RE: [PATCH] KVM: selftests: add -MP to CFLAGS
From: David Laight
Date: Sun Oct 29 2023 - 17:13:37 EST
From: David Woodhouse
> Sent: 28 October 2023 20:35
>
> Using -MD without -MP causes build failures when a header file is deleted
> or moved. With -MP, the compiler will emit phony targets for the header
> files it lists as dependencies, and the Makefiles won't refuse to attempt
> to rebuild a C unit which no longer includes the deleted header.
Won't a phony target stop a header being built if there is
an actual rule to build it?
I usually add:
%.h:
echo "Ignoring stale dependency for $@"
Which only applies if there isn't an explicit rule.
David
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