I ran grep's tests on a debian system this morning and was surprised to see the word-multibyte test fail... Until I realized it was because that system was configured to use dash for /bin/sh, and this test relied on the unportable printf '\xc3\xa1\n' to print an à (A-grave). Using \xHH hexadecimal constants works with bash and zsh, but that is not portable, and dash's printf built-in emits the 9 bytes rather than the expected three.
This isn't the first time this has happened, so I'll be writing a syntax-check rule to help avoid another repeat. Here's how I've fixed it:
0001-maint-move-helper-function-hex_printf-to-init.cfg.patch
Description: Binary data
0002-tests-avoid-printf-xHH-portability-trap.patch
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