[bug#74411] [PATCH v2 5/5] gnu: freedict-tools: Fix non-determinism of dictzip compressed file headers.

[Runciter via Guix-patches via <guix-patches@gnu.org>]

Reset .dict file mtime to start of the epoch before compressing with dictzip.

* gnu/packages/patches/freedict-tools-fix-determinism.patch: New file.
* gnu/local.mk (dist_patch_DATA): Add it.
* gnu/packages/dictionaries.scm (freedict-tools): Use it.

Signed-off-by: Runciter <runciter@whispers-vpn.org>
---
 gnu/local.mk                                  |  1 +
 gnu/packages/dictionaries.scm                 |  3 ++-
 .../freedict-tools-fix-determinism.patch      | 22 +++++++++++++++++++
 3 files changed, 25 insertions(+), 1 deletion(-)
 create mode 100644 gnu/packages/patches/freedict-tools-fix-determinism.patch

diff --git a/gnu/local.mk b/gnu/local.mk
index 7004d02547..f6b465441a 100644
--- a/gnu/local.mk
+++ b/gnu/local.mk
@@ -1291,6 +1291,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/fpc-glibc-2.34-compat.patch		\
   %D%/packages/patches/fpm-newer-clamp-fix.patch		\
   %D%/packages/patches/freecad-vtk-9.3.patch		\
+  %D%/packages/patches/freedict-tools-fix-determinism.patch	\
   %D%/packages/patches/freedink-engine-fix-sdl-hints.patch	\
   %D%/packages/patches/freeimage-libtiff-compat.patch		\
   %D%/packages/patches/freeimage-libraw-0.21-compat.patch	\
diff --git a/gnu/packages/dictionaries.scm b/gnu/packages/dictionaries.scm
index 3e5d991890..a6daf209e3 100644
--- a/gnu/packages/dictionaries.scm
+++ b/gnu/packages/dictionaries.scm
@@ -483,7 +483,8 @@ (define-public freedict-tools-0.6.0
              (url "https://github.com/freedict/tools")
              (commit "3596640e6e0582cc5fb76a342e5d8e7413aa4b34")))
        (sha256
-        (base32 "1raayynvn1j8x0ck8pnbbljl6zxnsyzzil7y54xz03dpj7k9w7mk"))))
+        (base32 "1raayynvn1j8x0ck8pnbbljl6zxnsyzzil7y54xz03dpj7k9w7mk"))
+       (patches (search-patches "freedict-tools-fix-determinism.patch"))))
     (inputs (list espeak-ng
                   python
                   perl
diff --git a/gnu/packages/patches/freedict-tools-fix-determinism.patch b/gnu/packages/patches/freedict-tools-fix-determinism.patch
new file mode 100644
index 0000000000..ad100bbba9
--- /dev/null
+++ b/gnu/packages/patches/freedict-tools-fix-determinism.patch
@@ -0,0 +1,22 @@
+The compression utility dictzip writes the compressed file's mtime in a header
+of the compressed file. No command-line switch is documented to control or
+suppress this behavior. This makes the build of packages relying on
+freedict-tools such as freedict-dictionaries non-deterministic.
+
+This patch sets the mtime of the .dict file to be compressed by dictzip to the
+start of the epoch on the Greenwich meridian, restoring build determinism.
+
+diff --git a/mk/dicts.mk b/mk/dicts.mk
+index 08e8923..e671cf3 100644
+--- a/mk/dicts.mk
++++ b/mk/dicts.mk
+@@ -265,7 +265,8 @@ $(BUILD_DICTD)/%.dict $(BUILD_DICTD)/%.index: $(BUILD_DICTD)/%.c5 query-dictd
+ 		dictfmt --without-time -t --headword-separator %%% $(DICTFMTFLAGS) $* < $(notdir $<)
+ 
+ $(BUILD_DICTD)/%.dict.dz: $(BUILD_DICTD)/%.dict
+-	dictzip -k $<
++	touch -m -d "$$(date -u -R -d @0)" $< && \
++		dictzip -k $<
+ 
+ # prevent make from removing our precious file
+ .PRECIOUS: $(BUILD_DICTD)/$(dictname).dict
-- 
2.46.0