Debugger cannot access variables in common block on Mac OS

[Nicolao]

I have a number of variables placed in COMMON blocks. With Mac OS X and ifort compiler, when I try to access them from inside the debugger (either gdb or idb), the value of the variables is either incorrect (seems random) or I get a message which says that the memory location cannot be accessed.

On Linux and ifort, I have no problem.

Anybody knows how can I solve this problem on Mac OS X? I tried many ifort options, but nothing worked. Obviously I am using no optimization and debug infos (-O0 -g flags).

- On Mac OS 10.4.9 I am using: ifort 9.1.039, idb 9.1-28 and GNU gdb 6.3.50-20050815 (Apple version gdb-563)

- On Linux Fedora Core 6: ifort 9.0, idb 9.0 and GNU gdb Red Hat Linux (6.5-15.fc6rh)

[BTW, This problem reminds me of the old one which was present on Linux and g77: for that compiler a -fdebug-kludge flag was included, and it seemed to solve the problem.]

[Steven_L_Intel1]

First, did you see the text in the Release Notes saying that you have to preserve the .o files? Please see if that helps. If not, please file a report with Intel Premier Support.

[Nicolao]

Steve, thanks for the prompt reply.

Yes, the object file are preserved. This problem with the COMMON blocks and EQUIVALENCE statements is a longstading one (at least under g77). I am surprised that it is not yet solved for the Mac OS version. I will follow your suggestion and send a report to Intel Premier Support.

[Steven_L_Intel1]

Each of the three platforms we support does debugging info a different way. What we find is that the available support in the debugging interface is designed for C and has to be "coerced" to support Fortran features such as COMMON and EQUIVALENCE (and modules...) Please do report this so that we see what is wrong.