helm mode completion doesn't work correctly

[jtroo]

When I call ggtags-find-definition, it appears to open up in helm mode but doesn't work correctly. When I input a space, it just eliminates all of the match entries (goes to 0 candidates) instead of the expected behaviour which is to begin a new filtering match for helm.

Some additional details:
ggtags-completing-read-function is set to nil
buffer opens up with the name "helm-mode-ggtags-find-definition"
helm completion is working in other packages such as projectile and helm-gtags

[thermopyle]

I don't even get it to open a helm buffer, no matter what I set ggtags-completing-read-function to. ggtags-find-definition or ggtags-find-tag-dwim always open up the usual ggtags-global buffer and not a helm buffer. helm-mode is enabled globally.