Getting segfault when using HPX mutexes and condition variables

[light2802]

On replacing the pthread mutex and condition variable calls with hpxc the program leads to a segfault and race conditions (See PR #2 for code)

See following output (only a small part) of the hello world example with OMP_NUM_THREADS=100

Hello World, from thread: 0
Hello World, from thread: 29
Hello World, from thread: 87
Hello World, from thread: 78
Hello World, from thread: 90
Hello World, from thread: 3
Hello World, from thread: 77
Hello World, from thread: 79
Hello World, from thread: 54
Hello World, from thread: 6
Hello World, from thread: 84
Hello World, from thread: 86
Hello World, from thread: 76
Hello World, from thread: 53
Hello World, from thread: 85
Hello World, from thread: 52
Hello World, from thread: 30
Hello World, from thread: 32
Hello World, from thread: 89
Hello World, from thread: 87
Hello World, from thread: 79
Hello World, from thread: 83
Hello World, from thread: 6
Hello World, from thread: 86
Hello World, from thread: 76
Hello World, from thread: 53
Hello World, from thread: 88
Hello World, from thread: 85
Hello World, from thread: 3

See that some thread ids are repeated (like 3)

[light2802]

We also get an occasional error message from openmp runtime (when OMP_NUM_THREADS is large, ~100)

Assertion failure at kmp_runtime.cpp(8012): KMP_MASTER_GTID(gtid).                                                 
OMP: Error #13: Assertion failure at kmp_runtime.cpp(8012).                                                        
OMP: Hint Please submit a bug report with this message, compile and run commands used, and machine configuration info including native compiler and operating system versions. Faster response will be obtained by including all program sources. For information on submitting this issue, please see https://bugs.llvm.org/.                             
Assertion failure at kmp_runtime.cpp(6922): temp_reg_status_file_name.                                             
OMP: Error #13: Assertion failure at kmp_runtime.cpp(6922).                                                        
OMP: Hint Please submit a bug report with this message, compile and run commands used, and machine configuration info including native compiler and operating system versions. Faster response will be obtained by including all program sources. For information on submitting this issue, please see https://bugs.llvm.org/.                             
^CSegmentation fault (core dumped

Another observation is that the code is very very slow compared to the original OpenMP code. Check the hello world example for this.

[rtohid]

@Pansysk75 when you get the chance, can you please look into this?

[Pansysk75]

@Pansysk75 when you get the chance, can you please look into this?

Ah thanks for the mention, will do!

[Pansysk75]

The two PRs above seem to fix both the segfaults and the race-condition-like behaviour mentioned here. The common case works for me, although I didn't have time to stress-test it yet.