[PATCH] newlib: Improve memory allocation for floating-point string

[Corinna Vinschen]

Hi Markus,

On Dec  5 15:20, Markus Eisenmann wrote:
> Hi!
> 
> IMHO, the commit "newlib: Fix memory leak regarding gdtoa-based _ldtoa_r()" [02/08/2023] has solved
> a memory leak issue, but I think there's still scenarios that may lead to memory corruption or exception.
> E.g., calling freedtoa() after gdto() frees the memory-block but does not invalidate the copy in the mp-result
> member in the reent-structure. Call _dtoa_r() or _ldtoa_r() afterwards will "free" this block twice and will
> corrupt the chain of free blocks.

Do you have a simple reproducer?

> In addition, I think that the previous implementation in gdto() - like used
> in phyton - that the value _Bigint::_k is stored in front of the memory instead in within the _reent-structure
> is more robust and is more flexible.

Why?  Again, do you have a reproducer to show that this has an advantage
or is more robust?


Thanks,
Corinna