It seems the uppercase form is more popular so far:

# git grep -l '_USE=.*xorg=' -- '*/*/Makefile' | wc -l
      55
# git grep -l '_USE=.*XORG=' -- '*/*/Makefile' | wc -l
     182
# git grep -l '_USE=.*qt=' -- '*/*/Makefile' | wc -l
      28
# git grep -l '_USE=.*QT=' -- '*/*/Makefile' | wc -l
     111
# git grep -l '_USE=.*kde=' -- '*/*/Makefile' | wc -l
       5
# git grep -l '_USE=.*KDE=' -- '*/*/Makefile' | wc -l
      18
# git grep -l '_USE=.*gnome=' -- '*/*/Makefile' | wc -l
      66
# git grep -l '_USE=.*GNOME=' -- '*/*/Makefile' | wc -l
     229

So, we could discuss updating the porter's handbook instead. But I personally think lowercase comes more natural for the *content* of a variable, and the conversion to uppercase when applying it is there for a reason.

In D37861#860185, @zirias wrote:

It seems the uppercase form is more popular so far:

# git grep -l '_USE=.*xorg=' -- '*/*/Makefile' | wc -l
      55
# git grep -l '_USE=.*XORG=' -- '*/*/Makefile' | wc -l
     182
# git grep -l '_USE=.*qt=' -- '*/*/Makefile' | wc -l
      28
# git grep -l '_USE=.*QT=' -- '*/*/Makefile' | wc -l
     111
# git grep -l '_USE=.*kde=' -- '*/*/Makefile' | wc -l
       5
# git grep -l '_USE=.*KDE=' -- '*/*/Makefile' | wc -l
      18
# git grep -l '_USE=.*gnome=' -- '*/*/Makefile' | wc -l
      66
# git grep -l '_USE=.*GNOME=' -- '*/*/Makefile' | wc -l
     229

So, we could discuss updating the porter's handbook instead. But I personally think lowercase comes more natural for the *content* of a variable, and the conversion to uppercase when applying it is there for a reason.

Majority=uppercase, maybe that should be the documented way?

I personally fail to see any benefit from the lower-case notation.

No other opionions?

Well, my interpretation was that UPPERCASE is reserved to variable *names*. Of course that's debatable here, as these variables just "aggregate" other variables ...

Someone added the case conversion when expanding them, so obviously had something in mind ;-) But of course we could also just drop that (simplifying the code) and update the porters' handbook instead.