fail loudly on unsized by-ref invariants (#1644) #4422

Job	Run time
test_llvm	3m 52s
rustfmt	13s
bench	5m 46s
todo_check	24s
dist (macos-15-intel, x86_64-apple-darwin)	2m 57s
dist (macos-latest, aarch64-apple-darwin)	1m 49s
dist (windows-latest, x86_64-pc-windows-gnu)	2m 52s
dist (windows-latest, x86_64-pc-windows-msvc)	2m 29s
dist (ubuntu-24.04-arm, aarch64-unknown-linux-gnu)	1m 51s
dist (ubuntu-22.04, x86_64-unknown-linux-gnu)	1m 43s
test (ubuntu-latest, s390x-unknown-linux-gnu, gcc-s390x-linux-gnu qemu-user)	4m 13s
test (macos-latest, aarch64-apple-darwin)	10m 27s
test (ubuntu-latest, x86_64-unknown-linux-gnu)	10m 10s
test (ubuntu-latest, riscv64gc-unknown-linux-gnu, gcc-riscv64-linux-gnu qemu-user)	4m 10s
test (windows-latest, x86_64-pc-windows-msvc)	16m 0s
test (macos-15-intel, x86_64-apple-darwin)	15m 48s
test (ubuntu-24.04-arm, aarch64-unknown-linux-gnu)	9m 12s
test (windows-latest, x86_64-pc-windows-gnu)	20m 33s
release	11s
	1h 54m 40s

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