Added a config.h file that can be used to permanently enable or disable

asserts when creating a shared library for dlib.

dlib/assert.h

@@ -3,7 +3,7 @@
 #ifndef DLIB_ASSERt_
 #define DLIB_ASSERt_
 
-
+#include "config.h"
 #include <sstream>
 #include <iosfwd>
 #include "error.h"
@@ -49,11 +49,14 @@ namespace dlib
 
 // -----------------------------
 
-#if defined DEBUG || defined _DEBUG
+#if defined DLIB_DISABLE_ASSERTS
+    // if DLIB_DISABLE_ASSERTS is on then never enable DLIB_ASSERT no matter what.
+    #undef ENABLE_ASSERTS
+#endif
+
+#if !defined(DLIB_DISABLE_ASSERTS) && ( defined DEBUG || defined _DEBUG)
     // make sure ENABLE_ASSERTS is defined if we are indeed using them.
-    #ifndef ENABLE_ASSERTS
     #define ENABLE_ASSERTS
-    #endif
 #endif
 
 // -----------------------------

dlib/config.h

+
+
+// If you are compiling dlib as a shared library and installing it somewhere on your system
+// then it is important that any programs that use dlib agree on the state of the
+// DLIB_ASSERT statements (i.e. they are either always on or always off).  Therefore,
+// uncomment one of the following lines to force all DLIB_ASSERTs to either always on or
+// always off.  If you don't define one of these two macros then DLIB_ASSERT will toggle
+// automatically depending on the state of certain other macros, which is not what you want
+// when creating a shared library.
+//#define ENABLE_ASSERTS       // asserts always enabled 
+//#define DLIB_DISABLE_ASSERTS // asserts always disabled 
+