gmake-3.80 bug?

[Noel Yap]

I'm not sure if this has been reported by anyone, but the following makefile:
define _append
  ifeq ($(filter $(1),$(AOEU)),)
    AOEU += $(1)
  endif
endef

append = $(eval $(call _append,$(1)))

ifndef aoeu
aoeu := 1

$(call append,aoeu)

endif

.PHONY: aoeu
aoeu:
        @echo $(AOEU)


produces:
yapn:address@hidden:~/proj/aoeu> gmake aoeu
GNUmakefile:11: *** missing `endif'.  Stop.


but take out the ifndef:
define _append
  ifeq ($(filter $(1),$(AOEU)),)
    AOEU += $(1)
  endif
endef

append = $(eval $(call _append,$(1)))

aoeu := 1

$(call append,aoeu)

.PHONY: aoeu
aoeu:
        @echo $(AOEU)


and it works fine:
yapn:address@hidden:~/proj/aoeu> gmake aoeu
aoeu


Any ideas?

Thanks,
Noel
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