diff --git a/debian/changelog b/debian/changelog
index 887297ec..3109171d 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,9 @@
+llvm-toolchain-18 (1:18.1.0~rc2-3) unstable; urgency=medium
+
+  * Add abi=+time64,+lfs only on 64bits system
+
+ -- Sylvestre Ledru <sylvestre@debian.org>  Sun, 11 Feb 2024 14:29:31 +0100
+
 llvm-toolchain-18 (1:18.1.0~rc2-2) unstable; urgency=medium
 
   [ Gianfranco Costamagna ]
diff --git a/debian/rules b/debian/rules
index 00a2432a..7f060988 100755
--- a/debian/rules
+++ b/debian/rules
@@ -66,7 +66,12 @@ CONFIGURE_EXTRA =
 # dpkg-buildflags support
 # disable fixfilepath in favor of the llvm-project supplied flavor, disable lto
 # remove +time64,+lfs once the time64_t transition starts
-export DEB_BUILD_MAINT_OPTIONS = reproducible=-fixfilepath,-fixdebugpath optimize=-lto abi=+time64,+lfs
+export DEB_BUILD_MAINT_OPTIONS = reproducible=-fixfilepath,-fixdebugpath optimize=-lto
+
+ifeq ($(DEB_BUILD_ARCH_BITS),64)
+    export DEB_BUILD_MAINT_OPTIONS += abi=+time64,+lfs
+endif
+
 
 # these are handled on a per stage / build basis
 ifeq ($(VENDOR)-$(DEB_HOST_ARCH),Ubuntu-ppc64el)