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<span style="font-family: monospace;">I've wondered for a good while
if using O2 on stage1 might be worth it.<br>
<br>
So I did some measurements and it should be worth it for most cases.<br>
<br>
For a single "quick" flavour build they are more or less on equal
footing.<br>
If you rebuild stage2 multiple times reusing stage1 it will be faster.<br>
If you build stage2 with optimizations/profiling it will be faster.<br>
<br>
Below are the timings using "time make -j9" for a quick build.<br>
I forgot to write down the seconds as I didn't expect them to be so
close.<br>
But it is what it is.<br>
<br>
Timings stage1 options O1 vs O2, quick build after make clean:<br>
<br>
stage1 opt | time (wall) | time (user)<br>
-O1 | 13m | 53m<br>
-O2 | 13m | 51m<br>
<br>
I've also run the numbers for a optimized stage2 compiler a while ago,<br>
where stage1 with O2 was faster.<br>
But I no longer have these numbers around.<br>
<br>
So it seems safe to say one should use O2 if either:<br>
* stage2 is built with optimizations<br>
* you freeze stage1 and reuse it while working on stage2<br>
<br>
<br>
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