PGI User Forum

[mkcolg]

Hi Craig,

The office is closed for a few days due to the Thanksgiving holiday so I don't have access to WRF. We'll be back on Monday so if you don't mind waiting I'll see what I can determine then.

Thanks,
Mat

[mkcolg]

Hi Craig,


Unfortuntately, I have not been able to recreate the error so don't have a good idea how to fix it. Is it possible for you characterize how is seg faulting?

I'd like you to re-build with "-g -O0 -mp" and re-run. If it still seg faults, run it again in pgdbg or gdb and determine which file and which line it seg faults at. (use the 'where' and 'disasm' commands) If it does not seg fault at -O0, then continue adding higher optimization until it does, i.e. "-O2 -g -mp", "-fast -g -mp", -fastsse -g -mp".

Thanks,
Mat

[Craig Arthur]

Hi Mat,

I started out with the basic ‘-g –O0 –mp’ flag set, and compilation failed with a long list of errors. So I stepped back to the default set (as in those in the configure.wrf I posted previously) and progressively worked back to a point which compilation was successful. The most basic set I could get down to was ‘-g –O0 –mp –byteswapio –Mfree’ (I can’t find any mention of ‘-Mfree’ in the PGF User Guide, so I’m unsure of its effect).

I ran the compiled executable in pgdbg, with pgienv omp on, and I can reach the first OMP command, which is in the subroutine SOLVE_EM.

[mkcolg]

Hi Craig,

Sorry I should have been more clear and said to change just the "FCOPTIM" flag and leave the "FCBASEOPTS" as is. Also, "-Mfree" and "-Mfixed" override the extension (.F, .F90, .f, .f90) to indicate if the file is free or fixed form.

Since 5.1-6 pre-dates Fedora Core 2 and a lot changed with the thread library, the 5.1 version of pgdbg can not step through parallel regions. Again, I should have been more clear. Please run the application without stepping and let it run until it seg faults. Then use the "where" command to see where your at in the program and "diasm" to see what assembly instructions were being executed. Also, please run the exe outside of the debugger to ensure that it does indeed still seg fault at the lower optimization.

Since 5.1-6 does not offically support Fedora Core 2, I'd also like you to try upgrading to 5.2-4 http://www.pgroup.com/support/download_release.php. It is possible that we have an incompatabily between 5.1-6 and Fedora Core 2. Also, the debugger when through a major upgrade. Note that we upgraded your license to 5.2 but you'll need to regenerate your license key in order for the 5.2 compilers to work beyond the 15 day evaluation.

Thanks,
Mat

[Craig Arthur]

Hi Mat,

I've gone through the steps you set out above, and the executable continues to seg fault. Below is one example of the output from the debugger when running wrf.exe compiled with "-g -O0 -mp".