diff --git a/build_files/build_environment/cmake/ispc.cmake b/build_files/build_environment/cmake/ispc.cmake
index 160088bc16f..17429a3dd67 100644
--- a/build_files/build_environment/cmake/ispc.cmake
+++ b/build_files/build_environment/cmake/ispc.cmake
@@ -43,6 +43,7 @@ set(ISPC_EXTRA_ARGS
-DISPC_INCLUDE_TESTS=Off
-DCLANG_LIBRARY_DIR=${LIBDIR}/llvm/lib
-DCLANG_INCLUDE_DIRS=${LIBDIR}/llvm/include
+ -DPython3_EXECUTABLE=${PYTHON_BINARY}
${ISPC_EXTRA_ARGS_WIN}
${ISPC_EXTRA_ARGS_APPLE}
${ISPC_EXTRA_ARGS_UNIX}
@@ -61,6 +62,7 @@ ExternalProject_Add(external_ispc
add_dependencies(
external_ispc
ll
+ external_python
)
if(WIN32)
diff --git a/build_files/build_environment/cmake/openimagedenoise.cmake b/build_files/build_environment/cmake/openimagedenoise.cmake
index 3612e91a690..14a730d69b6 100644
--- a/build_files/build_environment/cmake/openimagedenoise.cmake
+++ b/build_files/build_environment/cmake/openimagedenoise.cmake
@@ -9,6 +9,7 @@ set(OIDN_EXTRA_ARGS
-DOIDN_STATIC_RUNTIME=OFF
-DISPC_EXECUTABLE=${LIBDIR}/ispc/bin/ispc
-DOIDN_FILTER_RTLIGHTMAP=OFF
+ -DPYTHON_EXECUTABLE=${PYTHON_BINARY}
)
if(WIN32)
@@ -38,6 +39,7 @@ add_dependencies(
external_openimagedenoise
external_tbb
external_ispc
+ external_python
)
if(WIN32)