Re: [3.4 PATCH] PR 17078: Problems in expand_unreachable_stmt

[Mark Mitchell <mark at codesourcery dot com>]

Roger Sayle wrote:

> I was considering committing this patch directly, but on second
> thoughts (i) the changes are technically to the C front-end not
> the middle-end, (ii) the patch is against the gcc-3_4-branch and
> (iii) how this fixes the problem might no be immediately obvious.
>  
>
> PR rtl-optimization/17078 is a wrong-code bug on the gcc 3.4
> branch introduced by Geoff Keating's patch to limit the recursion
> depth of expand_unreachable_stmt to avoid problems with Darwin's
> limited stack size.
>
> http://gcc.gnu.org/ml/gcc-patches/2003-04/msg02176.html
>
> Prior to this patch expand_unreachable_stmt used to return a bool,
> indicating whether control reached the end of the given statement
> list.  After, the return value was converted to a "tree" with the
> intention that the value NULL_TREE corresponds to false, and any
> non-NULL value was equivalent to true.
>  
Given the very clear explanation, this is fine for 3.4.  Thanks for the 
quick fix!

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Mark Mitchell
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