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From: Ralf Wildenhues (Ralf.Wildenhues_at_[hidden])
Date: 2006-04-10 04:31:45


Apologies for a slightly off-topic (Autoconf-related) question.

I believe OpenMPI deals with Fortran implementations where integer
types contain internal padding (i.e., not all bits are used for the
value); at least I read the configure macros this way.

Is padding in C types a practical issue as well? Say, a 'short' with a
maximum value of 32767 but 32 or 64 bits storage size?

The only system we found that exhibits this was a Cray Y-MP from the
cray-cyber museum (it's accessible and usable), but we don't know of
more modern systems that do this.

Background: there is discussion[1] over a macro to compute such ranges,
fit also for cross compilation, but we're unsure about its practical
value. I figured the readers here may have more such experience.

Cheers, and apologies again,
Ralf

[1] http://thread.gmane.org/gmane.comp.sysutils.autoconf.patches/2745/focus=3117