[ptxdist] Speed up targetinstall of certain packages

["Gieseler, Christian" <CG@eks-engel.de>]

Hello,

I have question regarding the speedup of daily work.

We have frontend and backend of our webgui deployed with separate packages. Only task of these package is to deploy the files with 

@$(call install_tree, web-frontend, -, -, $(WEB_FRONTEND_DIR)/var-www/, /var/www/,no)

Compile and install stages are empty. The just call targetinfo and touch to skip the stages.

The frontend depends on the backend and the backend obviously depends on our application which is called by the backend. 
So our web-frontend.in file looks like this:
## SECTION=project_specific

config WEB_FRONTEND
	bool
	select APP_LAYER
	select WEB_BACKEND
	prompt "e-mode Web Frontend"
	help

As expected if i clean and compile APP_LAYER the targetinstallstage of Backend and Frontend are executed again. However this is only a Run-Time only dependency. It is a third-party archive and install_tree takes quite some time even on fast build hosts. Even it if is just a minute it is annoying to spend the time waiting during image creation. Trying to solve that i found "if RUNTIME"  für Run-Time only Dependencys in the documentation here:

https://www.ptxdist.org/doc/daily_work_section.html#controlling-package-dependencies-in-more-detail

So my expectation would be that if i change the webfrontend.in file like this:

config WEB_FRONTEND
	bool
	select APP_LAYER	if RUNTIME
	select WEB_BACKEND   if RUNTIME
	prompt "e-mode Web Frontend"
	help

The "if RUNTIME" would make sure that the targetinstall stage is not executed again if i just execute a "ptxdist clean app-layer" followed by a "ptxdist images". Same with ptxdist clean root; ptxdist images. It is clear that all targetinstall stages are executed again, but i would expect that the web-frontend is deployed earlier if no build dependency is given.

Am i missing something, oder is the "if RUNTIME" Switch not working properly in my ptxdist-2018.12 version? Or does it have no effect on targetinstall stages?

Thanks for any feedback.
BR,
Christian