Cython extension cimporting dpctl fails to compile in C

[oleksandr-pavlyk]

A simple Cython extension that involved cimport dpctl translated to C can not be compiled.

# File: a.pyx
# cython: language=c
# cython: language_level=3

cimport dpctl as c_dpctl
import dpctl

def foo(c_dpctl.SyclQueue q):
    return q.sycl_device.max_compute_unit

Then execute cythonize a.pyx to produce a.c. Compile the file using

gcc -fmax-errors=1 a.c -I$(python -c "import dpctl; print(dpctl.get_include())") -I$(python3-config --includes)

This results in a compilation error due to undefined type bool:

In file included from a.c:638:
/localdisk/repos/dpctl/dpctl/include/dpctl_sycl_device_interface.h:99:1: error: unknown type name ‘bool’
   99 | bool DPCTLDevice_IsAccelerator(__dpctl_keep const DPCTLSyclDeviceRef DRef);
      | ^~~~
compilation terminated due to -fmax-errors=1.

[oleksandr-pavlyk]

I suppose DPCTL-capi headers should define bool type when the compiler is not __cplusplus__.

[diptorupd]

@oleksandr-pavlyk can you try gcc -fmax-errors=1 a.c -I$(python -c "import dpctl; print(dpctl.get_include())") -I$(python3-config --includes) -std=c99. bool is in the C99 standard and we should not need anything extra unless we need older C standard support.

[oleksandr-pavlyk]

Using -std=c99 does not seem to help:

(idp) [11:19:39 ansatnuc04 issue_c_cython_dpctl]$ gcc -fmax-errors=1 a.c -I$(python -c "import dpctl; print(dpctl.get_include())") -I$(python3-config --includes) -std=c99
In file included from a.c:638:
/localdisk/work/opavlyk/repos/dpctl/dpctl/include/dpctl_sycl_device_interface.h:99:1: error: unknown type name ‘bool’
   99 | bool DPCTLDevice_IsAccelerator(__dpctl_keep const DPCTLSyclDeviceRef DRef);
      | ^~~~
compilation terminated due to -fmax-errors=1.

The compiler is not old:

(idp) [11:19:50 ansatnuc04 issue_c_cython_dpctl]$ gcc --version
gcc (Ubuntu 9.3.0-17ubuntu1~20.04) 9.3.0
Copyright (C) 2019 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

By the way, it would be cool if dpctl provided __main__.py to enable generation of includes with -I$(python -m dpctl --includes).

[oleksandr-pavlyk]

Evidently, one needs to #include <stdbool.h>.