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Re: Added error message (for too-large array)
- To: jason_merrill at redhat dot com
- Subject: Re: Added error message (for too-large array)
- From: kenner at vlsi1 dot ultra dot nyu dot edu (Richard Kenner)
- Date: Tue, 25 Sep 01 08:46:54 EDT
- Cc: gcc at gcc dot gnu dot org, law at cygnus dot com
If the size cannot be represented in size_t, it isn't represented
internally in gcc in any useful way; it overflows to some number bearing
little relation to what the user intended.
Right, but TREE_OVERFLOW is set, so we *know* it has overflowed.
It would think the Ada frontend should set TYPE_SIZE itself for such an
ARRAY_TYPE, rather than let the middle-end come up with a meaningless
Why? There's no meaningful value for it, set by anybody. All you can do
with such a type is basically to take a pointer to it or use it to index
an array. Any computation that needs the size is incorrect.
The place you typically see this in Ada is when you are passing things
to C and you want to make a "C-style" array but you are passing
variable-size data. The normal idiom is to make any array whose
bounds are all non-negative integers. But unless each array element
is only one byte long, this will overflow. However, it's fine as long
as nothing needs the size.
But I still don't understand what motiviated this test.