Transforms osrm_exception to exception

src/util/exception.cpp

@@ -0,0 +1,21 @@
+#include "util/exception.hpp"
+
+// This function exists to 'anchor' the class, and stop the compiler from
+// copying vtable and RTTI info into every object file that includes
+// this header. (Caught by -Wweak-vtables under Clang.)
+
+// More information from the LLVM Coding Standards:
+// If a class is defined in a header file and has a vtable (either it has
+// virtual methods or it derives from classes with virtual methods), it must
+// always have at least one out-of-line virtual method in the class. Without
+// this, the compiler will copy the vtable and RTTI into every .o file that
+// #includes the header, bloating .o file sizes and increasing link times.
+
+namespace osrm
+{
+namespace util
+{
+
+void exception::anchor() const {}
+}
+}