Date: Tue, 17 Feb 2026 23:43:39 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 293252] grep(1) hangs when trying to colorize multiple patterns Message-ID: <bug-293252-227@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=293252 Bug ID: 293252 Summary: grep(1) hangs when trying to colorize multiple patterns Product: Base System Version: 14.3-STABLE Hardware: Any OS: Any Status: New Severity: Affects Only Me Priority: --- Component: bin Assignee: bugs@FreeBSD.org Reporter: freebsd@tim.thechases.com To reproduce: $ printf 'one\ntwo\nthree\n' | /usr/bin/grep --color=always -ie ^ -e wo one Expected behavior: It *should* print all lines (everything matches the "^", but as a zero-width atom, not highlight it), highlighting the "wo" in "two". This is how Ubuntu's grep(1) behaves. OpenBSD's grep doesn't support --color so I can't reproduce there. Current behavior: It prints the "one" line then it hangs indefinitely pegging a CPU to 100% according to top(1). Observations: - It works if the second pattern starts at the beginning of a line (searching for "tw" instead of "wo"): $ printf 'one\ntwo\nthree\n' | grep --color=always -i -e '^' -e tw - It works if I don't _also_ search for the beginning of the line: $ printf 'one\ntwo\nthree\n' | grep --color=always -i -e wo - It works if I search for '$' as the first pattern instead: $ printf 'one\ntwo\nthree\n' | grep --color=always -i -e '$' -e wo - It works if I swap the order of the two: $ printf 'one\ntwo\nthree\n' | grep --color=always -i -e wo -e ^ If I remove the `--color=always` it works. $ printf 'one\ntwo\nthree\n' | grep -i -e '^' -e wo So there's something in the interaction of the three (the `^` pattern coming first, a second not-starting-at-the-beginning-of-the-line pattern, and the `--color=always`) that seems to trigger the process-hang/infinite-loop issue. -- You are receiving this mail because: You are the assignee for the bug.home | help
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