This issue was spotted on Ubuntu which builds with LTO by default. I'm
forwarding it here at least for future-proofing. I've reproduced it on
Debian too.

I'm pasting my ubuntu diff below (minus the maintainer change) which
simply adds optimize=-lto to DEB_BUILD_MAINT_OPTIONS. You'll want to
adapt the changelog version and distribution before uploading.


diff -Nru kakoune-2024.05.18/debian/changelog kakoune-2024.05.18/debian/changelog
--- kakoune-2024.05.18/debian/changelog 2024-09-03 15:47:12.000000000 +0200
+++ kakoune-2024.05.18/debian/changelog 2025-01-22 15:56:47.000000000 +0100
@@ -1,3 +1,10 @@
+kakoune (2024.05.18-2ubuntu1) plucky; urgency=medium
+
+  * Add optimize=-lto to DEB_BUILD_MAINT_OPTIONS as LTO builds require
+    more than 17GB of memory and hadn't finished after 30 minutes here
+
+ -- Adrien Nader <adrien.nader@canonical.com>  Wed, 22 Jan 2025 15:56:47 +0100
+
 kakoune (2024.05.18-2) unstable; urgency=medium

   * Fix FTBFS with debhelper 13.17 and later: we override dh_auto_install,
diff -Nru kakoune-2024.05.18/debian/rules kakoune-2024.05.18/debian/rules
--- kakoune-2024.05.18/debian/rules 2024-09-03 15:47:12.000000000 +0200
+++ kakoune-2024.05.18/debian/rules 2025-01-22 15:48:30.000000000 +0100
@@ -1,6 +1,6 @@
 #!/usr/bin/make -f

We believe that the bug you reported is fixed in the latest version of
kakoune, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1093860@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Iliya Abolghasemi <gfaerny@gmail.com> (supplier of updated kakoune package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Tue, 01 Sep 2026 01:14:47 +0330
Source: kakoune
Architecture: source
Version: 2026.05.21-2
Distribution: unstable
Urgency: medium
Maintainer: Iliya Abolghasemi <gfaerny@gmail.com>
Changed-By: Iliya Abolghasemi <gfaerny@gmail.com>
Closes: 1066018 1093860 1143017
Changes:
 kakoune (2026.05.21-2) unstable; urgency=medium
 .
   * New maintainer (Adopt package). Closes: #1143017
   * debian/patches:
     - Drop 03-readme.patch and handle path replacements directly in
       debian/rules recipe.
     - Add 10-docinstall-remove.patch. Closes: #1066018
   * debian/rules:
     - Append optimize=-lto to DEB_BUILD_MAINT_OPTIONS. Closes: #1093860
   * debian/control:
     - Add ${misc:Depends} to binary Depends field to fix Lintian
       debhelper-but-no-misc-depends warning.
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