overwriting NOT_FOR_ARCHS via /etc/make.conf has no effect

[Anton Shterenlikht]

I'm trying to overwrite a Makefile variable via /etc/make.conf
It doesn't seem to work:

# cd /usr/ports/lang/gcc43
# grep NOT Makefile
NOT_FOR_ARCHS=  alpha ia64
# grep -C1 NOT /etc/make.conf
.if ${.CURDIR:M*/lang/gcc4*}
NOT_FOR_ARCHS= ia64
.endif
# make
===>  gcc-4.3.3_20090122 does not run on alpha ia64, while you are running alpha.
*** Error code 1

Stop in /usr/ports/lang/gcc43.
# 

What am I doing wrong?

many thanks
anton

-- 
Anton Shterenlikht
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Mech Eng Dept
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