diff --git a/tests/valgrind.supp b/tests/valgrind.supp
index b800f567da..be0cbe21ce 100644
--- a/tests/valgrind.supp
+++ b/tests/valgrind.supp
@@ -55,3 +55,19 @@
    fun:operate
    fun:main
 }
+
+{
+   libidn-idna_to_ascii-error-inlined-functions-alt
+   Memcheck:Addr4
+   fun:idna_to_ascii_4z
+   fun:idna_to_ascii_8z
+   fun:idna_to_ascii_lz
+   fun:fix_hostname
+   fun:Curl_connect
+   fun:multi_runsingle
+   fun:curl_multi_perform
+   fun:easy_perform
+   fun:operate_do
+   fun:operate
+   fun:main
+}