[llvm-dev] Optimizer issues on Windows

[David Majnemer via llvm-dev]

$ ~/llvm/Debug+Asserts/bin/llc try.ll
$ echo $?
0

On Sat, Sep 12, 2015 at 6:39 AM, Sebastian Blessing via llvm-dev <
llvm-dev at lists.llvm.org> wrote:

> This got me into thinking. Indeed the problem is related to Windows
> exceptions, so I am not sure whether the bug reported
> <https://llvm.org/bugs/show_bug.cgi?id=24374> is actually fixed.
>
> Compiling Pony code (helloworld) that includes no exceptions does work
> fine (with optimizations). As soon as exceptions on windows come into play,
> writing the object file dies with the mentioned error in MCStreamer.cpp.
>
> Here <http://releases.ponylang.org/winexcept/> are two minimal IR
> examples (helloworld.ll works, try.ll doesn’t - both verify with llc). The
> relevant method is *@Main_create*. Can anyone of you guys confirm the
> issue with llvm 3.7.0–final, or whether said bug has actually been fixed?
>
> From: Reid Kleckner
> Date: Friday 11 September 2015 17:07
> To: Sebastian Blessing
> Cc: "llvm-dev at lists.llvm.org"
> Subject: Re: [llvm-dev] Optimizer issues on Windows
>
> The bug https://llvm.org/bugs/show_bug.cgi?id=24374 has to do with
> exceptions on Windows, so it is unrelated unless you are using them.
>
> On Fri, Sep 11, 2015 at 4:37 AM, Sebastian Blessing via llvm-dev <
> llvm-dev at lists.llvm.org> wrote:
>
>> Dear Community,
>>
>> The ponyc <https://github.com/CausalityLtd/ponyc/tree/llvm37> (llvm37
>> branch) project is facing an issue on Windows:
>>
>> When optimizations are turned on (llvm 3.7.0-final and more specifically
>> <https://github.com/CausalityLtd/ponyc/blob/llvm37/src/libponyc/codegen/genopt.cc>,
>> opt-level 3,  BBVectorize, LoopVectorize, SLPVectorize, RerollLoops,
>> LoadCombine + a custom heap to stack pass) writing an object file aborts
>> (on Windows only) with the following fatal error:
>>
>> “Starting a function before ending the previous one!” at
>> MCStreamer.cpp:407 during LLVMTargetMachineEmitToFile. Verifying the IR
>> with llc raises no errors.
>>
>> What exact problem is being detected here and how can we get more details
>> on the location in the IR that is causing the problem?
>>
>> Turning off optimizations successfully writes the object file. This only
>> occurs on Windows, writing object files works fine on Linux and OS X.
>>
>> Is this a know issue with LLVM 3.7.0-final and how can this be fixed? Is
>> a patch required?
>>
>> This might be related to https://llvm.org/bugs/show_bug.cgi?id=24374.
>>
>> Kind regards
>> Sebastian
>>
>>
>>
>> _______________________________________________
>> 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
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/llvm-dev/attachments/20150912/7bf7fbce/attachment.html>