Follow-up Comment #18, bug #57538 (project groff): I ported your reproducer to ms, and it doesn't reproduce.
$ cat EXPERIMENTS/need1.ms .mso s.tmac .nr FM 9i .nf 1 .pev .ptr .tm .t=\n[.t] .ne 3 .tm .ne=\n[.ne], .trunc=\n[.trunc], .trap=\n[.trap] 2 3 4 5 6 $ cat EXPERIMENTS/need2.ms .mso s.tmac .nr FM 9i .nf 1 2 .pev .ptr .tm .t=\n[.t] .ne 3 .tm .ne=\n[.ne], .trunc=\n[.trunc], .trap=\n[.trap] 3 4 5 6 $ ./build/test-groff -a EXPERIMENTS/need1.ms >| need1s.out 2>&1 $ ./build/test-groff -a EXPERIMENTS/need2.ms >| need2s.out 2>&1 $ $ diff -u need[12]s.out --- need1s.out 2023-05-18 05:43:03.592759442 -0500 +++ need2s.out 2023-05-18 05:43:11.324731344 -0500 @@ -40,7 +40,7 @@ maximum number of consecutive hyphenated lines: -1 hyphenation space: 0u hyphenation margin: 0u -Environment h: +Environment ne: previous line length: 468000u line length: 468000u previous title length: 468000u @@ -55,7 +55,7 @@ family: 'T' space size: 12/36 em sentence space size: 12/36 em - previous line interrupted: no + previous line interrupted: yes fill mode: on adjust mode: both previous vertical spacing: 12000u @@ -69,7 +69,7 @@ temporary indentation: 0u have temporary indentation: no currently used indentation: 0u - target text length: 0u + target text length: 468000u previous text length: 0u total width: 0u total number of spaces: 0 @@ -77,12 +77,12 @@ line tabs: no discarding: no spread flag set: no - hyphenation_flags: on, not last line, not last two chars + hyphenation_flags: on number of consecutive hyphenated lines: 0 maximum number of consecutive hyphenated lines: -1 hyphenation space: 0u hyphenation margin: 0u -Environment fn: +Environment nf: previous line length: 468000u line length: 468000u previous title length: 468000u @@ -98,10 +98,10 @@ space size: 12/36 em sentence space size: 12/36 em previous line interrupted: no - fill mode: on + fill mode: off adjust mode: both previous vertical spacing: 12000u - vertical spacing: 8000u + vertical spacing: 12000u previous post-vertical spacing: 0u post-vertical spacing: 0u previous line spacing: 1 @@ -124,7 +124,9 @@ maximum number of consecutive hyphenated lines: -1 hyphenation space: 0u hyphenation margin: 0u -Environment ne: +Environment 0: + current +Environment k: previous line length: 468000u line length: 468000u previous title length: 468000u @@ -139,7 +141,7 @@ family: 'T' space size: 12/36 em sentence space size: 12/36 em - previous line interrupted: yes + previous line interrupted: no fill mode: on adjust mode: both previous vertical spacing: 12000u @@ -153,7 +155,7 @@ temporary indentation: 0u have temporary indentation: no currently used indentation: 0u - target text length: 468000u + target text length: 0u previous text length: 0u total width: 0u total number of spaces: 0 @@ -166,7 +168,7 @@ maximum number of consecutive hyphenated lines: -1 hyphenation space: 0u hyphenation margin: 0u -Environment nf: +Environment h: previous line length: 468000u line length: 468000u previous title length: 468000u @@ -182,7 +184,7 @@ space size: 12/36 em sentence space size: 12/36 em previous line interrupted: no - fill mode: off + fill mode: on adjust mode: both previous vertical spacing: 12000u vertical spacing: 12000u @@ -203,14 +205,12 @@ line tabs: no discarding: no spread flag set: no - hyphenation_flags: on + hyphenation_flags: on, not last line, not last two chars number of consecutive hyphenated lines: 0 maximum number of consecutive hyphenated lines: -1 hyphenation space: 0u hyphenation margin: 0u -Environment 0: - current -Environment k: +Environment fn: previous line length: 468000u line length: 468000u previous title length: 468000u @@ -229,7 +229,7 @@ fill mode: on adjust mode: both previous vertical spacing: 12000u - vertical spacing: 12000u + vertical spacing: 8000u previous post-vertical spacing: 0u post-vertical spacing: 0u previous line spacing: 1 @@ -255,7 +255,7 @@ pg@top 0 pg@bottom -648000 pg*footer -324000 -.t=60000 +.t=48000 .ne=0, .trunc=0, .trap=pg@bottom <beginning of page> 1 I don't have any idea which of those environmental differences are red herrings. The environments are getting spat out in a different order, which may be introducing significant noise. _______________________________________________________ Reply to this item at: <https://savannah.gnu.org/bugs/?57538> _______________________________________________ Message sent via Savannah https://savannah.gnu.org/