Re: [Tinycc-devel] [bootstrappable] Re: Re: wip-full-source-bootstrap: from a 357-byte `hex0' to 'hello'

[Vincent Lefevre]

On 2021-01-08 13:36:26 +0000, Orians, Jeremiah (DTMB) wrote:
> > If so, is libc malloc supposed to ensure alignment of allocated memory?
> > According to https://man7.org/linux/man-pages/man3/malloc.3.html yes.
> > @Janneke: So our mes libc malloc should be aligning the stuff--but it's not 
> > doing it.  So it's a bug in our libc.
> 
> Looks like you'll have to waste 3.7bytes on average per malloc to
> always pad to the 8byte boundary.

Note that it's an 8-byte boundary for 32-bit systems, but a 16-byte
boundary for 64-bit systems:

  https://www.gnu.org/software/libc/manual/html_node/Aligned-Memory-Blocks.html

And about the average waste, this depends on other factors (the
main one may be that the block size is often a multiple of some
power of two).

-- 
Vincent Lefèvre <vincent@vinc17.net> - Web: <https://www.vinc17.net/>
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