Eric S. Raymond Calls LLVM The "Superior Compiler" To GCC

[wizard69]

This "discussion", between ESR and RMS could turn out quite funny, time to grab the popcorn.

Especially when RMS doesn't have a leg to stand on. His arguments seem to come from emotion not rational thinking.

[wizard69]

It is fast because it does less optimizations, produces slower code. And yes, in the long run Linux kernel will be less free if it switches to clang.

This isn't the case at all! The more compilers that can successfully build the kernel the freer the kernel is. Being restricted to one compilers is the opposite of free.

For example it could require proprietary extensions to compile and use GPGPU features and that could pretty much become a stnadard in HPC, which would in turn make Linux proprietary if you want to use it in HPC.

This could that could is just a way of saying you have no rational argument. A kernel that can be compiled by a wide array of compilers is less proprietary than what we have today. Besides in many HPC installations the kernel is a minor element in a very large and already proprietary code base.

[wizard69]

It doesn't have to be developer decision, lets say HPC community wants to use HSA enabled processors, with proprietary HSA back-ends. No change in code of Linux, but proprietary compiler based on LLVM would make it run faster.

I beleive that LLVM/Clang stuff is devils business, not gona touch with a ten foot pole.

I can't even parse what you are trying to say here. You do realize that much of the code run by the HPC community is already proprietary.

[Calinou]

Everyone is free to choose what hardware they want to use. If this would be the case then you have a valid point to not use said hardware. Problemo? After all if we talk about freedom we should not talk about our freedom only. We should talk about everyone's freedom. So people should be able to make their proprietary stuff no matter how evil it might seem.

Freedom and anarchy are very different concepts. You seem to be going for the latter.

[yoshi314]

firefox does compile with clang for quite some time (by extension so does spidermonkey), so does mesa and libreoffice.
Not sure about the rest, I mostly use clang to compile these big pieces of software that would take minutes or hours on my box (firefox can take hours to compile and libreoffice takes forever as well).

For quite some time clang is the main compiler for my projects, but "release" stuff still uses gcc (mainly because it's faster and has nifty hardening features that clang doesn't posses just yet).

nice to know. i think i had some linking problems earlier with clang. could be the systemd container i used, as it acts funny with parallel make jobs sometimes (so far confirmed on two separate systems)

[blackiwid]

such a Nutjob just lost last few % respekt of that person, he said sometime ago something like "when I talk about opensource I mean the same that rms when he talkes about free software" now we now he did lie.

who the hell cares about what he thinks that is superior, if tomorow clang would vanish I would not care too. so this is no argument at all.

And even technicaly he either prooved that he has no plan at all or he lies again: "LLVM is superiour, by every metric I know", gcc produces faster/more optimised binaries.

What in reality does matter more than having faster compile times, you make something really wrong if you compile your software more often then people run it. so having good running experience is more important than having smaller compile times.

If as developer you care more about "compile+run" times and faster development vs faster programm-speed, you maybe should switch to a scripting language anyway.


BTW, emacs has a package manager wth does you need to include such stuff into the main package to keep emacs relevant? makes no sense at all...

M-x package-install clang-stuff RET

[ravyne]

Freedom and anarchy are very different concepts. You seem to be going for the latter.

In what way is extending the freedom you enjoy to make one choice to another person to make a different choice, anarchy?

The very essence of freedom is predicated on choice. To have the ability to choose differently and even actively disagree with the status quo is how you measure what freedom you have. But 'Freedom' on its own is merely a principle, a design pattern, if you will. It has to be placed in a context before it takes on concrete meaning; "the freedom to ...", "Freedom from ...", "Freedom of ..."

RMS doesn't really want freedom in principle, he wants freedom from proprietary software. He would prefers work in which no proprietary software exists, which by definition limits the individual choice of users. This doesn't make you less dependant on its own, it makes you dependant upon a different kind of entity -- GPL3 was a good example of what unintended consequences look like under the GNU entity.

Now, RMS and his views are far from unprincipled, but too many people equate GNU/GPL freedom from proprietary software with a more democratic ideal of freedom, when it is not that. It might even be closer to that, on the average, than a proprietary world would be, but still they are not the same ends. At the end of the day, RMS thinks he knows better than you what's good for you, and would prefer you to use GPL3 software over any other proprietary or competing open-source licensed software -- he doesn't really want you to have the full benefit of choice. He believes, as any benevolent dictator does, that a self-sustaining utopia will spontaneously spring up around his platform, and that it will serve all needs. I admire the man for much of what he's accomplished, but this is where he is disconnected from reality, IMO.

[SystemCrasher]

What is SDK/BSP?

Short answer: if you do not know it, you do not need it

Longer answer is: when you've got some new chunk of hardware and about to get your system (e.g. Linux) booting on that hardware, you may want some help. Vendors can elect to supply some ready solutions which would help devs to bring up new board. This usually implies compiler to build binaries for their arch, possibly some Linux version as reference, etc.

Formally SDK stands for Software Development Kit and BSP stands for Board Support Package.

Compiling the Linux kernel with LLVM doesn't make it any less free.

However, getting closed-source blob-only compiler built for only one of few chosen system, witout chances to get source of that compiler to rebuild it for system of my choice can be really unpleasant thing to face with. That's where BSD license suxx a lot.

LLVM is really fast too, so it could be useful for developers who want to re-compile it often.

I have powerful 8-cores CPU which builds whole full desktop Linux kernel in matter of 10 minutes with stock Ubuntu kernel config (zounds and zounds of kernel modules). And can also set up distributed build farm if I need even more speed. On other hand I care about code quality. That's where LLVM still got a lot to be desired and for example it STILL does not supports OpenMP, even it has been promised for about 2 years. Obviously it gives sucking performace in OpenMP programs if CPU got more than 1 core.

Also for people like Michael who use the Phoronix Test suite to do regression testing by bisecting. Then it compiles different kernel versions until it finds the regression.

From my experience, there're quite few things change when you bisect and only changed things have to be rebuild. Linking goes at light speed as long as you have enough RAM to enjoy 100% cache hits. So for myself, most time consuming thing at bisect is usually actually checking if particular version bugged or not if bug happens to have some intermittent nature or require long time to trigger (and most unfortunate bugs which can't be quickly nailed down are exactly like this).

[SystemCrasher]

People like choice, they can choose proprietary if it works better for them or they can choose open source if that is what they consider better.

I like choice too and I think it is really unfair that all these silly laws are prohibiting slavery. Wouldn't it be better for me if I can enslave you and make you sorry for your words, teaching you "by example"? And of course my ability to get some slaves would enhance my freedoms.

There is one little catch though: it screws up someone's else freedom. That's what proprietary pests fail to understand all the time. Then they're surprised to learn we want their slow and painful death and there're some good reasons we want it this way

[duby229]

I like choice too and I think it is really unfair that all these silly laws are prohibiting slavery. Wouldn't it be better for me if I can enslave you and make you sorry for your words, teaching you "by example"? And of course my ability to get some slaves would enhance my freedoms.

There is one little catch though: it screws up someone's else freedom. That's what proprietary pests fail to understand all the time. Then they're surprised to learn we want their slow and painful death and there're some good reasons we want it this way

I agree with you completely.

An analogy would be smokers. Yeah, sure you are free to smoke, but I'm free to breath clean air. There has to be a compromise. True freedom is somewhere in the middle.