If you run solr_create_index and specify a bulk_count of 0

php -d memory_limit=-1 app/console ezplatform:solr_create_index --env prod 0

or if you specify a string

php -d memory_limit=-1 app/console ezplatform:solr_create_index --env prod demo

If still creates the search index, but the command will not exit, it will be stuck in a loop.
The cause is that bulk_count accepts a value <= 0. It should only consider integer values higher than zero.