[llvm-dev] For the LLVM wishlist

[ardi via llvm-dev]

Thanks a lot, Chris. However, during these weeks trying to build LLVM
myself, I learnt the issue is more of a mindset thing. I believed LLVM
was developed with a mindset/style similar to mine because its
warnings messages so closely match my way of coding, but, while
patching LLVM for building it in older systems, I learnt -from
patches/reports discussions- that LLVM development recommends
cutting-edge OS versions and discourages continued support of systems
that were supported at some moment.

That's a valid strategy, but opposite to my needs and my style. I
won't argue against it because it's a valid paradigm, but however it
turns clang into a compiler I'll only be able to use on a very small
subset of the Unices I support. I tried hard these weeks because I
really like clang, but I just found myself in a no way out road, a
symptom that it's not for me.

Thanks anyway,

ardi



On Sun, Apr 17, 2016 at 12:00 PM, Chris Bieneman via llvm-dev
<llvm-dev at lists.llvm.org> wrote:
> Ardi,
>
> Your comments about the compiler-rt build system being a problem are very correct. We're working on it. We're moving in a direction with the compiler-rt build system to separate the build logic for the sanitizers from the build logic for the builtins, and to clean up the interface between the top-level LLVM & Clang build systems and the compiler-rt one.
>
> -Chris
>
>>> On Apr 16, 2016, at 1:26 AM, Joerg Sonnenberger via llvm-dev <llvm-dev at lists.llvm.org> wrote:
>>>
>>>> On Fri, Apr 15, 2016 at 05:22:12PM +0200, ardi via llvm-dev wrote:
>>>>> On 4/15/16, Joerg Sonnenberger via llvm-dev <llvm-dev at lists.llvm.org> wrote:
>>>>> On Fri, Apr 15, 2016 at 02:31:59PM +0200, ardi via llvm-dev wrote:
>>>>> On Fri, Apr 15, 2016 at 1:02 PM, Joerg Sonnenberger via llvm-dev
>>>>> <llvm-dev at lists.llvm.org> wrote:
>>>>>>> On Fri, Apr 15, 2016 at 10:45:03AM +0200, ardi via llvm-dev wrote:
>>>>>>> What I found is that the build system is really complex, performs many
>>>>>>> checks, and quite often takes wrong decisions (example: a fatal error
>>>>>>> if the OS X version is older than 10.7, instead of just disabling
>>>>>>> sanitizers and continuing with the build --moreover, if you manually
>>>>>>> disable the sanitizers build, its tests are not disabled at make
>>>>>>> check-all, so you end up with many tests failing because of a
>>>>>>> component you didn't build).
>>>>>>
>>>>>> Huh? If you check out only llvm and clang, nothing is checked for the
>>>>>> sanitizers, they don't get built and they don't get tested.
>>>>>
>>>>> But if you don't check out compiler-rt, you don't get builtins.
>>>>> Missing the feature of getting highly optimized code output is a big
>>>>> miss, IMHO. And I don't think builtins require anything apart from a
>>>>> standard compiler.
>>>>
>>>> On most platforms you don't need compiler-rt except for the sanitizers.
>>>
>>> Wait, do you mean that builtins for processors like x86_64 or PowerPC
>>> aren't being used by clang? I understood builtins were a key lib for
>>> getting maximum performance on the processors it supports, but maybe I
>>> misunderstood it.
>>
>> Few builtins are lowered to libcalls on x86_64 and powerpc and those are
>> normally provided e.g. by libgcc already.
>>
>> Joerg
>> _______________________________________________
>> LLVM Developers mailing list
>> llvm-dev at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev