CXX, dpcpp used on Windows too

A work-around added to bld.bat to be removed in 2021.4

Author: oleksandr-pavlyk

conda-recipe/bld.bat

@@ -1,11 +1,9 @@
-call "%ONEAPI_ROOT%\compiler\latest\env\vars.bat"
-if errorlevel 1 (
-    echo "oneAPI compiler activation failed"
-    exit /b 1
-)
+
+REM A workaround for activate-dpcpp.bat issue to be addressed in 2021.4
+set "LIB=%CONDA_PREFIX%\Library\lib;%CONDA_PREFIX%\compiler\lib;%LIB%"
 
 "%PYTHON%" setup.py clean --all
-"%PYTHON%" setup.py install
+"%PYTHON%" setup.py install --sycl-compiler-prefix=%CONDA_PREFIX%\Library
 if errorlevel 1 exit 1
 
 rem Build wheel package

conda-recipe/meta.yaml

@@ -14,7 +14,7 @@ build:
 requirements:
     build:
         - {{ compiler('cxx') }}
-        - {{ compiler('dpcpp') }}  # [linux]
+        - {{ compiler('dpcpp') }}  # [not osx]
     host:
         - setuptools
         - cython