ftb version bump and small cleanup

.gitignore

@@ -22,3 +22,4 @@ todo.html
 *.svg
 /tests/libslime/main
 /tests/fullslime/main
+*.o

3rd/ftb

@@ -1 +1 @@
-Subproject commit 5519e8640af77da24809d3132a4ce917455f411c
+Subproject commit 6b3c2e157e6717513ff0d4cb7c0146320dfbe02a

src/libslime.cpp

@@ -24,10 +24,11 @@
 #include "ftb/macros.hpp"
 #include "ftb/profiler.hpp"
 
-namespace Slime {
-    struct Lisp_Object;
-}
-
+/*
+  Forward declare the hash functions for the hashmap (needed at least
+  for clang++)
+*/
+namespace Slime {struct Lisp_Object;}
 bool hm_objects_match(char* a, char* b);
 bool hm_objects_match(void* a, void* b);
 bool hm_objects_match(Slime::Lisp_Object* a, Slime::Lisp_Object* b);
@@ -103,7 +104,6 @@ unsigned int hm_hash(Slime::Lisp_Object* obj) {
         return 0;
     }
 }
-#include "ftb/hashmap.hpp"
 
 namespace Slime {
 #    include "globals.cpp"