TYPO3 Core

True, but I don't feel that this is a bug as I don't see any reason for exporting empty directories.
Can you please be so kind to provide an example whre this is needed?

This IS required for every extension that uses the Smarty Extension/plugin as in that case you need a folder called templates_c where the cached templates get stored! (and that is empty on default)

o.k. I didn't know that. As far as I have looked into the code now this could be some bigger issue..

I just skimmed through the smarty docs and didn't see anything about the templates_c dir has to stay empty. So would it be a workaround for you to just setup an empty index.html file inside this folder?
If so I would like to change the severity to feature-request to let the core programers focus on bugs that has to be fixed before the next release.

ok - find someone who can do that then

It seems that there is (now?) a function to let the em generate empty folders by setting the the array in em_conf.php, 'createDirs=csv'
So what might be missing is a function to fill these value automaticaly.

[1] http://typo3.org/documentation/document-library/doc_core_api/ext_emconf_php/

I have just looked into the code of the Extension Manager.
It is really difficult to implement the feature that empty directories are included as well, because currently the EM consistently ONLY works with files, it doesn't deal with directories at all.
There is no inormation about the directories to be created in the t3x file, there are just the file paths. The dirs are then created kind of on-demand by means of the file paths.

So obviously they are only created if there's a file in it.

This "concept" is unfortunately spread all over the EM code so it would involve a rather big change to implement it.
Anyway there is, as Hans (case2020) outlined, the workaround to let the EM create empty folders with createDirs="somefolder".
I'm not sure if that is limited to subfolders of uploads/ though. If so, it would not serve as a workaraound.
On the other hand you can just create a dummy file in every empty folder and then the folder will be shipped with the t3x file as well.

This bug will not be fixed for 3.7, maybe later.

Setting resolution to "Won't fix". It's not worth the effort.