Re: GNAT compiler switches and optimization

[Robert A Duff <bobduff@shell01.TheWorld.com>]

Warner BRUNS <Warner.Bruns@cern.ch> writes:

> A problem with Ada is that the memory layout of multidimensional arrays
> is not specified in the standard. If you want to have the same memory
> layout for all Ada compilers, you have to specify that a multimensional
> array should follow the convention of a foreign language, eg. Fortran.
>    TYPE DefReal IS DIGITS 12;
>    TYPE DefReal2D IS ARRAY(Integer RANGE <>,
>                            Integer RANGE <>) OF DefReal;
>    PRAGMA CONVENTION (Fortran, DefReal2D);

In practise, you can count on the fact that all Ada compilers will
choose row-major order, unless you ask for column-major via the above
pragma, even though the RM does not say so.

> There is something missing in the Ada standard.

Perhaps.

- Bob