poudriere options -c does not work as expected?

[Anton Shterenlikht]

I need to change options for several ports to get
them build on ia64, e.g. 
===>  Configuring for R-3.0.1
libquadmath is not available for your compiler and architecture: please enable the MISSING option.
*** Error code 1
make: stopped in /usr/ports/math/R

I set the options with "poudriere options -c math/R".

But the option doesn't seem to be set:

# make -C  /pdr/ports/math/R showconfig |grep MISSING
     MISSING=off: use libmissing rather than libquadmath
#

So when I redo poudriere bulk again, the same failure
happens.

Anton