Merge 'idl: fix definition order related build failures with clang' from Avi Kivity

Clang eagerly instantiates templates, apparently with the following
algorithm:

 - if both the declaration and definition are seen at the time of
   instantiation, instantiate the template
 - if only the declaration is see at the time of instantiation, just emit
   a reference to the template; even if the definition is later seen,
   it is not instantiated

The "reference" in the second case is a relocation entry in the object file
that is satisfied at link time by the linker, but if no other object file
instantiated the needed template, a link error results.

These problems are hard to diagnose but easy to fix. This series fixes all
known such issues in the code base. It was tested on gcc as well.

Closes #7322

* github.com:scylladb/scylla:
  query-result-reader: order idl implementations correctly
  frozen_schema: order idl implementations correctly
  idl-compiler: generate views after serializers

frozen_schema.cc

@@ -24,10 +24,14 @@
 #include "canonical_mutation.hh"
 #include "schema_mutations.hh"
 #include "idl/uuid.dist.hh"
+#include "idl/keys.dist.hh"
+#include "idl/mutation.dist.hh"
 #include "idl/frozen_schema.dist.hh"
 #include "serializer_impl.hh"
 #include "serialization_visitors.hh"
 #include "idl/uuid.dist.impl.hh"
+#include "idl/keys.dist.impl.hh"
+#include "idl/mutation.dist.impl.hh"
 #include "idl/frozen_schema.dist.impl.hh"
 
 frozen_schema::frozen_schema(const schema_ptr& s)

idl-compiler.py

@@ -1037,9 +1037,9 @@ def load_file(name):
     data = parse_file(name)
     if data:
         handle_types(data)
-    add_visitors(cout)
     if data:
         handle_objects(data, hout, cout)
+    add_visitors(cout)
     if config.ns != '':
         fprintln(cout, "}")
     cout.close()

query-result-reader.hh

@@ -33,9 +33,9 @@
 #include "idl/query.dist.hh"
 #include "serializer_impl.hh"
 #include "serialization_visitors.hh"
-#include "idl/query.dist.impl.hh"
-#include "idl/keys.dist.impl.hh"
 #include "idl/uuid.dist.impl.hh"
+#include "idl/keys.dist.impl.hh"
+#include "idl/query.dist.impl.hh"
 
 namespace query {