This patch is taken from debian's glibc package (generate-supported.mk).
It install the localedata/SUPPORTED file of the glibc. This file lists
all the supported locales of the glibc.

diff --git a/localedata/Makefile.old b/localedata/Makefile
index 34877c0..a61d9b9 100644
--- a/localedata/Makefile.old
+++ b/localedata/Makefile
@@ -91,7 +91,8 @@ endif
 # Files to install.
 install-others := $(addprefix $(inst_i18ndir)/, \
 			      $(addsuffix .gz, $(charmaps)) \
-			      $(locales))
+			      $(locales)) \
+                   $(inst_i18ndir)/SUPPORTED
 
 tests: $(objdir)/iconvdata/gconv-modules
 
@@ -195,6 +196,14 @@ endif
 
 include SUPPORTED
 
+$(inst_i18ndir)/SUPPORTED: SUPPORTED $(+force)
+	for locale in $(SUPPORTED-LOCALES); do \
+		[ $$locale = true ] && continue; \
+		echo $$locale | sed 's,/, ,' >> LOCALES; \
+	done
+	$(make-target-directory)
+	$(INSTALL_DATA) LOCALES $@
+
 INSTALL-SUPPORTED-LOCALES=$(addprefix install-, $(SUPPORTED-LOCALES))
 
 # Sometimes the whole collection of locale files should be installed.
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<tr><td><span title='2024-01-09 09:38:38 +0200'>2024-01-09</span></td><td><a href='/guix/commit/tests/crate.scm?id=b26926189e5bf253093050f9a73f2d9d7555cc3e'>guix: import: Optionally import necessary yanked crates.</a><span class='msg-avail'>...</span></td><td>David Elsing</td></tr>
<tr><td><span title='2024-01-09 09:38:38 +0200'>2024-01-09</span></td><td><a href='/guix/commit/tests/crate.scm?id=53add91be621a9d97e534397f16f71e071eaba96'>tests: Mock find-packages-by-name in crate importer test.</a><span class='msg-avail'>...</span></td><td>David Elsing</td></tr>
<tr><td><span title='2024-01-09 09:38:38 +0200'>2024-01-09</span></td><td><a href='/guix/commit/tests/crate.scm?id=9f44ff2bb47c964d53905cea17c4bda758cce509'>import: crate: Optionally import dev-dependencies recursively.</a><span class='msg-avail'>...</span></td><td>David Elsing</td></tr>
<tr><td><span title='2023-10-22 16:46:39 +0300'>2023-10-22</span></td><td><a href='/guix/commit/tests/crate.scm?id=742554f9b973610a54ada9dee2971939cc36ddd7'>guix: import: Don't import yanked rust crates.</a><span class='msg-avail'>...</span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2022-05-30 16:34:39 +0200'>2022-05-30</span></td><td><a href='/guix/commit/tests/crate.scm?id=61d4f9e89da8471ecf4df93ab25c0d707797122a'>tests: Adjust crate importer test to spdx changes.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>