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Re: Long term code compactness regression

> I compiled the Linux software package busybox with three different
> compiler versions on i386.
> compiler        opt     size
> gcc     -O2     213116
> gcc 2.95.4-pre  -Os     216652
> gcc 3.0.2-pre   -Os     222012
> Binaries were stripped, and the .note and .comment sections were
> removed.
> This is indicating that gcc does *better* with -O2 than 2.95
> and 3.x with -Os. If I broke these down to specific testcases and
> compared the assembly output, would anyone look at fixing the behavior
> of -Os?
Some of work has been already done at 3.1.x branch. See Andreas tester for development of size of binaries on mainline
that is mostly decreasing.

For i386, you may try -mpreferred-stack-boundary=2 that is the most common
cause of code size growth on 2.95.0+ compilers for i386.

In case you notice some simple enought testcases to fix, I would happily
look at it, as code size is definitly important parameter, but it would be
nice if you did it for mainline, as 3.0.x branch is not here to fix such
a problems.


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