Conversation

Not only is the recipient of your code possibly using a different compiler version with different warnings, in which case you'll just break their build and annoy them...
1
24
If you break the build for them by shipping with -Werror, the likely outcome is that they start making random changes to the code the compiler warns about until the warning goes away, possibly BREAKING THE CODE IN DANGEROUS WAYS.
1
30
Summary: -Werror is only meaningful with a known compiler version and build target, and only to developers who can meaningfully act on the failures. Don't ship with -Werror. Ever.
2
44
Replying to
Since the Linux kernel doesn't follow the C memory model and disregards undefined behavior rules they don't agree with, it's fairly dangerous to use a newer compiler than what they're broadly using and testing themselves. Ideally, they'd actually list what's being tested / used.
2
Replying to and
It's pretty common for there to be regressions via subtle bugs introduced due to compiler bugs or kernel bugs triggered only on certain toolchains, generally the newer ones that aren't widely used / tested yet. Of course you also get a lot of bug fixes through those new versions.
1