diff --git a/CMakeLists.txt b/CMakeLists.txt
index bb616a6..d1fda33 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -378,6 +378,10 @@
   SET(HAVE_ALLOCA 0)
   SET(C_ALLOCA 0)
   CHECK_INCLUDE_FILE( "alloca.h" HAVE_ALLOCA_H )
+ELSE (NOT HAVE_ALLOCA)
+  SET(HAVE_ALLOCA 1)
+  SET(C_ALLOCA 1)
+  SET(HAVE_ALLOCA_H 0)
 ENDIF (NOT HAVE_ALLOCA)
 
 #