qmake CONFIG+=Debug leads to release builds

There's something counter-intuitive in the way QMake treats CONFIG parameters for controlling "debug" vs. "release" builds. Passing CONFIG+=Debug will in fact lead to a release build, since QMake seem to perform a case-sensitive comparison to "debug" internally.

This is problematic, since both CMake and Visual Studio uses "Debug" & "Release" for build configuration. Using the same build configuration strings across CMake & QMake projects is therefore susceptible to accidental mis-compiles.

Example of accidental release build on Windows due to passing "Debug" instead of "debug":

qmake CONFIG+=Debug
nmake
:: A release build is generated despite asking for a "Debug" build

The same problem also seem to occur on MacOS.

Request: Could it be possible to either:

• Make the QMake CONFIG parameter case-insensitive, so that "Debug" and "Release" will work as expected; or
• Extend the QMake https://doc.qt.io/qt-6/qmake-variable-reference.html#config documentation to explicitly state that "debug" and "release" are case-sensitive, and that "Debug" will not lead to a debug build.