diff --git a/texlive.spec b/texlive.spec
index 438cd74..17c58be 100644
--- a/texlive.spec
+++ b/texlive.spec
@@ -4137,7 +4137,8 @@ popd
     # Read the options file
     . %{options}
 
-    if test -d /usr/include/unicode -a -d /usr/include/harfbuzz
+    if test -d /usr/include/unicode -a -d /usr/include/harfbuzz && \
+        grep -qrs UBLOCK_LATIN_EXTENDED_F /usr/include/unicode
     then
 	icu[0]='--with-system-icu'
 	icu[1]='--with-system-harfbuzz'