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Design notes: I1 requires the kernel-abi (mcpp-index#748) #930

Job	Run time
what the change starts	8s
documentation and repository checks	30s
build-windows	-1s
build-linux	-1s
build-macos	-1s
cross	-1s
upgrade	-1s
macos-ios	-1s
build-linux-arm	-1s
windows-msvc-xlings	-1s
linux-e2e	-1s
windows-e2e	-1s
windows	-1s
openkal	-1s
macos-e2e	-1s
linux	-1s
bootstrap	-1s
macos	-1s
target-matrix	-1s
the run's tests, reported	0s
every e2e test runs somewhere	0s
	21s