Ignore error status codes occurred while compiling site-packages
directory.
diff --git a/Makefile.pre.in b/Makefile.pre.in
index 512185f..9a50039 100644
--- a/Makefile.pre.in
+++ b/Makefile.pre.in
@@ -718,11 +718,11 @@
 		./$(BUILDPYTHON) -Wi -tt -O $(DESTDIR)$(LIBDEST)/compileall.py \
 		-d $(LIBDEST) -f \
 		-x 'badsyntax|site-packages' $(DESTDIR)$(LIBDEST)
-	PYTHONPATH=$(DESTDIR)$(LIBDEST)  $(RUNSHARED) \
+	-PYTHONPATH=$(DESTDIR)$(LIBDEST)  $(RUNSHARED) \
 		./$(BUILDPYTHON) -Wi -t $(DESTDIR)$(LIBDEST)/compileall.py \
 		-d $(LIBDEST)/site-packages -f \
 		-x badsyntax $(DESTDIR)$(LIBDEST)/site-packages
-	PYTHONPATH=$(DESTDIR)$(LIBDEST) $(RUNSHARED) \
+	-PYTHONPATH=$(DESTDIR)$(LIBDEST) $(RUNSHARED) \
 		./$(BUILDPYTHON) -Wi -t -O $(DESTDIR)$(LIBDEST)/compileall.py \
 		-d $(LIBDEST)/site-packages -f \
 		-x badsyntax $(DESTDIR)$(LIBDEST)/site-packages