PostGIS error building with `make` in ./extensions: nothing to be done for 'comments'

I'm using code I checked out from SVN. Whenever I run make in ./extensions/, I get make for DIR in postgis postgis_tiger_geocoder postgis_topology address_standardizer; do \ echo "---- Making all in ${DIR}"; \ make -C "${DIR}" all || exit 1; \ done ---- Making all in postgis make: Entering directory '/home/ecarroll/code/postgis/extensions/postgis' mkdir -p sql_bits/ /usr/bin/perl -pe 's/BEGIN\;//g ; s/COMMIT\;//g' ../../postgis/postgis_for_extension.sql > sql_bits/postgis.sql make -C ../../doc comments make: Entering directory '/home/ecarroll/code/postgis/doc' make: Nothing to be done for 'comments'. make: Leaving directory '/home/ecarroll/code/postgis/doc' cp ../../doc/postgis_comments.sql sql_bits/postgis_comments.sql cp: cannot stat '../../doc/postgis_comments.sql': No such file or directory Makefile:72: recipe for target 'sql_bits/postgis_comments.sql' failed make: *** [sql_bits/postgis_comments.sql] Error 1 make: Leaving directory '/home/ecarroll/code/postgis/extensions/postgis' Makefile:26: recipe for target 'all' failed Whenever I run make comments in the root I get a small portion of those errors, make comments make -C doc comments make: Entering directory '/home/ecarroll/code/postgis/doc' make: Nothing to be done for 'comments'. make: Leaving directory '/home/ecarroll/code/postgis/doc' How do I resolve this?