--- a/sci-visualization/paraview/paraview-5.6.0-r1.ebuild	
+++ a/sci-visualization/paraview/paraview-5.6.0-r1.ebuild	
@@ -107,6 +107,7 @@ pkg_setup() {
 	[[ ${MERGE_TYPE} != "binary" ]] && use openmp && tc-check-openmp
 	python-single-r1_pkg_setup
 	PVLIBDIR=$(get_libdir)/${PN}-${MAJOR_PV}
+	use coprocessing && CMAKE_MAKEFILE_GENERATOR="emake"
 }
 
 src_prepare() {