[Factor-builds] mason on macosx-x86-32: build loop error

[<sl...@fa...>]

Fatal error on shill.local

Unix system call failed:

Broken pipe (32)
(U) Quotation: [ set-namestack init-catchstack self quot>> call -> stop ]
(O) Word: build-loop
(O) Word: update-sources
(O) Word: latest-boot-image
(O) Word: maybe-download-image
(O) Word: need-new-image?
(O) Word: download-checksum
(O) Word: download-checksums
(O) Word: http-request
(O) Word: ( gensym )
(O) Word: <request-socket>
(O) Word: <client>
(O) Method: M\ array (client)
(O) Method: M\ object (client)
(O) Word: wait-to-connect
(O) Word: (io-error)
(O) Word: unix-error
(O) Method: M\ object throw
(U) Quotation: [
        63 special-object error-thread set-global
        continuation -> error-continuation set-global
        [ original-error set-global ] [ rethrow ] bi
    ]