From adf3ebe89196637592337108f4e8b33dfa10f3ef Mon Sep 17 00:00:00 2001
From: Ivan Maidanski <ivmai@mail.ru>
Date: Tue, 14 Nov 2023 20:08:29 +0300
Subject: [PATCH] Fix lock assertion violation in GC_try_to_collect_inner on OS
 X (fix of commit b7b1004a2)

Issue #583 (bdwgc).

This happens only in the multi-threaded collector with assertions on
and malloc redirection if GC_enable_incremental() is called.

* include/private/gc_priv.h [MPROTECT_VDB && DARWIN]: Include pthread.h
(wrapped into EXTERN_C_END/BEGIN).
* include/private/gc_priv.h [MPROTECT_VDB && DARWIN && THREADS]
(GC_inner_pthread_create): Declare (as GC_INNER function).
* include/private/gc_priv.h [MPROTECT_VDB && DARWIN && !THREADS]
(GC_inner_pthread_create): Define as macro (redirecting to
pthread_create).
* os_dep.c [MPROTECT_VDB && DARWIN]: Do not include pthread.h.
* os_dep.c [MPROTECT_VDB && DARWIN] (pthread_create): Do not undefine.
* os_dep.c [MPROTECT_VDB && DARWIN] (GC_dirty_init): Call
GC_inner_pthread_create() instead of pthread_create().
* pthread_support.c [MPROTECT_VDB && DARWIN] (GC_inner_pthread_create):
Define function (call INIT_REAL_SYMS() and REAL_FUNC(pthread_create)).
---
 include/private/gc_priv.h | 13 +++++++++++++
 os_dep.c                  |  6 ++----
 pthread_support.c         | 10 ++++++++++
 3 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/include/private/gc_priv.h b/include/private/gc_priv.h
index de25d492e..5c39446d7 100644
--- a/include/private/gc_priv.h
+++ b/include/private/gc_priv.h
@@ -2588,6 +2588,19 @@ GC_EXTERN GC_bool GC_print_back_height;
 #   endif
 # endif /* CAN_HANDLE_FORK */
 
+# if defined(MPROTECT_VDB) && defined(DARWIN)
+    EXTERN_C_END
+#   include <pthread.h>
+    EXTERN_C_BEGIN
+#   ifdef THREADS
+      GC_INNER int GC_inner_pthread_create(pthread_t *t,
+                                GC_PTHREAD_CREATE_CONST pthread_attr_t *a,
+                                void *(*fn)(void *), void *arg);
+#   else
+#     define GC_inner_pthread_create pthread_create
+#   endif
+# endif /* MPROTECT_VDB && DARWIN */
+
   GC_INNER GC_bool GC_dirty_init(void);
                 /* Returns true if dirty bits are maintained (otherwise */
                 /* it is OK to be called again if the client invokes    */
diff --git a/os_dep.c b/os_dep.c
index 5a4a652e3..a2002831e 100644
--- a/os_dep.c
+++ b/os_dep.c
@@ -4393,7 +4393,6 @@ GC_INNER GC_bool GC_dirty_init(void)
 #include <mach/mach_error.h>
 #include <mach/exception.h>
 #include <mach/task.h>
-#include <pthread.h>
 
 EXTERN_C_BEGIN
 
@@ -4767,9 +4766,8 @@ GC_INNER GC_bool GC_dirty_init(void)
   if (pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) != 0)
     ABORT("pthread_attr_setdetachedstate failed");
 
-# undef pthread_create
-  /* This will call the real pthread function, not our wrapper */
-  if (pthread_create(&thread, &attr, GC_mprotect_thread, NULL) != 0)
+  /* This will call the real pthread function, not our wrapper. */
+  if (GC_inner_pthread_create(&thread, &attr, GC_mprotect_thread, NULL) != 0)
     ABORT("pthread_create failed");
   (void)pthread_attr_destroy(&attr);
 
diff --git a/pthread_support.c b/pthread_support.c
index 4421fedcd..cd2ba2dbc 100644
--- a/pthread_support.c
+++ b/pthread_support.c
@@ -260,6 +260,16 @@
 
 static GC_bool parallel_initialized = FALSE;
 
+#if defined(MPROTECT_VDB) && defined(DARWIN)
+  GC_INNER int GC_inner_pthread_create(pthread_t *t,
+                                GC_PTHREAD_CREATE_CONST pthread_attr_t *a,
+                                void *(*fn)(void *), void *arg)
+  {
+    INIT_REAL_SYMS();
+    return REAL_FUNC(pthread_create)(t, a, fn, arg);
+  }
+#endif
+
 #ifndef GC_ALWAYS_MULTITHREADED
   GC_INNER GC_bool GC_need_to_lock = FALSE;
 #endif