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Re:On the Madness of Optimizing Compilers by randomsearch on Tuesday March 08, 2016 @03:07AM (#11244055)
Compiler bugs are not rare, quite the opposite, and this is often because of premature optimisation.

For example, GPGPU compilers are awful:

http://www.doc.ic.ac.uk/~afd/homepages/papers/pdfs/2015/PLDI...

Re:On the Madness of Optimizing Compilers by DannyBee on Tuesday March 08, 2016 @04:13AM (#11244255)
It's more that compiler vendors who compete mainly on the basis of worthless benchmarks do awful things.

This is one of the reasons gcc/llvm won: they don't care about that stuff. I mean, they care about performance, but not at all costs like these guys care.

At some point, people wanted compilers that did less stupid things. So they moved to the vendors who did that.

The reason it's so awful in the GPGPU space is because none of these vendors produce compilers yet. Instead, the vendors you have are those whose main goal in life is to generate better performance numbers than the other guy.

Ask anyone about the old days of fortran compilers and early optimizing C compilers and what have you.

What exists now is essentially "what happened after the market pushed back". Sadly, it didn't go as far as some people want (in either direction).

Re:On the Madness of Optimizing Compilers by loup-vaillant on Tuesday March 08, 2016 @07:04AM (#11244762)
> This is one of the reasons gcc/llvm won: they don't care about that stuff. I mean, they care about performance, but not at all costs like these guys care.

Really? http://www.complang.tuwien.ac.at/kps2015/proceedings/KPS_201... https://news.ycombinator.com/item?id=11219874

While GCC and LLVM do care about implementing the standard correctly, they show little mercy to the poor developer who failed to avoid one of the many sharp corners of undefined behaviour.

Re:On the Madness of Optimizing Compilers by DannyBee on Wednesday March 09, 2016 @12:31PM (#11254289)
Yes. Really.

There was a long thread about this just a few days ago (https://news.ycombinator.com/item?id=11219874)

I already commented there, and since i didn't always have pleasant things to say, i'm not going to repeat them here.