Resolve clang-tidy warnings, update single_header_generator.py

script/single_header_generator.py

@@ -14,14 +14,21 @@ headers = ['type_traits.hpp',
 
 combined_file = []
 includes = []
+in_pp_block = False
 
 for header in headers:
     with open(headers_dir + header) as f:
         for line in f.read().splitlines():
+            if '#if ' in line:
+                in_pp_block = True
+
+            if '#endif' in line:
+                in_pp_block = False
+
             if '#include "' in line or '#include <fast_float' in line:
                 continue
 
-            if '#include <' in line:
+            if '#include <' in line and not in_pp_block:
                 includes.append(line)
                 continue