diff --git a/src/preprocessor.h b/src/preprocessor.h
index 0fdbffb17..26e1d29a9 100644
--- a/src/preprocessor.h
+++ b/src/preprocessor.h
@@ -126,8 +126,16 @@ private:
 
     static std::string getdef(std::string line, bool def);
 
+public:
+    /**
+     * Evaluate condition 'numerically'
+     * @param cfg configuration
+     * @param def condition
+     * @return result when evaluating the condition
+     */
     static bool match_cfg_def(std::string cfg, std::string def);
 
+private:
     /**
      * Search includes from code and append code from the included
      * file
diff --git a/test/testpreprocessor.cpp b/test/testpreprocessor.cpp
index 3cd67f77b..fb24ae1e7 100644
--- a/test/testpreprocessor.cpp
+++ b/test/testpreprocessor.cpp
@@ -86,6 +86,9 @@ private:
 
         TEST_CASE(elif);
 
+        // Test the Preprocessor::match_cfg_def
+        TEST_CASE(match_cfg_def);
+
         TEST_CASE(if_cond1);
         TEST_CASE(if_cond2);
         TEST_CASE(if_cond3);
@@ -518,6 +521,14 @@ private:
 
 
 
+    void match_cfg_def()
+    {
+        TODO_ASSERT_EQUALS(true, Preprocessor::match_cfg_def("A=1", "A==1"));
+        TODO_ASSERT_EQUALS(true, Preprocessor::match_cfg_def("A=1", "A<2"));
+        ASSERT_EQUALS(false, Preprocessor::match_cfg_def("A=1", "A==2"));
+        ASSERT_EQUALS(false, Preprocessor::match_cfg_def("A=1", "A<1"));
+    }
+
 
     void if_cond1()
     {