diff --git a/scripts/qapi.py b/scripts/qapi.py
index 74a561afda..8edfd79c52 100644
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -519,21 +519,6 @@ def check_type(expr_info, source, value, allow_array=False,
                                 'enum'])
 
 
-def check_member_clash(expr_info, base_name, data, source=""):
-    base = find_struct(base_name)
-    assert base
-    base_members = base['data']
-    for key in data.keys():
-        if key.startswith('*'):
-            key = key[1:]
-        if key in base_members or "*" + key in base_members:
-            raise QAPIExprError(expr_info,
-                                "Member name '%s'%s clashes with base '%s'"
-                                % (key, source, base_name))
-    if base.get('base'):
-        check_member_clash(expr_info, base['base'], data, source)
-
-
 def check_command(expr, expr_info):
     name = expr['command']
 
@@ -563,7 +548,6 @@ def check_union(expr, expr_info):
     base = expr.get('base')
     discriminator = expr.get('discriminator')
     members = expr['data']
-    values = {}
 
     # Two types of unions, determined by discriminator.
 
@@ -610,15 +594,9 @@ def check_union(expr, expr_info):
     for (key, value) in members.items():
         check_name(expr_info, "Member of union '%s'" % name, key)
 
-        # Each value must name a known type; furthermore, in flat unions,
-        # branches must be a struct with no overlapping member names
+        # Each value must name a known type
         check_type(expr_info, "Member '%s' of union '%s'" % (key, name),
                    value, allow_array=not base, allow_metas=allow_metas)
-        if base:
-            branch_struct = find_struct(value)
-            assert branch_struct
-            check_member_clash(expr_info, base, branch_struct['data'],
-                               " of branch '%s'" % key)
 
         # If the discriminator names an enum type, then all members
         # of 'data' must also be members of the enum type.
@@ -629,34 +607,16 @@ def check_union(expr, expr_info):
                                     "enum '%s'" %
                                     (key, enum_define["enum_name"]))
 
-        # Otherwise, check for conflicts in the generated enum
-        else:
-            c_key = camel_to_upper(key)
-            if c_key in values:
-                raise QAPIExprError(expr_info,
-                                    "Union '%s' member '%s' clashes with '%s'"
-                                    % (name, key, values[c_key]))
-            values[c_key] = key
-
 
 def check_alternate(expr, expr_info):
     name = expr['alternate']
     members = expr['data']
-    values = {}
     types_seen = {}
 
     # Check every branch
     for (key, value) in members.items():
         check_name(expr_info, "Member of alternate '%s'" % name, key)
 
-        # Check for conflicts in the branch names
-        c_key = c_name(key)
-        if c_key in values:
-            raise QAPIExprError(expr_info,
-                                "Alternate '%s' member '%s' clashes with '%s'"
-                                % (name, key, values[c_key]))
-        values[c_key] = key
-
         # Ensure alternates have no type conflicts.
         check_type(expr_info, "Member '%s' of alternate '%s'" % (key, name),
                    value,
@@ -675,7 +635,6 @@ def check_enum(expr, expr_info):
     name = expr['enum']
     members = expr.get('data')
     prefix = expr.get('prefix')
-    values = {}
 
     if not isinstance(members, list):
         raise QAPIExprError(expr_info,
@@ -686,12 +645,6 @@ def check_enum(expr, expr_info):
     for member in members:
         check_name(expr_info, "Member of enum '%s'" % name, member,
                    enum_member=True)
-        key = camel_to_upper(member)
-        if key in values:
-            raise QAPIExprError(expr_info,
-                                "Enum '%s' member '%s' clashes with '%s'"
-                                % (name, member, values[key]))
-        values[key] = member
 
 
 def check_struct(expr, expr_info):
@@ -702,8 +655,6 @@ def check_struct(expr, expr_info):
                allow_dict=True, allow_optional=True)
     check_type(expr_info, "'base' for struct '%s'" % name, expr.get('base'),
                allow_metas=['struct'])
-    if expr.get('base'):
-        check_member_clash(expr_info, expr['base'], expr['data'])
 
 
 def check_keys(expr_elem, meta, required, optional=[]):
diff --git a/tests/Makefile b/tests/Makefile
index 6b8b11273c..69cef7760d 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -341,7 +341,6 @@ qapi-schema += unclosed-list.json
 qapi-schema += unclosed-object.json
 qapi-schema += unclosed-string.json
 qapi-schema += unicode-str.json
-qapi-schema += union-bad-branch.json
 qapi-schema += union-base-no-discriminator.json
 qapi-schema += union-branch-case.json
 qapi-schema += union-clash-branches.json
diff --git a/tests/qapi-schema/alternate-clash.err b/tests/qapi-schema/alternate-clash.err
index a475ab6343..604d8495eb 100644
--- a/tests/qapi-schema/alternate-clash.err
+++ b/tests/qapi-schema/alternate-clash.err
@@ -1 +1 @@
-tests/qapi-schema/alternate-clash.json:7: Alternate 'Alt1' member 'a_b' clashes with 'a-b'
+tests/qapi-schema/alternate-clash.json:7: 'a_b' (branch of Alt1) collides with 'a-b' (branch of Alt1)
diff --git a/tests/qapi-schema/enum-clash-member.err b/tests/qapi-schema/enum-clash-member.err
index 48bd1360e7..5403c78507 100644
--- a/tests/qapi-schema/enum-clash-member.err
+++ b/tests/qapi-schema/enum-clash-member.err
@@ -1 +1 @@
-tests/qapi-schema/enum-clash-member.json:2: Enum 'MyEnum' member 'ONE' clashes with 'one'
+tests/qapi-schema/enum-clash-member.json:2: 'one_two' (member of MyEnum) collides with 'one-two' (member of MyEnum)
diff --git a/tests/qapi-schema/enum-clash-member.json b/tests/qapi-schema/enum-clash-member.json
index b7dc02a28d..b6928b8bfd 100644
--- a/tests/qapi-schema/enum-clash-member.json
+++ b/tests/qapi-schema/enum-clash-member.json
@@ -1,2 +1,2 @@
 # we reject enums where members will clash when mapped to C enum
-{ 'enum': 'MyEnum', 'data': [ 'one', 'ONE' ] }
+{ 'enum': 'MyEnum', 'data': [ 'one-two', 'one_two' ] }
diff --git a/tests/qapi-schema/flat-union-clash-member.err b/tests/qapi-schema/flat-union-clash-member.err
index 2f0397a8a9..2adf69755a 100644
--- a/tests/qapi-schema/flat-union-clash-member.err
+++ b/tests/qapi-schema/flat-union-clash-member.err
@@ -1 +1 @@
-tests/qapi-schema/flat-union-clash-member.json:11: Member name 'name' of branch 'value1' clashes with base 'Base'
+tests/qapi-schema/flat-union-clash-member.json:11: 'name' (member of Branch1) collides with 'name' (member of Base)
diff --git a/tests/qapi-schema/struct-base-clash-deep.err b/tests/qapi-schema/struct-base-clash-deep.err
index f7a25a3b35..e2d7943f21 100644
--- a/tests/qapi-schema/struct-base-clash-deep.err
+++ b/tests/qapi-schema/struct-base-clash-deep.err
@@ -1 +1 @@
-tests/qapi-schema/struct-base-clash-deep.json:10: Member name 'name' clashes with base 'Base'
+tests/qapi-schema/struct-base-clash-deep.json:10: 'name' (member of Sub) collides with 'name' (member of Base)
diff --git a/tests/qapi-schema/struct-base-clash.err b/tests/qapi-schema/struct-base-clash.err
index 3a9f66b04d..c52f33d27b 100644
--- a/tests/qapi-schema/struct-base-clash.err
+++ b/tests/qapi-schema/struct-base-clash.err
@@ -1 +1 @@
-tests/qapi-schema/struct-base-clash.json:5: Member name 'name' clashes with base 'Base'
+tests/qapi-schema/struct-base-clash.json:5: 'name' (member of Sub) collides with 'name' (member of Base)
diff --git a/tests/qapi-schema/union-bad-branch.err b/tests/qapi-schema/union-bad-branch.err
deleted file mode 100644
index 8822735561..0000000000
--- a/tests/qapi-schema/union-bad-branch.err
+++ /dev/null
@@ -1 +0,0 @@
-tests/qapi-schema/union-bad-branch.json:6: Union 'MyUnion' member 'ONE' clashes with 'one'
diff --git a/tests/qapi-schema/union-bad-branch.exit b/tests/qapi-schema/union-bad-branch.exit
deleted file mode 100644
index d00491fd7e..0000000000
--- a/tests/qapi-schema/union-bad-branch.exit
+++ /dev/null
@@ -1 +0,0 @@
-1
diff --git a/tests/qapi-schema/union-bad-branch.json b/tests/qapi-schema/union-bad-branch.json
deleted file mode 100644
index 913aa38bc8..0000000000
--- a/tests/qapi-schema/union-bad-branch.json
+++ /dev/null
@@ -1,8 +0,0 @@
-# we reject normal unions where branches would collide in C
-{ 'struct': 'One',
-  'data': { 'string': 'str' } }
-{ 'struct': 'Two',
-  'data': { 'number': 'int' } }
-{ 'union': 'MyUnion',
-  'data': { 'one': 'One',
-            'ONE': 'Two' } }
diff --git a/tests/qapi-schema/union-bad-branch.out b/tests/qapi-schema/union-bad-branch.out
deleted file mode 100644
index e69de29bb2..0000000000
diff --git a/tests/qapi-schema/union-clash-branches.err b/tests/qapi-schema/union-clash-branches.err
index 005c48d901..e5b21135bb 100644
--- a/tests/qapi-schema/union-clash-branches.err
+++ b/tests/qapi-schema/union-clash-branches.err
@@ -1 +1 @@
-tests/qapi-schema/union-clash-branches.json:4: Union 'TestUnion' member 'a_b' clashes with 'a-b'
+tests/qapi-schema/union-clash-branches.json:4: 'a_b' (branch of TestUnion) collides with 'a-b' (branch of TestUnion)
diff --git a/tests/qapi-schema/union-clash-branches.json b/tests/qapi-schema/union-clash-branches.json
index 31d135fb17..3bece8c948 100644
--- a/tests/qapi-schema/union-clash-branches.json
+++ b/tests/qapi-schema/union-clash-branches.json
@@ -1,5 +1,5 @@
 # Union branch name collision
 # Reject a union that would result in a collision in generated C names (this
-# would try to generate two enum values 'TEST_UNION_KIND_A_B').
+# would try to generate two members 'a_b').
 { 'union': 'TestUnion',
   'data': { 'a-b': 'int', 'a_b': 'str' } }