--- xen-4.13.1/tools/ocaml/common.make~	2020-05-14 14:19:32.000000000 +0200
+++ xen-4.13.1/tools/ocaml/common.make	2021-03-26 11:08:01.558827358 +0100
@@ -9,7 +9,7 @@
 OCAMLYACC ?= ocamlyacc
 OCAMLFIND ?= ocamlfind
 
-CFLAGS += -fPIC -Werror -I$(shell ocamlc -where)
+CFLAGS += -fPIC -I$(shell ocamlc -where)
 
 OCAMLOPTFLAG_G := $(shell $(OCAMLOPT) -h 2>&1 | sed -n 's/^  *\(-g\) .*/\1/p')
 OCAMLOPTFLAGS = $(OCAMLOPTFLAG_G) -ccopt "$(LDFLAGS)" -dtypes $(OCAMLINCLUDE) -cc $(CC) -w F -warn-error F