updated build system

support/3rd_party/src/backward.cpp

@@ -1,4 +1,3 @@
-#if defined(PROJECT_ENABLE_BACKWARD_CPP)
 // Pick your poison.
 //
 // On GNU/Linux, you have few choices to get the most out of your stack trace.
@@ -33,12 +32,14 @@
 // - apt-get install libunwind-dev
 // - g++/clang++ -lunwind
 // #define BACKWARD_HAS_LIBUNWIND 1
-
 #include "backward.hpp"
 
+#if defined(PROJECT_ENABLE_BACKWARD_CPP)
+
 namespace backward {
 
 backward::SignalHandling sh;
 
 } // namespace backward
+
 #endif // defined(PROJECT_ENABLE_BACKWARD_CPP)