diff --git a/README.md b/README.md
index b3450a8e3358f04bcab2368d088283c843d18c2a..34fb787d7884fc242818bf2b44291dffd6cc233b 100644
--- a/README.md
+++ b/README.md
@@ -9,6 +9,9 @@ Compilation
 
 Just do `make`. Requires Cython >= 0.17.
 
+To compile with nondefault options use i.e. `CXXFLAGS="-DSAVE_MEMORY=0" make`
+to turn off `SAVE_MEMORY`. For list of options see file `compileTimeOptions.h`.
+
 Usage
 -----
 
diff --git a/compileTimeOptions.h b/compileTimeOptions.h
index b7669fcc1faa1bf557717232cc111ea57ebbffff..6b47bc0fb482ae0b53cc42f5c31f775495deca5a 100644
--- a/compileTimeOptions.h
+++ b/compileTimeOptions.h
@@ -5,7 +5,11 @@
 #ifndef SAVE_MEMORY
 #define SAVE_MEMORY 1
 #endif
-
+#if SAVE_MEMORY
+#pragma message "SAVE_MEMORY ON"
+#else
+#pragma message "SAVE_MEMORY off"
+#endif
 
 #endif