
-		errno = ENOMEM;
-		return -1;
-	}
-	p->func = start_routine;
-	p->arg = arg;
-
-	return sys_pthread_create(thread, attr, thread_start_wrapper, p);
-}
-
 void
 x_cgo_init(G *g, void (*setg)(void*))
 {
@@ -122,13 +24,6 @@ x_cgo_init(G *g, void (*setg)(void*))
 	pthread_attr_getstacksize(&attr, &size);
 	g->stacklo = (uintptr)&attr - size + 4096;
 	pthread_attr_destroy(&attr);
-
-	if(pthread_once(&init_pthread_wrapper_once, init_pthread_wrapper) != 0) {
-		fprintf(stderr, "runtime/cgo: failed to initialize pthread_create wrapper\n");
-		abort();
-	}
-
-	tcb_fixup(1);
 }
 
 
@@ -149,7 +44,7 @@ _cgo_sys_thread_start(ThreadStart *ts)
 
 	// Leave stacklo=0 and set stackhi=size; mstack will do the rest.
 	ts->g->stackhi = size;
-	err = sys_pthread_create(&p, &attr, threadentry, ts);
+	err = pthread_create(&p, &attr, threadentry, ts);
 
 	pthread_sigmask(SIG_SETMASK, &oset, nil);
 
@@ -163,8 +58,6 @@ static void*
 threadentry(void *v)
 {
 	ThreadStart ts;
-
-	tcb_fixup(0);
 
 	ts = *(ThreadStart*)v;
 	free(v);
