"--enable-doc-gen" configure flag will enable HTML document generation that requires mdbook.
We can't simply disable it because we need manpages.

Author: Zhu Zihao <all_but_last@163.com>

--- a/doc/manual/local.mk
+++ b/doc/manual/local.mk
@@ -138,11 +138,6 @@
 	$(trace-gen) $(dummy-env) NIX_PATH=nix/corepkgs=corepkgs $(bindir)/nix __dump-builtins > $@.tmp
 	@mv $@.tmp $@
 
-# Generate the HTML manual.
-.PHONY: manual-html
-manual-html: $(docdir)/manual/index.html
-install: $(docdir)/manual/index.html
-
 # Generate 'nix' manpages.
 install: $(mandir)/man1/nix3-manpages
 man: doc/manual/generated/man1/nix3-manpages
@@ -167,23 +162,4 @@
 	done
 	@touch $@
 
-$(docdir)/manual/index.html: $(MANUAL_SRCS) $(d)/book.toml $(d)/anchors.jq $(d)/custom.css $(d)/src/SUMMARY.md $(d)/src/command-ref/new-cli $(d)/src/contributing/experimental-feature-descriptions.md $(d)/src/command-ref/conf-file.md $(d)/src/language/builtins.md
-	$(trace-gen) \
-		tmp="$$(mktemp -d)"; \
-		cp -r doc/manual "$$tmp"; \
-		find "$$tmp" -name '*.md' | while read -r file; do \
-			$(call process-includes,$$file,$$file); \
-		done; \
-		find "$$tmp" -name '*.md' | while read -r file; do \
-			docroot="$$(realpath --relative-to="$$(dirname "$$file")" $$tmp/manual/src)"; \
-			sed -i "s,@docroot@,$$docroot,g" "$$file"; \
-		done; \
-		set -euo pipefail; \
-		RUST_LOG=warn mdbook build "$$tmp/manual" -d $(DESTDIR)$(docdir)/manual.tmp 2>&1 \
-			| { grep -Fv "because fragment resolution isn't implemented" || :; }; \
-		rm -rf "$$tmp/manual"
-	@rm -rf $(DESTDIR)$(docdir)/manual
-	@mv $(DESTDIR)$(docdir)/manual.tmp/html $(DESTDIR)$(docdir)/manual
-	@rm -rf $(DESTDIR)$(docdir)/manual.tmp
-
 endif
a3a4e80d49dc5d9e3e8f79aa5858783ce9e33'/><select name='qt'>
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<div class='path'>path: <a href='/guix/log/?id=402a3a4e80d49dc5d9e3e8f79aa5858783ce9e33'>root</a>/<a href='/guix/log/gnu?id=402a3a4e80d49dc5d9e3e8f79aa5858783ce9e33'>gnu</a>/<a href='/guix/log/gnu/packages?id=402a3a4e80d49dc5d9e3e8f79aa5858783ce9e33'>packages</a>/<a href='/guix/log/gnu/packages/iso-codes.scm?id=402a3a4e80d49dc5d9e3e8f79aa5858783ce9e33'>iso-codes.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/gnu/packages/iso-codes.scm?id=402a3a4e80d49dc5d9e3e8f79aa5858783ce9e33&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2024-10-02 22:58:39 +0100'>2024-10-02</span></td><td><a href='/guix/commit/gnu/packages/iso-codes.scm?id=308877be17b2c2c92d972e105e8cc6a782ab4c82'>gnu: Add python-country-converter.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/iso-codes.scm (python-country-converter): New variable.

Change-Id: Ib40f94c22b297de02a2ab16b143dcfa59e3a5bdd
Signed-off-by: Sharlatan Hellseher &lt;sharlatanus@gmail.com&gt;
</span></span></td><td>Sharlatan Hellseher</td></tr>
<tr><td><span title='2024-09-28 12:55:54 +0200'>2024-09-28</span></td><td><a href='/guix/commit/gnu/packages/iso-codes.scm?id=2ae666c471fae8a30cb66fdfd47420ff871d89a9'>gnu: Add iso-codes.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/iso-codes.scm (iso-codes): New variable.

Change-Id: I2d945a2daf98d111c04a3c30f0779e39644a5e2e
Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Roman Scherer</td></tr>
<tr><td><span title='2024-09-28 12:55:54 +0200'>2024-09-28</span></td><td><a href='/guix/commit/gnu/packages/iso-codes.scm?id=8e5c8303a414719c19a597247674be87fd500d45'>gnu: iso-codes: Rename to iso-codes/pinned.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/iso-codes.scm (iso-codes): Rename to…
(iso-codes/pinned): … this.
* doc/build.scm,
gnu/installer.scm,
gnu/packages/fcitx.scm,
gnu/packages/fcitx5.scm,
gnu/packages/gnome.scm,
gnu/packages/gstreamer.scm,
gnu/packages/gtk.scm,
gnu/packages/ibus.scm,
gnu/packages/kde-frameworks.scm,
gnu/packages/kde-plasma.scm,
gnu/packages/mate.scm,
gnu/packages/photo.scm,
gnu/packages/video.scm: Adjust accordingly.

Change-Id: Ia98fee15a27009583fee822cf411512727b1aa27
Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Roman Scherer</td></tr>