Re: Ada and embedded applications

[Robert A Duff <bobduff@world.std.com>]

"Chris Campbell" <chris.danx@ntlworld.com> writes:

> One poster claimed that Ada was not used in some embedded devices because of
> memory overheads for exception handling.

Sounds like nonsense, but it's not completely clear what that poster
meant.  An exception handler typically costs a small number of words of
space for certain tables.  Even if those tables were huge (not likely),
you don't have to use exception handlers if you don't like.  It's silly
to use C because when using Ada you might be tempted to use an
inefficient feature that C doesn't have at all.

I don't think Ada exception handlers have any *distributed* overhead --
that is, you don't pay anything substantial for the mere existence of
exception handling in the language, if you don't use it.  (Unless you're
talking about combining exception handling and finalization -- but C
doesn't have finalization, so that can't be the issue.)

Perhaps that poster was talking about the space overhead of run-time
checking (array bounds and the like).  That overhead exists, but it's
not all that high, and anyway, pragma Suppress will turn it off.

>...  Claiming it was used in embedded
> devices in industries that had budgets that supported it (e.g. the aerospace
> industry).

That sounds like nonsense, too.  I wouldn't believe it unless some
(current) prices were quoted for comparison.

- Bob