diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5c56e0abfb910732c219f6e61f0903303ee97407..85b88cf6ecb9169b444d33d677a74f2860a6ddae 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2019-10-16  Jakub Jelinek  <jakub@redhat.com>
+
+	* tree-ssa-strlen.c (maybe_invalidate): Use
+	HOST_WIDE_INT_PRINT_UNSIGNED instead of "%zu".
+
 2019-10-16  Andrew Burgess  <andrew.burgess@embecosm.com>
 	    Jim Wilson  <jimw@sifive.com>
 
diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c
index ff9b92b5b75f9a6c903294c42610686933865128..5c229ca73109ff77ee7c0d81a7d730a483421e5b 100644
--- a/gcc/tree-ssa-strlen.c
+++ b/gcc/tree-ssa-strlen.c
@@ -1130,7 +1130,8 @@ maybe_invalidate (gimple *stmt, bool zero_write = false)
 		  {
 		    if (size && tree_fits_uhwi_p (size))
 		      fprintf (dump_file,
-			       "  statement may clobber string %zu long\n",
+			       "  statement may clobber string "
+			       HOST_WIDE_INT_PRINT_UNSIGNED " long\n",
 			       tree_to_uhwi (size));
 		    else
 		      fprintf (dump_file,