Segfault in OpenMP program

I have a fortran program which I’m trying to run using OpenMP parallel directives. When I compile the program with -mp -r8 -mcmodel=medium -O3 it segfaults at the first OMP worksharing directive. If I run with one thread there is no problem. Debugging gives the following:

(gdb) run
Starting program: /data1/scamicha/INDIRECTPOT/MODEDECOMPOSE/test/decompose
[Thread debugging using libthread_db enabled]
[New Thread 47510998064320 (LWP 14037)]
Your time is 12.03332300130014
[New Thread 1082132800 (LWP 14044)]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1082132800 (LWP 14044)]
0x00002b3603033356 in _mp_slave () from /opt/pgi/linux86-64/8.0-6/libso/

Am I not passing the right compiler flags or something? It seems that this must be something painfully obvious that I’m missing. This code works fine with other compilers, Intel, Pathscale, GNU

Hi Scott,

It could any number of things but I would first try setting your environment’s stack size to ‘unlimited’. Next try compiling without “-r8” or “-mcmodel=medium”.

If neither of these work, please send a report to PGI customer support at and include an example so they can recreate the problem.