mutliple PROGNAME not working correctly about nuttx-apps

[normanr]

Instead of finding the index of the string, you could zip the two lists together (https://riptutorial.com/makefile/example/23643/zipping-lists), and then eval a template (https://www.gnu.org/software/make/manual/html_node/Eval-Function.html) for each pair.

[protobits]

This is the problematic line:
https://github.com/apache/incubator-nuttx-apps/blob/f3828ccbca3e45319d804cd5c3f91a4764de68c8/Application.mk#L185

[acassis]

Good finding @v01d ! Is this multiple buitin applications feature documented in some place?

[protobits]

Not really, it would be good to have a section in the docs explaining how to write an app (maybe under "applications").

[protobits]

A workaround is to not use main to define the entry point, the <progname>_main and thus not rely on this feature.

[acassis]

Well, in the past it was appxyz_main(), move to main() was an improvement. Maybe we can fix it without returning to the previous way to do it.

[protobits]

I don't really have a better proposal and don't really like the added complexity of the solution, so I will just leave this issue open in case someone thinks of a better approach. I mentioned the workaround in case someone bumps into the problem. I wasn't proposing we adopt it for existing apps, since it would be going backwards as you mention.

[xiaoxiang781216]

Yes, this is the right approach to fix this problem I discussed internally with @anchao .

[xuxin930]

Yes, this is the right approach to fix this problem I discussed internally with @anchao .

@anchao has fixed this incremental compilation issue in this excellent work #1603,
but there is also a potential risk:

Important

If an application has MAINSRCS with the same name in different directories,
function GETENTRYINDEX will have wrong results because notdir is used.

I plan to establish a mapping relationship between progname and src during defining variables.