When !GRANT_TABLE and !PV_SHIM headers-n contains grant_table.h twice, causing make to complain "target '...' given more than once in the same rule" for the rule generating the stub headers. We don't need duplicate entries in headers-n anywhere, so zap them (by using $(sort ...)) right where the final value of the variable is constructed.
Fixes: 6bec713f871f ("include/compat: produce stubs for headers not otherwise generated") Signed-off-by: Jan Beulich <jbeul...@suse.com> --- a/xen/include/Makefile +++ b/xen/include/Makefile @@ -34,7 +34,7 @@ headers-$(CONFIG_TRACEBUFFER) += compat/ headers-$(CONFIG_XENOPROF) += compat/xenoprof.h headers-$(CONFIG_XSM_FLASK) += compat/xsm/flask_op.h -headers-n := $(filter-out $(headers-y),$(headers-n) $(headers-)) +headers-n := $(sort $(filter-out $(headers-y),$(headers-n) $(headers-))) cppflags-y := -include public/xen-compat.h -DXEN_GENERATING_COMPAT_HEADERS cppflags-$(CONFIG_X86) += -m32