diff --git a/libs/freetdm/acinclude.m4 b/libs/freetdm/acinclude.m4
index 908ddba855..097278b6ef 100644
--- a/libs/freetdm/acinclude.m4
+++ b/libs/freetdm/acinclude.m4
@@ -1 +1,2 @@
+m4_include([build/ax_compiler_vendor.m4])
 m4_include([build/libpcap.m4])