diff --git a/libvips/Makefile.am b/libvips/Makefile.am
index d530f8ad..6cdcbfe8 100644
--- a/libvips/Makefile.am
+++ b/libvips/Makefile.am
@@ -65,6 +65,7 @@ EXTRA_DIST = \
 CLEANFILES = 
 
 all-local:
+	[ -f libvips.la ] && \
 	echo '/* This file is autogenerated, do not edit. */' > soname.h && \
 	source libvips.la && \
 	echo "#define VIPS_SONAME \"$$dlname\"" >> soname.h && \