- Linus Torvalds added hidden tabs to Kconfig to challenge parsers that can’t handle them.
- Tabs were intentionally added to the common Kconfig file for page sizes to expose faulty parsers.
- Torvalds believes parsers unable to handle tabs shouldn’t be parsing kernel Kconfig files, aiming to force fixes.
Invalid, not an ABI change. Besides, this does not break, it only reveals existing breakage.