Re: [Tinycc-devel] VLAs broken on mob branch

[Pip Cet]

On Tue, Apr 28, 2015 at 8:53 AM, Sergey Korshunoff <address@hidden> wrote:
> I removed all calls to vla_sp_save() keeping these only in
> decl_initializer(). All tests passed.

That's not saying very much—we don't have good test coverage for VLAs.
I think we can get away with simplifying the code a lot, but I'd
rather leave it in case someone wants to go back to implementing the
lazy stack pointer saving optimization.

In particular, I don't know precisely what the rules are for combining
alloca() and VLAs. I don't think you're allowed to do so in the same
scope, but I'm not at all confident our code works if we do both in
the same function.

That said, our VLA code can be made a lot simpler (simple enough for
even me to understand it) by giving up on the optimization idea, which
is very tempting. There's a patch to do that attached, feel free to
test and commit it if you like. (It passes all the tests, at least).


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tcc-simple-vlas.diff
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