HP MLIB for PA-RISC and Itanium HP-UX Version 9.5.6 Release Note

Compatibility Information

For example, the following Fortran code makes parallel calls to subprogram DAXPY:

C$OMP PARALLEL DO

DO 10 J=1, N

CALL DAXPY (N-I,A(I,J),A(I+1,I),1,A(I+1,J),1)

10 CONTINUE

C$OMP END PARALLEL DO

While optimizing a parallel program, you may want to make parallel calls to an MLIB

subprogram to execute independent operations where the call statements are not in a loop.

You can use the OpenMP compiler directives SECTIONS, SECTION, and END SECTIONS to tell

the compiler to parallelize such code.

• To enable MLIB SMP parallelism, link as follows:

% f90 +O3 +Oparallel

[options] file

...[-lveclib|-llapack|-lsolvers]

% cc +O3 +Oopenmp

[options] file

...[-lveclib|-llapack|-lsolvers] -lcl -lm

% aCC +Oparallel

[options] file ...

[-lveclib|-llapack|-lsolvers] -lcl -lm

User Resource Limits

Users may encounter failures caused by resource limits. This failure is typically a

segmentation violation caused by exceeding the resource limit for stack size. This arises when

large arrays are placed on the stack; for example by C language automatic storage class

variables (e.g. variables declared within a block).

HP MLIB may use up to 8 MB of stack space in addition to the application’s requirements.

You may want to reset your stacksize.

The resource limits can be changed by means of the ulimit command for Bourne-like shells or

the limit command for C-like shells. For example:

% ulimit -s unlimited

% limit stacksize unlimited