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Re: NDEBUG when building packages?

Ian Jackson <ijackson@chiark.greenend.org.uk> writes:
> Mathieu Malaterre writes ("Re: NDEBUG when building packages?"):

>> In that case, this should really be clarified. A lot of debian/cmake
>> packages are actually doing:


>> within there debian/rules files. This settings by default compiles
>> with: `-O3 -DNDEBUG`


> Certainly -DNDEBUG should never be used unless upstream explicitly say
> that it's intended to be supported, and usually not even then.

Also, -O3 is generally considered rather iffy.  It's not very well-tested
and in various versions of GCC it tended to make the code slower, not
faster (usually because it unrolled loops too far and blew the CPU cache).
It's also had various code generation bugs from time to time.

I wouldn't use -O3 without benchmarking of that specific code to confirm
that it really improves matters.

Russ Allbery (rra@debian.org)               <http://www.eyrie.org/~eagle/>

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