RE: [PATCH 0/4] -ffreestanding/-fno-builtin-* patches

From: David Laight
Date: Wed Aug 19 2020 - 04:27:02 EST


From: Arvind Sankar
> Sent: 18 August 2020 23:26
...
> gcc-10 optimizes the generic memset implementation in there into a call
> to memset. Now that's on x86 which doesn't use the generic
> implementation, but this is just waiting to bite us.
>
> https://godbolt.org/z/6EhG15

Gah, if I want a call to memset() I'll write a call to memset().
If I'm trying to zero a small number of bytes I'll write a loop
because it'll be faster.

I wish compilers wouldn't even consider these sorts of 'optimisations'.

David

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