Some cleanup and miri fixes #959

Job	Run time
style	48s
report	20m 55s
build-test (windows-latest, stable, x86_64-pc-windows-msvc, true)	24m 28s
build-test (macos-11, stable, x86_64-apple-darwin, true)	1s
build-test (ubuntu-20.04, stable, x86_64-unknown-linux-gnu, true)	9m 51s
build-test (ubuntu-22.04, stable, x86_64-unknown-linux-gnu, true)	9m 37s
build-test (ubuntu-22.04, stable, i686-unknown-linux-gnu, true)	12m 45s
build-test (ubuntu-22.04, nightly, wasm32-unknown-unknown, true, --no-default-features, --no-run ...	9m 43s
build-test (ubuntu-22.04, 1.77, x86_64-unknown-linux-gnu)	3m 39s
build-test (ubuntu-22.04, beta, x86_64-unknown-linux-gnu)	3m 50s
build-test (ubuntu-22.04, nightly, x86_64-unknown-linux-gnu, true, miri)	4s
logtalk-test	0s
release	0s
	1h 35m 41s

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