[clangd-dev] omp.h not found by clangd

[Ilya Biryukov via clangd-dev]

Sorry for the late response.

Am So., 9. Dez. 2018, 17:04 hat Kadir Çetinkaya via clangd-dev <
clangd-dev at lists.llvm.org> geschrieben:

> As long as `/usr/lib/gcc/x86_64-pc-linux-gnu/8.2.1/include` is specified
> in your compile command, clangd should be able to find that file.
>
True, but gcc does not need that include path. So if you have
compile_commands.json generated for gcc, clangd (or any clang-based tool)
won't find omp.h

Asking the users to specify the -I to the gcc internal header is definitely
not a nice UX, for the same reasons we don't ask to specify a path to the
C++ STL and auto-detect it instead.
(It's a bit different with omp.h, since it's actually part of the gcc
internal headers and adding those to include dirs is not a good idea. I
assume that's the reason we don't have auto-detection in the first place.)

So it seems we have a few options:
- tell clangd to use the third-party, but not gcc-internal, OpenMP header.
- ship the LLVM's OpenMP alongside clang/clangd. (Maybe it's already
included in the llvm releases)
- figure out a way to make clang detect compatible GCC's omp.h header
without adding the whole internal gcc include dir to search paths.

The last option is certainly the most user-friendly one, but it's probably
too much work. I'd go with documenting this particular problem and
providing one or two ways to workaround it.



> On Thu, Dec 6, 2018 at 3:54 PM Daan De Meyer via clangd-dev <
> clangd-dev at lists.llvm.org> wrote:
>
>> Installing the openmp package on Arch Linux made clangd find the omp.h
>> header (/usr/include/omp.h). Is it possible to make clangd find gcc's omp.h
>> as well (located at /usr/lib/gcc/x86_64-pc-linux-gnu/8.2.1/include/omp.h on
>> my system)?
>>
>> Regards,
>>
>> Daan
>>
>> On Thu, 6 Dec 2018 at 15:32, Daan De Meyer <daan.j.demeyer at gmail.com>
>> wrote:
>>
>>> Hi,
>>>
>>> clangd doesn't seem to find omp.h which results in lots of diagnostics
>>> errors. I tried adding "include/omp.h", <omp.h> to the
>>> CanonicalIncludes.cpp file but that didn't seem to make a difference. Can
>>> someone give me some pointers on how to make clangd recognize omp.h?
>>>
>>> Regards,
>>>
>>> Daan
>>>
>> _______________________________________________
>> clangd-dev mailing list
>> clangd-dev at lists.llvm.org
>> http://lists.llvm.org/cgi-bin/mailman/listinfo/clangd-dev
>>
> _______________________________________________
> clangd-dev mailing list
> clangd-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/clangd-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/clangd-dev/attachments/20181228/bfb4d0e2/attachment.html>