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Re: Strange pthread_self() return value

On Fri, 11 Jun 2021, nia wrote:

The segfault is actually in hwloc, a library used by OpenCL:

Program received signal SIGSEGV, Segmentation fault.
0x0000764e5660a2c8 in pthread_getaffinity_np () from /usr/lib/
(gdb) bt
#0  0x0000764e5660a2c8 in pthread_getaffinity_np () from /usr/lib/
#1  0x0000764e5ec1f86e in hwloc_netbsd_get_thread_cpubind (topology=topology@entry=0x764e60060000,
   tid=0xffffffffffffffff, hwloc_cpuset=hwloc_cpuset@entry=0x764e60078a80, flags=flags@entry=4)
   at topology-netbsd.c:112
#2  0x0000764e5ec1f8d3 in hwloc_netbsd_get_thisthread_cpubind (topology=0x764e60060000,
   hwloc_cpuset=0x764e60078a80, flags=4) at topology-netbsd.c:133

Notice how "tid" is 0xffffffffffffffff. Attempting to set the affinity
of thread "0xffffffffffffffff" obviously fails.

However, this value comes from the return value of pthread_self():

static int
hwloc_netbsd_get_thisthread_cpubind(hwloc_topology_t topology, hwloc_bitmap_t hwloc_cpuset, int flags)
 return hwloc_netbsd_get_thread_cpubind(topology, pthread_self(), hwloc_cpuset, flags);

What's going on?

1. Is `hwloc_thread_t' the same as `pthread_t' when hwloc is compiled
   on NetBSD?

2. Does a `make check' of hwloc on NetBSD pass?


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