[Qemu-devel] [PATCH v6 11/16] qapi: Consistent generated code: prefer visitor 'v'

[Eric Blake <eblake@redhat.com>]

We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.

This is patch 2/4, focusing on naming the local visitor variable
'v' rather than 'm'.  Related objects, such as 'QapiDeallocVisitor',
are also named by their initials instead of an unrelated leading m.

No change in semantics to the generated code.

Signed-off-by: Eric Blake <eblake@redhat.com>

---
v6: split 9/46 into four patches, update docs where they are affected,
rebase with 7/46 placed later in series, cover all uses in tree of
"...Visitor *m..."

Signed-off-by: Eric Blake <eblake@redhat.com>
---
 docs/qapi-code-gen.txt   | 74 ++++++++++++++++++++++++------------------------
 qom/object.c             | 18 ++++++------
 qom/qom-qobject.c        | 18 ++++++------
 scripts/qapi-commands.py | 30 ++++++++++----------
 scripts/qapi-types.py    |  8 +++---
 scripts/qapi-visit.py    | 70 ++++++++++++++++++++++-----------------------
 6 files changed, 109 insertions(+), 109 deletions(-)

diff --git a/docs/qapi-code-gen.txt b/docs/qapi-code-gen.txt
index b99e6fa..2afab20 100644
--- a/docs/qapi-code-gen.txt
+++ b/docs/qapi-code-gen.txt
@@ -740,32 +740,32 @@ Example:

     void qapi_free_UserDefOne(UserDefOne *obj)
     {
-        QapiDeallocVisitor *md;
+        QapiDeallocVisitor *qdv;
         Visitor *v;

         if (!obj) {
             return;
         }

-        md = qapi_dealloc_visitor_new();
-        v = qapi_dealloc_get_visitor(md);
+        qdv = qapi_dealloc_visitor_new();
+        v = qapi_dealloc_get_visitor(qdv);
         visit_type_UserDefOne(v, &obj, NULL, NULL);
-        qapi_dealloc_visitor_cleanup(md);
+        qapi_dealloc_visitor_cleanup(qdv);
     }

     void qapi_free_UserDefOneList(UserDefOneList *obj)
     {
-        QapiDeallocVisitor *md;
+        QapiDeallocVisitor *qdv;
         Visitor *v;

         if (!obj) {
             return;
         }

-        md = qapi_dealloc_visitor_new();
-        v = qapi_dealloc_get_visitor(md);
+        qdv = qapi_dealloc_visitor_new();
+        v = qapi_dealloc_get_visitor(qdv);
         visit_type_UserDefOneList(v, &obj, NULL, NULL);
-        qapi_dealloc_visitor_cleanup(md);
+        qapi_dealloc_visitor_cleanup(qdv);
     }
     $ cat qapi-generated/example-qapi-types.h
 [Uninteresting stuff omitted...]
@@ -823,15 +823,15 @@ Example:
     $ cat qapi-generated/example-qapi-visit.c
 [Uninteresting stuff omitted...]

-    static void visit_type_UserDefOne_fields(Visitor *m, UserDefOne **obj, Error **errp)
+    static void visit_type_UserDefOne_fields(Visitor *v, UserDefOne **obj, Error **errp)
     {
         Error *err = NULL;

-        visit_type_int(m, &(*obj)->integer, "integer", &err);
+        visit_type_int(v, &(*obj)->integer, "integer", &err);
         if (err) {
             goto out;
         }
-        visit_type_str(m, &(*obj)->string, "string", &err);
+        visit_type_str(v, &(*obj)->string, "string", &err);
         if (err) {
             goto out;
         }
@@ -840,40 +840,40 @@ Example:
         error_propagate(errp, err);
     }

-    void visit_type_UserDefOne(Visitor *m, UserDefOne **obj, const char *name, Error **errp)
+    void visit_type_UserDefOne(Visitor *v, UserDefOne **obj, const char *name, Error **errp)
     {
         Error *err = NULL;

-        visit_start_struct(m, (void **)obj, "UserDefOne", name, sizeof(UserDefOne), &err);
+        visit_start_struct(v, (void **)obj, "UserDefOne", name, sizeof(UserDefOne), &err);
         if (!err) {
             if (*obj) {
-                visit_type_UserDefOne_fields(m, obj, errp);
+                visit_type_UserDefOne_fields(v, obj, errp);
             }
-            visit_end_struct(m, &err);
+            visit_end_struct(v, &err);
         }
         error_propagate(errp, err);
     }

-    void visit_type_UserDefOneList(Visitor *m, UserDefOneList **obj, const char *name, Error **errp)
+    void visit_type_UserDefOneList(Visitor *v, UserDefOneList **obj, const char *name, Error **errp)
     {
         Error *err = NULL;
         GenericList *i, **prev;

-        visit_start_list(m, name, &err);
+        visit_start_list(v, name, &err);
         if (err) {
             goto out;
         }

         for (prev = (GenericList **)obj;
-             !err && (i = visit_next_list(m, prev, &err)) != NULL;
+             !err && (i = visit_next_list(v, prev, &err)) != NULL;
              prev = &i) {
             UserDefOneList *native_i = (UserDefOneList *)i;
-            visit_type_UserDefOne(m, &native_i->value, NULL, &err);
+            visit_type_UserDefOne(v, &native_i->value, NULL, &err);
         }

         error_propagate(errp, err);
         err = NULL;
-        visit_end_list(m, &err);
+        visit_end_list(v, &err);
     out:
         error_propagate(errp, err);
     }
@@ -885,8 +885,8 @@ Example:

 [Visitors for built-in types omitted...]

-    void visit_type_UserDefOne(Visitor *m, UserDefOne **obj, const char *name, Error **errp);
-    void visit_type_UserDefOneList(Visitor *m, UserDefOneList **obj, const char *name, Error **errp);
+    void visit_type_UserDefOne(Visitor *v, UserDefOne **obj, const char *name, Error **errp);
+    void visit_type_UserDefOneList(Visitor *v, UserDefOneList **obj, const char *name, Error **errp);

     #endif

@@ -917,36 +917,36 @@ Example:
     static void qmp_marshal_output_UserDefOne(UserDefOne *ret_in, QObject **ret_out, Error **errp)
     {
         Error *err = NULL;
-        QmpOutputVisitor *mo = qmp_output_visitor_new();
-        QapiDeallocVisitor *md;
+        QmpOutputVisitor *qov = qmp_output_visitor_new();
+        QapiDeallocVisitor *qdv;
         Visitor *v;

-        v = qmp_output_get_visitor(mo);
+        v = qmp_output_get_visitor(qov);
         visit_type_UserDefOne(v, &ret_in, "unused", &err);
         if (err) {
             goto out;
         }
-        *ret_out = qmp_output_get_qobject(mo);
+        *ret_out = qmp_output_get_qobject(qov);

     out:
         error_propagate(errp, err);
-        qmp_output_visitor_cleanup(mo);
-        md = qapi_dealloc_visitor_new();
-        v = qapi_dealloc_get_visitor(md);
+        qmp_output_visitor_cleanup(qov);
+        qdv = qapi_dealloc_visitor_new();
+        v = qapi_dealloc_get_visitor(qdv);
         visit_type_UserDefOne(v, &ret_in, "unused", NULL);
-        qapi_dealloc_visitor_cleanup(md);
+        qapi_dealloc_visitor_cleanup(qdv);
     }

     static void qmp_marshal_my_command(QDict *args, QObject **ret, Error **errp)
     {
         Error *err = NULL;
         UserDefOne *retval;
-        QmpInputVisitor *mi = qmp_input_visitor_new_strict(QOBJECT(args));
-        QapiDeallocVisitor *md;
+        QmpInputVisitor *qiv = qmp_input_visitor_new_strict(QOBJECT(args));
+        QapiDeallocVisitor *qdv;
         Visitor *v;
         UserDefOne *arg1 = NULL;

-        v = qmp_input_get_visitor(mi);
+        v = qmp_input_get_visitor(qiv);
         visit_type_UserDefOne(v, &arg1, "arg1", &err);
         if (err) {
             goto out;
@@ -961,11 +961,11 @@ Example:

     out:
         error_propagate(errp, err);
-        qmp_input_visitor_cleanup(mi);
-        md = qapi_dealloc_visitor_new();
-        v = qapi_dealloc_get_visitor(md);
+        qmp_input_visitor_cleanup(qiv);
+        qdv = qapi_dealloc_visitor_new();
+        v = qapi_dealloc_get_visitor(qdv);
         visit_type_UserDefOne(v, &arg1, "arg1", NULL);
-        qapi_dealloc_visitor_cleanup(md);
+        qapi_dealloc_visitor_cleanup(qdv);
     }

     static void qmp_init_marshal(void)
diff --git a/qom/object.c b/qom/object.c
index 4805328..11cd86b 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -1167,31 +1167,31 @@ out:
 void object_property_parse(Object *obj, const char *string,
                            const char *name, Error **errp)
 {
-    StringInputVisitor *mi;
-    mi = string_input_visitor_new(string);
-    object_property_set(obj, string_input_get_visitor(mi), name, errp);
+    StringInputVisitor *siv;
+    siv = string_input_visitor_new(string);
+    object_property_set(obj, string_input_get_visitor(siv), name, errp);

-    string_input_visitor_cleanup(mi);
+    string_input_visitor_cleanup(siv);
 }

 char *object_property_print(Object *obj, const char *name, bool human,
                             Error **errp)
 {
-    StringOutputVisitor *mo;
+    StringOutputVisitor *sov;
     char *string = NULL;
     Error *local_err = NULL;

-    mo = string_output_visitor_new(human);
-    object_property_get(obj, string_output_get_visitor(mo), name, &local_err);
+    sov = string_output_visitor_new(human);
+    object_property_get(obj, string_output_get_visitor(sov), name, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
         goto out;
     }

-    string = string_output_get_string(mo);
+    string = string_output_get_string(sov);

 out:
-    string_output_visitor_cleanup(mo);
+    string_output_visitor_cleanup(sov);
     return string;
 }

diff --git a/qom/qom-qobject.c b/qom/qom-qobject.c
index 6384b8e..9649890 100644
--- a/qom/qom-qobject.c
+++ b/qom/qom-qobject.c
@@ -19,11 +19,11 @@
 void object_property_set_qobject(Object *obj, QObject *value,
                                  const char *name, Error **errp)
 {
-    QmpInputVisitor *mi;
-    mi = qmp_input_visitor_new(value);
-    object_property_set(obj, qmp_input_get_visitor(mi), name, errp);
+    QmpInputVisitor *qiv;
+    qiv = qmp_input_visitor_new(value);
+    object_property_set(obj, qmp_input_get_visitor(qiv), name, errp);

-    qmp_input_visitor_cleanup(mi);
+    qmp_input_visitor_cleanup(qiv);
 }

 QObject *object_property_get_qobject(Object *obj, const char *name,
@@ -31,14 +31,14 @@ QObject *object_property_get_qobject(Object *obj, const char *name,
 {
     QObject *ret = NULL;
     Error *local_err = NULL;
-    QmpOutputVisitor *mo;
+    QmpOutputVisitor *qov;

-    mo = qmp_output_visitor_new();
-    object_property_get(obj, qmp_output_get_visitor(mo), name, &local_err);
+    qov = qmp_output_visitor_new();
+    object_property_get(obj, qmp_output_get_visitor(qov), name, &local_err);
     if (!local_err) {
-        ret = qmp_output_get_qobject(mo);
+        ret = qmp_output_get_qobject(qov);
     }
     error_propagate(errp, local_err);
-    qmp_output_visitor_cleanup(mo);
+    qmp_output_visitor_cleanup(qov);
     return ret;
 }
diff --git a/scripts/qapi-commands.py b/scripts/qapi-commands.py
index 2151120..475735d 100644
--- a/scripts/qapi-commands.py
+++ b/scripts/qapi-commands.py
@@ -82,8 +82,8 @@ def gen_marshal_vars(arg_type, ret_type):

     if arg_type:
         ret += mcgen('''
-QmpInputVisitor *mi = qmp_input_visitor_new_strict(QOBJECT(args));
-QapiDeallocVisitor *md;
+QmpInputVisitor *qiv = qmp_input_visitor_new_strict(QOBJECT(args));
+QapiDeallocVisitor *qdv;
 Visitor *v;
 ''')

@@ -122,15 +122,15 @@ def gen_marshal_input_visit(arg_type, dealloc=False):
         errparg = 'NULL'
         errarg = None
         ret += mcgen('''
-qmp_input_visitor_cleanup(mi);
-md = qapi_dealloc_visitor_new();
-v = qapi_dealloc_get_visitor(md);
+qmp_input_visitor_cleanup(qiv);
+qdv = qapi_dealloc_visitor_new();
+v = qapi_dealloc_get_visitor(qdv);
 ''')
     else:
         errparg = '&err'
         errarg = 'err'
         ret += mcgen('''
-v = qmp_input_get_visitor(mi);
+v = qmp_input_get_visitor(qiv);
 ''')

     for memb in arg_type.members:
@@ -160,7 +160,7 @@ visit_type_%(c_type)s(v, &%(c_name)s, "%(name)s", %(errp)s);

     if dealloc:
         ret += mcgen('''
-qapi_dealloc_visitor_cleanup(md);
+qapi_dealloc_visitor_cleanup(qdv);
 ''')
     pop_indent()
     return ret
@@ -172,24 +172,24 @@ def gen_marshal_output(ret_type):
 static void qmp_marshal_output_%(c_name)s(%(c_type)s ret_in, QObject **ret_out, Error **errp)
 {
     Error *err = NULL;
-    QmpOutputVisitor *mo = qmp_output_visitor_new();
-    QapiDeallocVisitor *md;
+    QmpOutputVisitor *qov = qmp_output_visitor_new();
+    QapiDeallocVisitor *qdv;
     Visitor *v;

-    v = qmp_output_get_visitor(mo);
+    v = qmp_output_get_visitor(qov);
     visit_type_%(c_name)s(v, &ret_in, "unused", &err);
     if (err) {
         goto out;
     }
-    *ret_out = qmp_output_get_qobject(mo);
+    *ret_out = qmp_output_get_qobject(qov);

 out:
     error_propagate(errp, err);
-    qmp_output_visitor_cleanup(mo);
-    md = qapi_dealloc_visitor_new();
-    v = qapi_dealloc_get_visitor(md);
+    qmp_output_visitor_cleanup(qov);
+    qdv = qapi_dealloc_visitor_new();
+    v = qapi_dealloc_get_visitor(qdv);
     visit_type_%(c_name)s(v, &ret_in, "unused", NULL);
-    qapi_dealloc_visitor_cleanup(md);
+    qapi_dealloc_visitor_cleanup(qdv);
 }
 ''',
                  c_type=ret_type.c_type(), c_name=ret_type.c_name())
diff --git a/scripts/qapi-types.py b/scripts/qapi-types.py
index b292682..d405f8d 100644
--- a/scripts/qapi-types.py
+++ b/scripts/qapi-types.py
@@ -188,17 +188,17 @@ def gen_type_cleanup(name):

 void qapi_free_%(c_name)s(%(c_name)s *obj)
 {
-    QapiDeallocVisitor *md;
+    QapiDeallocVisitor *qdv;
     Visitor *v;

     if (!obj) {
         return;
     }

-    md = qapi_dealloc_visitor_new();
-    v = qapi_dealloc_get_visitor(md);
+    qdv = qapi_dealloc_visitor_new();
+    v = qapi_dealloc_get_visitor(qdv);
     visit_type_%(c_name)s(v, &obj, NULL, NULL);
-    qapi_dealloc_visitor_cleanup(md);
+    qapi_dealloc_visitor_cleanup(qdv);
 }
 ''',
                 c_name=c_name(name))
diff --git a/scripts/qapi-visit.py b/scripts/qapi-visit.py
index 97343cf..348efe0 100644
--- a/scripts/qapi-visit.py
+++ b/scripts/qapi-visit.py
@@ -24,7 +24,7 @@ def gen_visit_decl(name, scalar=False):
     if not scalar:
         c_type += '*'
     return mcgen('''
-void visit_type_%(c_name)s(Visitor *m, %(c_type)sobj, const char *name, Error **errp);
+void visit_type_%(c_name)s(Visitor *v, %(c_type)sobj, const char *name, Error **errp);
 ''',
                  c_name=c_name(name), c_type=c_type)

@@ -39,20 +39,20 @@ def gen_visit_implicit_struct(typ):
         # Need a forward declaration
         ret += mcgen('''

-static void visit_type_%(c_type)s_fields(Visitor *m, %(c_type)s **obj, Error **errp);
+static void visit_type_%(c_type)s_fields(Visitor *v, %(c_type)s **obj, Error **errp);
 ''',
                      c_type=typ.c_name())

     ret += mcgen('''

-static void visit_type_implicit_%(c_type)s(Visitor *m, %(c_type)s **obj, Error **errp)
+static void visit_type_implicit_%(c_type)s(Visitor *v, %(c_type)s **obj, Error **errp)
 {
     Error *err = NULL;

-    visit_start_implicit_struct(m, (void **)obj, sizeof(%(c_type)s), &err);
+    visit_start_implicit_struct(v, (void **)obj, sizeof(%(c_type)s), &err);
     if (!err) {
-        visit_type_%(c_type)s_fields(m, obj, errp);
-        visit_end_implicit_struct(m, &err);
+        visit_type_%(c_type)s_fields(v, obj, errp);
+        visit_end_implicit_struct(v, &err);
     }
     error_propagate(errp, err);
 }
@@ -71,7 +71,7 @@ def gen_visit_struct_fields(name, base, members):

     ret += mcgen('''

-static void visit_type_%(c_name)s_fields(Visitor *m, %(c_name)s **obj, Error **errp)
+static void visit_type_%(c_name)s_fields(Visitor *v, %(c_name)s **obj, Error **errp)
 {
     Error *err = NULL;

@@ -81,7 +81,7 @@ static void visit_type_%(c_name)s_fields(Visitor *m, %(c_name)s **obj, Error **e

     if base:
         ret += mcgen('''
-visit_type_implicit_%(c_type)s(m, &(*obj)->%(c_name)s, &err);
+visit_type_implicit_%(c_type)s(v, &(*obj)->%(c_name)s, &err);
 if (err) {
     goto out;
 }
@@ -91,14 +91,14 @@ if (err) {
     for memb in members:
         if memb.optional:
             ret += mcgen('''
-visit_optional(m, &(*obj)->has_%(c_name)s, "%(name)s", &err);
+visit_optional(v, &(*obj)->has_%(c_name)s, "%(name)s", &err);
 if (!err && (*obj)->has_%(c_name)s) {
 ''',
                          c_name=c_name(memb.name), name=memb.name)
             push_indent()

         ret += mcgen('''
-visit_type_%(c_type)s(m, &(*obj)->%(c_name)s, "%(name)s", &err);
+visit_type_%(c_type)s(v, &(*obj)->%(c_name)s, "%(name)s", &err);
 ''',
                      c_type=memb.type.c_name(), c_name=c_name(memb.name),
                      name=memb.name)
@@ -136,16 +136,16 @@ def gen_visit_struct(name, base, members):
     # call qapi_free_FOO() to avoid a memory leak of the partial FOO.
     ret += mcgen('''

-void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error **errp)
+void visit_type_%(c_name)s(Visitor *v, %(c_name)s **obj, const char *name, Error **errp)
 {
     Error *err = NULL;

-    visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(c_name)s), &err);
+    visit_start_struct(v, (void **)obj, "%(name)s", name, sizeof(%(c_name)s), &err);
     if (!err) {
         if (*obj) {
-            visit_type_%(c_name)s_fields(m, obj, errp);
+            visit_type_%(c_name)s_fields(v, obj, errp);
         }
-        visit_end_struct(m, &err);
+        visit_end_struct(v, &err);
     }
     error_propagate(errp, err);
 }
@@ -158,26 +158,26 @@ void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error
 def gen_visit_list(name, element_type):
     return mcgen('''

-void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error **errp)
+void visit_type_%(c_name)s(Visitor *v, %(c_name)s **obj, const char *name, Error **errp)
 {
     Error *err = NULL;
     GenericList *i, **prev;

-    visit_start_list(m, name, &err);
+    visit_start_list(v, name, &err);
     if (err) {
         goto out;
     }

     for (prev = (GenericList **)obj;
-         !err && (i = visit_next_list(m, prev, &err)) != NULL;
+         !err && (i = visit_next_list(v, prev, &err)) != NULL;
          prev = &i) {
         %(c_name)s *native_i = (%(c_name)s *)i;
-        visit_type_%(c_elt_type)s(m, &native_i->value, NULL, &err);
+        visit_type_%(c_elt_type)s(v, &native_i->value, NULL, &err);
     }

     error_propagate(errp, err);
     err = NULL;
-    visit_end_list(m, &err);
+    visit_end_list(v, &err);
 out:
     error_propagate(errp, err);
 }
@@ -188,9 +188,9 @@ out:
 def gen_visit_enum(name):
     return mcgen('''

-void visit_type_%(c_name)s(Visitor *m, %(c_name)s *obj, const char *name, Error **errp)
+void visit_type_%(c_name)s(Visitor *v, %(c_name)s *obj, const char *name, Error **errp)
 {
-    visit_type_enum(m, (int *)obj, %(c_name)s_lookup, "%(name)s", name, errp);
+    visit_type_enum(v, (int *)obj, %(c_name)s_lookup, "%(name)s", name, errp);
 }
 ''',
                  c_name=c_name(name), name=name)
@@ -199,15 +199,15 @@ void visit_type_%(c_name)s(Visitor *m, %(c_name)s *obj, const char *name, Error
 def gen_visit_alternate(name, variants):
     ret = mcgen('''

-void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error **errp)
+void visit_type_%(c_name)s(Visitor *v, %(c_name)s **obj, const char *name, Error **errp)
 {
     Error *err = NULL;

-    visit_start_implicit_struct(m, (void**) obj, sizeof(%(c_name)s), &err);
+    visit_start_implicit_struct(v, (void**) obj, sizeof(%(c_name)s), &err);
     if (err) {
         goto out;
     }
-    visit_get_next_type(m, (int*) &(*obj)->kind, %(c_name)s_qtypes, name, &err);
+    visit_get_next_type(v, (int*) &(*obj)->kind, %(c_name)s_qtypes, name, &err);
     if (err) {
         goto out_end;
     }
@@ -218,7 +218,7 @@ void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error
     for var in variants.variants:
         ret += mcgen('''
     case %(case)s:
-        visit_type_%(c_type)s(m, &(*obj)->%(c_name)s, name, &err);
+        visit_type_%(c_type)s(v, &(*obj)->%(c_name)s, name, &err);
         break;
 ''',
                      case=c_enum_const(variants.tag_member.type.name,
@@ -233,7 +233,7 @@ void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error
 out_end:
     error_propagate(errp, err);
     err = NULL;
-    visit_end_implicit_struct(m, &err);
+    visit_end_implicit_struct(v, &err);
 out:
     error_propagate(errp, err);
 }
@@ -256,11 +256,11 @@ def gen_visit_union(name, base, variants):

     ret += mcgen('''

-void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error **errp)
+void visit_type_%(c_name)s(Visitor *v, %(c_name)s **obj, const char *name, Error **errp)
 {
     Error *err = NULL;

-    visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(c_name)s), &err);
+    visit_start_struct(v, (void **)obj, "%(name)s", name, sizeof(%(c_name)s), &err);
     if (err) {
         goto out;
     }
@@ -270,7 +270,7 @@ void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error

     if base:
         ret += mcgen('''
-        visit_type_%(c_name)s_fields(m, obj, &err);
+        visit_type_%(c_name)s_fields(v, obj, &err);
         if (err) {
             goto out_obj;
         }
@@ -282,11 +282,11 @@ void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error
         # we pointlessly use a different key for simple unions
         tag_key = 'type'
     ret += mcgen('''
-        visit_type_%(c_type)s(m, &(*obj)->%(c_name)s, "%(name)s", &err);
+        visit_type_%(c_type)s(v, &(*obj)->%(c_name)s, "%(name)s", &err);
         if (err) {
             goto out_obj;
         }
-        if (!visit_start_union(m, !!(*obj)->data, &err) || err) {
+        if (!visit_start_union(v, !!(*obj)->data, &err) || err) {
             goto out_obj;
         }
         switch ((*obj)->%(c_name)s) {
@@ -308,13 +308,13 @@ void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error
                                        var.name))
         if simple_union_type:
             ret += mcgen('''
-            visit_type_%(c_type)s(m, &(*obj)->%(c_name)s, "data", &err);
+            visit_type_%(c_type)s(v, &(*obj)->%(c_name)s, "data", &err);
 ''',
                          c_type=simple_union_type.c_name(),
                          c_name=c_name(var.name))
         else:
             ret += mcgen('''
-            visit_type_implicit_%(c_type)s(m, &(*obj)->%(c_name)s, &err);
+            visit_type_implicit_%(c_type)s(v, &(*obj)->%(c_name)s, &err);
 ''',
                          c_type=var.type.c_name(),
                          c_name=c_name(var.name))
@@ -329,11 +329,11 @@ void visit_type_%(c_name)s(Visitor *m, %(c_name)s **obj, const char *name, Error
 out_obj:
         error_propagate(errp, err);
         err = NULL;
-        visit_end_union(m, !!(*obj)->data, &err);
+        visit_end_union(v, !!(*obj)->data, &err);
         error_propagate(errp, err);
         err = NULL;
     }
-    visit_end_struct(m, &err);
+    visit_end_struct(v, &err);
 out:
     error_propagate(errp, err);
 }
-- 
2.4.3