fail loudly on unsized by-ref invariants (rust-lang/rustc_codegen_cra… #4426

Job	Run time
todo_check	22s
test_llvm	4m 11s
rustfmt	11s
dist (windows-latest, x86_64-pc-windows-msvc)	4m 28s
bench	6m 31s
dist (windows-latest, x86_64-pc-windows-gnu)	5m 1s
dist (macos-latest, aarch64-apple-darwin)	2m 44s
dist (ubuntu-22.04, x86_64-unknown-linux-gnu)	3m 3s
dist (ubuntu-24.04-arm, aarch64-unknown-linux-gnu)	2m 37s
dist (macos-15-intel, x86_64-apple-darwin)	6m 40s
test (ubuntu-latest, s390x-unknown-linux-gnu, gcc-s390x-linux-gnu qemu-user)	5m 27s
test (ubuntu-latest, x86_64-unknown-linux-gnu)	12m 19s
test (macos-15-intel, x86_64-apple-darwin)	27m 39s
test (macos-latest, aarch64-apple-darwin)	15m 13s
test (ubuntu-latest, riscv64gc-unknown-linux-gnu, gcc-riscv64-linux-gnu qemu-user)	5m 28s
test (windows-latest, x86_64-pc-windows-gnu)	26m 16s
test (windows-latest, x86_64-pc-windows-msvc)	18m 34s
test (ubuntu-24.04-arm, aarch64-unknown-linux-gnu)	9m 59s
release	12s
	2h 36m 55s

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