Remove blink style presubmit check about mixing unsigned and bool bitfields.

Since we don't support MSVC, and since it seems that's the only compiler
that causes inefficient packing, I think we can remove the presubmit check
that enforces no mixing of unsigned and bool bitfields.

R=pdr@chromium.org, wangxianzhu@chromium.org

Change-Id: I176bded0da8fe5430029044ff96ec497ee28b999
Reviewed-on: https://chromium-review.googlesource.com/1250051Reviewed-by: Philip Rogers <pdr@chromium.org>
Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Commit-Queue: vmpstr <vmpstr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#594901}

third_party/blink/tools/blinkpy/style/checkers/cpp.py

@@ -1123,16 +1123,6 @@ def check_for_non_standard_constructs(clean_lines, line_number,
                   'The class %s probably needs a virtual destructor due to '
                   'having virtual method(s), one declared at line %d.'
                   % (classinfo.name, classinfo.virtual_method_line_number))
-        # Look for mixed bool and unsigned bitfields.
-        if classinfo.bool_bitfields and classinfo.unsigned_bitfields:
-            bool_list = ', '.join(classinfo.bool_bitfields)
-            unsigned_list = ', '.join(classinfo.unsigned_bitfields)
-            error(classinfo.line_number, 'runtime/bitfields', 5,
-                  'The class %s contains mixed unsigned and bool bitfields, '
-                  'which will pack into separate words on the MSVC compiler.\n'
-                  'Bool bitfields are [%s].\nUnsigned bitfields are [%s].\n'
-                  'Consider converting bool bitfields to unsigned.'
-                  % (classinfo.name, bool_list, unsigned_list))
     else:
         classinfo.brace_depth = brace_depth
 

third_party/blink/tools/blinkpy/style/checkers/cpp_unittest.py

@@ -1506,51 +1506,6 @@ class CppStyleTest(CppStyleTestBase):
         self.assert_lint('long int a : 30;', errmsg)
         self.assert_lint('int a = 1 ? 0 : 30;', '')
 
-    # A mixture of unsigned and bool bitfields in a class will generate a warning.
-    def test_mixing_unsigned_bool_bitfields(self):
-        def errmsg(bool_bitfields, unsigned_bitfields, name):
-            bool_list = ', '.join(bool_bitfields)
-            unsigned_list = ', '.join(unsigned_bitfields)
-            return ('The class %s contains mixed unsigned and bool bitfields, '
-                    'which will pack into separate words on the MSVC compiler.\n'
-                    'Bool bitfields are [%s].\nUnsigned bitfields are [%s].\n'
-                    'Consider converting bool bitfields to unsigned.  [runtime/bitfields] [5]'
-                    % (name, bool_list, unsigned_list))
-
-        def build_test_case(bitfields, name, will_warn, extra_warnings=None):
-            bool_bitfields = []
-            unsigned_bitfields = []
-            test_string = 'class %s {\n' % (name,)
-            line = 2
-            for bitfield in bitfields:
-                test_string += '    %s %s : %d;\n' % bitfield
-                if bitfield[0] == 'bool':
-                    bool_bitfields.append('%d: %s' % (line, bitfield[1]))
-                elif bitfield[0].startswith('unsigned'):
-                    unsigned_bitfields.append('%d: %s' % (line, bitfield[1]))
-                line += 1
-            test_string += '}\n'
-            error = ''
-            if will_warn:
-                error = errmsg(bool_bitfields, unsigned_bitfields, name)
-            if extra_warnings and error:
-                error = extra_warnings + [error]
-            self.assert_multi_line_lint(test_string, error)
-
-        build_test_case([('bool', 'm_boolMember', 4), ('unsigned', 'm_unsignedMember', 3)],
-                        'MyClass', True)
-        build_test_case([('bool', 'm_boolMember', 4), ('bool', 'm_anotherBool', 3)],
-                        'MyClass', False)
-        build_test_case([('unsigned', 'm_unsignedMember', 4), ('unsigned', 'm_anotherUnsigned', 3)],
-                        'MyClass', False)
-
-        self.assert_multi_line_lint('class NoProblemsHere {\n'
-                                    '  bool m_boolMember;\n'
-                                    '  unsigned m_unsignedMember;\n'
-                                    '  unsigned m_bitField1 : 1;\n'
-                                    '  unsigned m_bitField4 : 4;\n'
-                                    '}\n', '')
-
     # Bitfields which are not declared unsigned or bool will generate a warning.
     def test_unsigned_bool_bitfields(self):
         def errmsg(member, name, bit_type):