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Re: [PATCH, PR50527] Don't assume alignment of vla-related allocas.


On 10/04/2011 01:17 PM, Tom de Vries wrote:
> In general, to fold vlas (which are lowered to allocas) to normal declarations,
> if the alloca argument is constant.

Ah.  Ok, I suppose.  How often are you seeing this happening?  I can imagine
a few instances via inlining, but even there not so much...

> Any guidance on what to do if we have to expand the __builtin_alloca_with_align
> to a function call, specifically, with the second argument? This is currently
> handled like this, which is not very nice:

Don't do anything special.  Just let it fall through as with alloca.  This should
never happen, except for stupid user tricks like -fno-builtin-alloca_with_align.
And if the user does that, they get what they deserve wrt needing to implement
that function in their runtime.


r~


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