DPC++ compilation error in the DPCT migrated code

[Onswar]

I am examining the DPCT migration using a simple "CUDA 10.2 Runtime" project template.

When compiling the migrated DPC++ codes, it occurs the following compilation error.

1>In file included from kernel.dp.cpp:3:
1>In file included from C:\Program Files (x86)\Intel\oneAPI\dpcpp-ct\2021.1-beta09\include\dpct/dpct.hpp:27:
1>C:\Program Files (x86)\Intel\oneAPI\dpcpp-ct\2021.1-beta09\include\dpct/device.hpp(218,16): : error : no member named 'max_element' in namespace 'std'
1> std::max_element(sub_group_sizes.begin(), sub_group_sizes.end());

I think that it is same the previous post.

https://community.intel.com/t5/Intel-oneAPI-Base-Toolkit/dpct-dpct-hpp-device-hpp-requires-c-17-feature/td-p/1211562/jump-to/first-unread-message 

I confirmed occurring the compilation error in my migrated code after change to the project property

[DPC++]->[Language]->[C++ Language Standard]

/std:c++14, /std:c++17, /std:c++20

 respectively.

error log is same above.

std::max_element is defined at <algorithm> header, but it is not included in <dpct/dpct.hpp>

I tried the following modification, so compilation was succeeded.

before

#include <CL/sycl.hpp>
#include <dpct/dpct.hpp>

after

#include <CL/sycl.hpp>
#include <algorithm> /* INSERTED */
#include <dpct/dpct.hpp>

kernel.dp.cpp

It may be need #include <algorithm> in device.hpp, I think.

• Windows10 pro / Visual Studio Community 2019 (Version 16.7.3)
• Intel Celeron (Skylake)
• GPU: Gen9
• 27.20.100.8681 DCH
• Intel® DPC++ Compatibility Tool – toolkit version: 2021.1-beta09, extension version 2021.1.0.16, Package ID: w_oneAPI_2021.1.662
• Intel® oneAPI DPC++ Compiler – toolkit version: 2021.1-beta09, extension version 2021.1.0.16, Package ID: w_oneAPI_2021.1.2115
• CUDA 10.2

Thanks,

On

[AbhishekD_Intel · Accepted solution]

Hi On,

Thanks for reaching out to us.

The link to the post that you have mentioned is related to the Linux environment and that error is due to c++11 and c++14 standards.

The error you are getting is related to Windows System, though by default the compiler uses c++17 it will show this error in some environments. We have already reported this error to the concerned team.

As of now for a workaround, you can add #include <algorithm> in device.hpp file, so that you can compile all of your migrated codes without getting such error.

Warm Regards,

Abhishek

[Onswar]

Thanks, response.

To use the suggested workaround is no problem, I can advance my experiments.

Regards,

On

[AbhishekD_Intel]

Hi On,

Thanks for the confirmation, please feel free to post a new thread if you have any other issues.

Warm Regards,

Abhishek