/usr/pkgsrc/www/firefox52/work/firefox-52.9.0esr/db/sqlite3/src/sqlite3.c:
More details about your env needed - I have firefox52-52.9.0nb43 locally build on macppc -current from early June and the only changes to the Makefile were recursive revbumps that should not affect that part of the build.
NetBSD-9.99.98, amd64, tried after recent pkg_rolling-replace (meaning all other packages are up to date).
I just noticed now that firefox52-52.9.0nb46 finished fine on NetBSD-9.99.96 on Alpha, though. Hmmm...
John