Only call malloc_usable_size under linux

under OSX `malloc_size` should have the same functionality.

Author: petr-bauch

src/memory-analyzer/gdb_api.cpp

@@ -10,6 +10,11 @@ Author: Malte Mues <[email protected]>
 /// \file
 /// Low-level interface to gdb
 
+#ifdef __linux__
+#  include <malloc.h>
+#elif __APPLE__
+#  include <malloc/malloc.h>
+#endif
 
 #include <cctype>
 #include <cerrno>
@@ -59,7 +64,15 @@ gdb_apit::~gdb_apit()
 
 size_t gdb_apit::query_malloc_size(const std::string &pointer_expr)
 {
+#ifdef __linux__
   write_to_gdb("-var-create tmp * malloc_usable_size(" + pointer_expr + ")");
+#elif __APPLE__
+  write_to_gdb("-var-create tmp * malloc_size(" + pointer_expr + ")");
+#else
+  // Under non-linux/OSX system we simple return 1, i.e. as if the \p
+  // pointer_expr was not dynamically allocated.
+  return 1;
+#endif
 
   if(!was_command_accepted())
   {