diff --git a/glibc.spec b/glibc.spec
index 19a02fb..c161287 100644
--- a/glibc.spec
+++ b/glibc.spec
@@ -1,4 +1,4 @@
-%global glibcsrcdir glibc-2.39.9000-309-ge7ac92e6ca
+%global glibcsrcdir glibc-2.39.9000-355-gdd144dce21
 %global glibcversion 2.39.9000
 # Pre-release tarballs are pulled in from git using a command that is
 # effectively:
@@ -170,7 +170,7 @@ Version: %{glibcversion}
 # - It allows using the Release number without the %%dist tag in the dependency
 #   generator to make the generated requires interchangeable between Rawhide
 #   and ELN (.elnYY < .fcXX).
-%global baserelease 26
+%global baserelease 27
 Release: %{baserelease}%{?dist}
 
 # Licenses:
@@ -824,6 +824,7 @@ local locales =  {
   { code="ln", name="Lingala", regions={ "CD" } },
   { code="lo", name="Lao", regions={ "LA" } },
   { code="lt", name="Lithuanian", regions={ "LT" } },
+  { code="ltg", name="Latgalian", regions={ "LV" } },
   { code="lv", name="Latvian", regions={ "LV" } },
   { code="lzh", name="Literary Chinese", regions={ "TW" } },
   { code="mag", name="Magahi", regions={ "IN" } },
@@ -2560,6 +2561,48 @@ update_gconv_modules_cache ()
 %endif
 
 %changelog
+* Thu Jun 20 2024 Florian Weimer <fweimer@redhat.com> - 2.39.9000-27
+- Auto-sync with upstream branch master,
+  commit dd144dce21c864781fade4561581d50fb4549956:
+- malloc: Replace shell/Perl gate in mtrace
+- s390x: Capture grep output in static PIE check
+- i386: Update ulps
+- malloc: Always install mtrace (bug 31892)
+- Translations: Regenerate libc.pot
+- s390x: Regenerate ULPs.
+- LoongArch: Fix _dl_tlsdesc_dynamic in LSX case
+- aarch64: Update ulps
+- powerpc: Update ulps
+- Linux: Include <dl-symbol-redir-ifunc.h> in dl-sysdep.c
+- linux: add definitions for hugetlb page size encodings
+- elf: Remove HWCAP_IMPORTANT
+- elf: Remove LD_HWCAP_MASK / tunable glibc.cpu.hwcap_mask
+- elf: Remove _DL_PLATFORMS_COUNT
+- elf: Remove _DL_FIRST_PLATFORM
+- elf: Remove _DL_HWCAP_PLATFORM
+- elf: Remove platform strings in dl-procinfo.c
+- elf: Remove _dl_string_platform
+- elf: Remove loading legacy hwcaps/platform entries in dynamic loader
+- x86: Remove HWCAP_START and HWCAP_COUNT
+- math: Update mips32/mips64 ulps for log2p1
+- Convert to autoconf 2.72 (vanilla release, no distribution patches)
+- Implement C23 exp2m1, exp10m1
+- Implement C23 log10p1
+- Implement C23 logp1
+- support: Include <limits.h> for NAME_MAX use in temp_file.c
+- support: Include <stdlib.h> for atoi use in support_wait_for_thread_exit
+- Extend tst-getconf.sh test with NPROCESSORS_CONF and NPROCESSORS_ONLN
+- Define ISO 639-3 "ltg" (Latgalian) and add ltg_LV locale
+- Minor code improvement to timespec_subtract example
+- Modernize and fix doc’s “Date and Time” (BZ 31876)
+- manual: minor language fix (bz 31340)
+- x86: Fix value for `x86_memset_non_temporal_threshold` when it is undesirable
+- elf: Change module-names to modules-names in comments
+- resolv: Track single-request fallback via _res._flags (bug 31476)
+- x86: Properly set x86 minimum ISA level [BZ #31883]
+- tunables: sort tunables list (BZ 30027)
+- linux: Remove __stack_prot
+
 * Wed Jun 12 2024 DJ Delorie <dj@redhat.com> - 2.39.9000-26
 - Auto-sync with upstream branch master,
   commit e7ac92e6ca9784b397189df0b2e1fb34f425bab8.
diff --git a/sources b/sources
index c87d816..e2c9590 100644
--- a/sources
+++ b/sources
@@ -1 +1 @@
-SHA512 (glibc-2.39.9000-309-ge7ac92e6ca.tar.xz) = 9c8d83e6b5dfd90b28c438500c32c0044930c613df6b9d44b0652e096c04af636accde9ff00c97ae8c07f655f850c5dd7cf55006071a1c1d2109630901dceaad
+SHA512 (glibc-2.39.9000-355-gdd144dce21.tar.xz) = 056ca43b7baafa4fff1015fb77371590a3bcaf636a98697f8607741423b11743b7d3462a7a60d0c4c856c10fb7cd723ba1d80abfe0c27a4477b5ee9156b470a3