diff --git a/configure.ac b/configure.ac
index aeb0d208..76ff45a7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -40,8 +40,8 @@ LX_CFLAGS=${CFLAGS-NONE}
 
 dnl Path check
 
-AS_IF([test pwd | fgrep ' ' > /dev/null 2>&1],
-  [AC_MSG_WARN([The build directory contains whitespaces - This can cause tests/installation to fail due to limitations of some libtool versions])]
+AS_IF([pwd | fgrep ' ' > /dev/null 2>&1],
+  [AC_MSG_ERROR([The build directory contains whitespaces - This can cause tests/installation to fail due to limitations of some libtool versions])]
 )
 
 dnl Switches