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RE: What to remove after tree-ssa is merged?


Hi,

On Wed, 4 Feb 2004, S. Bosscher wrote:

> But since Ada is lagging, like, three years on the rest of GCC,
> and nobody so far has explained what PLACEHOLDER_EXPR is for

It's not that Kenner is totally wrong with documentation ;-)
PLACEHOLDER_EXPR is described in tree.def and is used for types whose 
layout/content changes with values of members in such type.  Like 
pseudo-type:

  type T {
    switch enum BLA discriminator {
      VARIANT_1 : int i; char c;
      VARIANT_2 : char d; long l;
    }
  }

Here the offset of T.c (or even it's existance) depends on the value of 
T.discriminator.


Ciao,
Michael.


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