r247618 - C11 _Bool bitfield diagnostic
Richard Smith via cfe-commits
cfe-commits at lists.llvm.org
Fri Sep 18 17:06:39 PDT 2015
On Wed, Sep 16, 2015 at 5:33 PM, Richard Smith <richard at metafoo.co.uk>
wrote:
> On Wed, Sep 16, 2015 at 5:27 PM, Nico Weber via cfe-commits <
> cfe-commits at lists.llvm.org> wrote:
>
>> On Tue, Sep 15, 2015 at 5:50 PM, Richard Smith <richard at metafoo.co.uk>
>> wrote:
>>
>>> On Tue, Sep 15, 2015 at 12:38 PM, Nico Weber <thakis at chromium.org>
>>> wrote:
>>>
>>>> With this patch, we warn on `bool a : 4;`, yet we don't warn on `bool
>>>> b` (which has 8 bits storage, 1 bit value). Warning on `bool b` is silly of
>>>> course, but why is warning on `bool a : 4` useful? That's like 50% more
>>>> storage efficient than `bool b` ;-)
>>>>
>>>> It's possible that this is a good warning for some reason, but I don't
>>>> quite see why yet.
>>>>
>>>
>>> Why would we warn on "unsigned n : 57;"? The bit-field is wider than
>>> necessary, and we have no idea what the programmer was trying to do
>>>
>>
>> Warning on this kind of makes sense to me, as the field is wider than the
>> default width of int. (Not warning on that doesn't seem terrible to me
>> either though.)
>>
>> I'm only confused about the bool case with bitfield sizes < 8 I think. We
>> warn that the bitfield is wider than the value size, even though it's
>> smaller than the default storage size, and we don't warn on regular bools.
>>
>> To get an idea how often this warning fires, I ran it on a large-ish open
>> source codebase I had flying around. The only place it fired on is one
>> header in protobuf (extension_set.h). I looked at the history of that file,
>> and it had a struct that used to look like
>>
>> struct Extension {
>> SomeEnum e;
>> bool a;
>> bool b;
>> bool c;
>> int d;
>> // ...some more stuff...
>> };
>>
>> Someone then added another field to this and for some reason decided to
>> do it like so:
>>
>> struct Extension {
>> SomeEnum e;
>> bool a;
>> bool b1 : 4;
>> bool b2 : 4;
>> bool c;
>> int d;
>> // ...some more stuff...
>> };
>>
>> Neither the commit message nor the review discussion mention the bitfield
>> at all as far as I can tell. Now, given that this isn't a small struct and
>> it has a bunch of normal bools, I don't know why they added the new field
>> as bitfield while this wasn't deemed necessary for the existing bools. My
>> best guess is that that they didn't want to add 3 bytes of padding (due to
>> the int field), which seems like a decent reason.
>>
>> Had the warning been in place when this code got written, I suppose they
>> had used ": 1" instead. Does this make this code much better? It doesn't
>> seem like it to me. So after doing a warning quality eval, I'd suggest to
>> not emit the warning for bool bitfields if the bitfield size is < 8. (But
>> since the warning fires only very rarely, I don't feel very strongly about
>> this.)
>>
>
> I agree it doesn't make the code /much/ better. But if I were reading
> that, I would certainly pause for a few moments wondering what the author
> was thinking. I also don't feel especially strongly about this, but I don't
> see a good rationale for warning on 'bool : 9' but not on 'bool : 5'.
>
I'm coming around to the opinion that we shouldn't give this warning on
bool at all -- the point of the warning is to point out that an 'unsigned :
40;' bitfield can't hold 2**40 - 1, and values of that size will be
truncated. There is no corresponding problematic case for bool, so we have
a much weaker justification for warning in this case -- we have no idea
what the user was trying to achieve, but we do not have a signal that their
code is wrong.
Thoughts?
, but it doesn't seem likely they got that effect. Would you be more
>>> convinced if we amended the diagnostic to provide a fixit suggesting using
>>> an anonymous bit-field to insert padding?
>>>
>>
>> Isn't the Right Fix (tm) to make bool bitfields 1 wide and rely on the
>> compiler to figure out padding?
>>
>
> It depends; maybe the intent is to be compatible with some on-disk format,
> and the explicit padding is important:
>
> struct X {
> int n : 3;
> bool b : 3;
> int n : 2;
> };
>
> Changing the bool bit-field to 1 bit without inserting an anonymous
> bit-field would change the struct layout.
>
>
>> On Mon, Sep 14, 2015 at 11:06 PM, Richard Smith <richard at metafoo.co.uk>
>>>> wrote:
>>>>
>>>>> On Mon, Sep 14, 2015 at 7:07 PM, Rachel Craik <rcraik at ca.ibm.com>
>>>>> wrote:
>>>>>
>>>>>> As of DR262, the C standard clarified that the width of a bit-field
>>>>>> can not exceed that of the specified type, and this change was primarily to
>>>>>> ensure that Clang correctly enforced this part of the standard. Looking at
>>>>>> the C++11 standard again, it states that although the specified width of a
>>>>>> bit-field may exceed the number of bits in the *object
>>>>>> representation* (which includes padding bits) of the specified type,
>>>>>> the extra bits will not take any part in the bit-field's *value
>>>>>> representation*.
>>>>>>
>>>>>> Taking this into account, it seems that the correct way to validate
>>>>>> the width of a bit-field (ignoring the special case of MS in C mode) would
>>>>>> be to use getIntWidth in C mode, and getTypeSize in C++ mode.
>>>>>>
>>>>>> I would be happy create a patch to make this change tomorrow if
>>>>>> people are in agreement.
>>>>>>
>>>>> David Majnemer has already landed a couple of changes to fix this up,
>>>>> so hopefully that won't be necessary. Thanks for working on this!
>>>>>
>>>>>> Rachel
>>>>>>
>>>>>>
>>>>>> [image: Inactive hide details for Nico Weber ---09/14/2015 09:53:25
>>>>>> PM---On Mon, Sep 14, 2015 at 5:28 PM, Richard Smith <richard at metafo]Nico
>>>>>> Weber ---09/14/2015 09:53:25 PM---On Mon, Sep 14, 2015 at 5:28 PM, Richard
>>>>>> Smith <richard at metafoo.co.uk> wrote:
>>>>>>
>>>>>> From: Nico Weber <thakis at chromium.org>
>>>>>> To: Richard Smith <richard at metafoo.co.uk>
>>>>>> Cc: Rachel Craik/Toronto/IBM at IBMCA, cfe-commits <
>>>>>> cfe-commits at lists.llvm.org>
>>>>>> Date: 09/14/2015 09:53 PM
>>>>>> Subject: Re: r247618 - C11 _Bool bitfield diagnostic
>>>>>> Sent by: thakis at google.com
>>>>>> ------------------------------
>>>>>>
>>>>>>
>>>>>>
>>>>>> On Mon, Sep 14, 2015 at 5:28 PM, Richard Smith <
>>>>>> *richard at metafoo.co.uk* <richard at metafoo.co.uk>> wrote:
>>>>>>
>>>>>> On Mon, Sep 14, 2015 at 5:18 PM, Nico Weber via cfe-commits <
>>>>>> *cfe-commits at lists.llvm.org* <cfe-commits at lists.llvm.org>> wrote:
>>>>>> This also fires for bool in C++ files, even though the commit
>>>>>> message saying C11 and _Bool. Given the test changes, I suppose that's
>>>>>> intentional? This fires a lot on existing code, for example protobuf:
>>>>>>
>>>>>> ../../third_party/protobuf/src/google/protobuf/extension_set.h:465:10:
>>>>>> error: width of bit-field 'is_cleared' (4 bits) exceeds the width of its
>>>>>> type; value will be truncated to 1 bit [-Werror,-Wbitfield-width]
>>>>>> bool is_cleared : 4;
>>>>>> ^
>>>>>> ../../third_party/protobuf/src/google/protobuf/extension_set.h:472:10:
>>>>>> error: width of bit-field 'is_lazy' (4 bits) exceeds the width of its type;
>>>>>> value will be truncated to 1 bit [-Werror,-Wbitfield-width]
>>>>>> bool is_lazy : 4;
>>>>>> ^
>>>>>>
>>>>>> Is this expected? Is this a behavior change, or did the
>>>>>> truncation happen previously and it's now just getting warned on?
>>>>>>
>>>>>> The code previously assumed that MSVC used the C rules here; it
>>>>>> appears that's not true in all cases.
>>>>>>
>>>>>>
>>>>>> This was on a Mac bot…
>>>>>>
>>>>>>
>>>>>>
>>>>>> Can we just remove the " || IsMsStruct
>>>>>> || Context.getTargetInfo().getCXXABI().isMicrosoft()"? Is there some reason
>>>>>> we need to prohibit overwide bitfields for MS bitfield layout, rather than
>>>>>> just warning on them? (Does record layout fail somehow?)
>>>>>> On Mon, Sep 14, 2015 at 2:27 PM, Rachel Craik via cfe-commits <
>>>>>> *cfe-commits at lists.llvm.org* <cfe-commits at lists.llvm.org>>
>>>>>> wrote:
>>>>>> Author: rcraik
>>>>>> Date: Mon Sep 14 16:27:36 2015
>>>>>> New Revision: 247618
>>>>>>
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project?rev=247618&view=rev*
>>>>>> <http://llvm.org/viewvc/llvm-project?rev=247618&view=rev>
>>>>>> Log:
>>>>>> C11 _Bool bitfield diagnostic
>>>>>>
>>>>>> Summary: Implement DR262 (for C). This patch will mainly
>>>>>> affect bitfields of type _Bool
>>>>>>
>>>>>> Reviewers: fraggamuffin, rsmith
>>>>>>
>>>>>> Subscribers: hubert.reinterpretcast, cfe-commits
>>>>>>
>>>>>> Differential Revision: *http://reviews.llvm.org/D10018*
>>>>>> <http://reviews.llvm.org/D10018>
>>>>>>
>>>>>> Modified:
>>>>>> cfe/trunk/include/clang/Basic/DiagnosticGroups.td
>>>>>> cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
>>>>>> cfe/trunk/lib/Sema/SemaDecl.cpp
>>>>>> cfe/trunk/test/CodeGen/bitfield-2.c
>>>>>> cfe/trunk/test/CodeGenCXX/warn-padded-packed.cpp
>>>>>> cfe/trunk/test/Misc/warning-flags.c
>>>>>> cfe/trunk/test/Sema/bitfield.c
>>>>>> cfe/trunk/test/SemaCXX/bitfield-layout.cpp
>>>>>> cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp
>>>>>> cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp
>>>>>> cfe/trunk/test/SemaCXX/ms_wide_bitfield.cpp
>>>>>> cfe/trunk/test/SemaObjC/class-bitfield.m
>>>>>>
>>>>>> Modified: cfe/trunk/include/clang/Basic/DiagnosticGroups.td
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticGroups.td?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticGroups.td?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/include/clang/Basic/DiagnosticGroups.td
>>>>>> (original)
>>>>>> +++ cfe/trunk/include/clang/Basic/DiagnosticGroups.td Mon
>>>>>> Sep 14 16:27:36 2015
>>>>>> @@ -32,6 +32,7 @@ def AutoImport : DiagGroup<"auto-import"
>>>>>> def GNUBinaryLiteral : DiagGroup<"gnu-binary-literal">;
>>>>>> def GNUCompoundLiteralInitializer :
>>>>>> DiagGroup<"gnu-compound-literal-initializer">;
>>>>>> def BitFieldConstantConversion :
>>>>>> DiagGroup<"bitfield-constant-conversion">;
>>>>>> +def BitFieldWidth : DiagGroup<"bitfield-width">;
>>>>>> def ConstantConversion :
>>>>>> DiagGroup<"constant-conversion", [
>>>>>> BitFieldConstantConversion ] >;
>>>>>> def LiteralConversion : DiagGroup<"literal-conversion">;
>>>>>>
>>>>>> Modified:
>>>>>> cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
>>>>>> (original)
>>>>>> +++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
>>>>>> Mon Sep 14 16:27:36 2015
>>>>>> @@ -4314,20 +4314,21 @@ def err_bitfield_has_negative_width
>>>>>> : Er
>>>>>> def err_anon_bitfield_has_negative_width : Error<
>>>>>> "anonymous bit-field has negative width (%0)">;
>>>>>> def err_bitfield_has_zero_width : Error<"named bit-field
>>>>>> %0 has zero width">;
>>>>>> -def err_bitfield_width_exceeds_type_size : Error<
>>>>>> - "size of bit-field %0 (%1 bits) exceeds size of its type
>>>>>> (%2 bits)">;
>>>>>> -def err_anon_bitfield_width_exceeds_type_size : Error<
>>>>>> - "size of anonymous bit-field (%0 bits) exceeds size of
>>>>>> its type (%1 bits)">;
>>>>>> +def err_bitfield_width_exceeds_type_width : Error<
>>>>>> + "width of bit-field %0 (%1 bits) exceeds width of its
>>>>>> type (%2 bit%s2)">;
>>>>>> +def err_anon_bitfield_width_exceeds_type_width : Error<
>>>>>> + "width of anonymous bit-field (%0 bits) exceeds width of
>>>>>> its type "
>>>>>> + "(%1 bit%s1)">;
>>>>>> def err_incorrect_number_of_vector_initializers : Error<
>>>>>> "number of elements must be either one or match the size
>>>>>> of the vector">;
>>>>>>
>>>>>> // Used by C++ which allows bit-fields that are wider than
>>>>>> the type.
>>>>>> -def warn_bitfield_width_exceeds_type_size: Warning<
>>>>>> - "size of bit-field %0 (%1 bits) exceeds the size of its
>>>>>> type; value will be "
>>>>>> - "truncated to %2 bits">;
>>>>>> -def warn_anon_bitfield_width_exceeds_type_size : Warning<
>>>>>> - "size of anonymous bit-field (%0 bits) exceeds size of
>>>>>> its type; value will "
>>>>>> - "be truncated to %1 bits">;
>>>>>> +def warn_bitfield_width_exceeds_type_width: Warning<
>>>>>> + "width of bit-field %0 (%1 bits) exceeds the width of
>>>>>> its type; value will "
>>>>>> + "be truncated to %2 bit%s2">, InGroup<BitFieldWidth>;
>>>>>> +def warn_anon_bitfield_width_exceeds_type_width : Warning<
>>>>>> + "width of anonymous bit-field (%0 bits) exceeds width of
>>>>>> its type; value "
>>>>>> + "will be truncated to %1 bit%s1">,
>>>>>> InGroup<BitFieldWidth>;
>>>>>>
>>>>>> def warn_missing_braces : Warning<
>>>>>> "suggest braces around initialization of subobject">,
>>>>>>
>>>>>> Modified: cfe/trunk/lib/Sema/SemaDecl.cpp
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/lib/Sema/SemaDecl.cpp (original)
>>>>>> +++ cfe/trunk/lib/Sema/SemaDecl.cpp Mon Sep 14 16:27:36 2015
>>>>>> @@ -12625,26 +12625,26 @@ ExprResult
>>>>>> Sema::VerifyBitField(SourceLo
>>>>>> }
>>>>>>
>>>>>> if (!FieldTy->isDependentType()) {
>>>>>> - uint64_t TypeSize = Context.getTypeSize(FieldTy);
>>>>>> - if (Value.getZExtValue() > TypeSize) {
>>>>>> + uint64_t TypeWidth = Context.getIntWidth(FieldTy);
>>>>>> + if (Value.ugt(TypeWidth)) {
>>>>>> if (!getLangOpts().CPlusPlus || IsMsStruct ||
>>>>>>
>>>>>> Context.getTargetInfo().getCXXABI().isMicrosoft()) {
>>>>>> if (FieldName)
>>>>>> - return Diag(FieldLoc,
>>>>>> diag::err_bitfield_width_exceeds_type_size)
>>>>>> + return Diag(FieldLoc,
>>>>>> diag::err_bitfield_width_exceeds_type_width)
>>>>>> << FieldName << (unsigned)Value.getZExtValue()
>>>>>> - << (unsigned)TypeSize;
>>>>>> + << (unsigned)TypeWidth;
>>>>>>
>>>>>> - return Diag(FieldLoc,
>>>>>> diag::err_anon_bitfield_width_exceeds_type_size)
>>>>>> - << (unsigned)Value.getZExtValue() <<
>>>>>> (unsigned)TypeSize;
>>>>>> + return Diag(FieldLoc,
>>>>>> diag::err_anon_bitfield_width_exceeds_type_width)
>>>>>> + << (unsigned)Value.getZExtValue() <<
>>>>>> (unsigned)TypeWidth;
>>>>>> }
>>>>>>
>>>>>> if (FieldName)
>>>>>> - Diag(FieldLoc,
>>>>>> diag::warn_bitfield_width_exceeds_type_size)
>>>>>> + Diag(FieldLoc,
>>>>>> diag::warn_bitfield_width_exceeds_type_width)
>>>>>> << FieldName << (unsigned)Value.getZExtValue()
>>>>>> - << (unsigned)TypeSize;
>>>>>> + << (unsigned)TypeWidth;
>>>>>> else
>>>>>> - Diag(FieldLoc,
>>>>>> diag::warn_anon_bitfield_width_exceeds_type_size)
>>>>>> - << (unsigned)Value.getZExtValue() <<
>>>>>> (unsigned)TypeSize;
>>>>>> + Diag(FieldLoc,
>>>>>> diag::warn_anon_bitfield_width_exceeds_type_width)
>>>>>> + << (unsigned)Value.getZExtValue() <<
>>>>>> (unsigned)TypeWidth;
>>>>>> }
>>>>>> }
>>>>>>
>>>>>>
>>>>>> Modified: cfe/trunk/test/CodeGen/bitfield-2.c
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/bitfield-2.c?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/bitfield-2.c?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/test/CodeGen/bitfield-2.c (original)
>>>>>> +++ cfe/trunk/test/CodeGen/bitfield-2.c Mon Sep 14 16:27:36
>>>>>> 2015
>>>>>> @@ -237,7 +237,7 @@ unsigned long long test_5() {
>>>>>> /***/
>>>>>>
>>>>>> struct s6 {
>>>>>> - _Bool f0 : 2;
>>>>>> + unsigned f0 : 2;
>>>>>> };
>>>>>>
>>>>>> struct s6 g6 = { 0xF };
>>>>>>
>>>>>> Modified: cfe/trunk/test/CodeGenCXX/warn-padded-packed.cpp
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/warn-padded-packed.cpp?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/warn-padded-packed.cpp?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/test/CodeGenCXX/warn-padded-packed.cpp
>>>>>> (original)
>>>>>> +++ cfe/trunk/test/CodeGenCXX/warn-padded-packed.cpp Mon
>>>>>> Sep 14 16:27:36 2015
>>>>>> @@ -69,7 +69,7 @@ struct S12 {
>>>>>>
>>>>>> struct S13 { // expected-warning {{padding size of 'S13'
>>>>>> with 6 bits to alignment boundary}}
>>>>>> char c;
>>>>>> - bool b : 10; // expected-warning {{size of bit-field 'b'
>>>>>> (10 bits) exceeds the size of its type}}
>>>>>> + bool b : 10; // expected-warning {{width of bit-field
>>>>>> 'b' (10 bits) exceeds the width of its type}}
>>>>>> };
>>>>>>
>>>>>> // The warnings are emitted when the layout of the structs
>>>>>> is computed, so we have to use them.
>>>>>>
>>>>>> Modified: cfe/trunk/test/Misc/warning-flags.c
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Misc/warning-flags.c?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Misc/warning-flags.c?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/test/Misc/warning-flags.c (original)
>>>>>> +++ cfe/trunk/test/Misc/warning-flags.c Mon Sep 14 16:27:36
>>>>>> 2015
>>>>>> @@ -18,7 +18,7 @@ This test serves two purposes:
>>>>>>
>>>>>> The list of warnings below should NEVER grow. It should
>>>>>> gradually shrink to 0.
>>>>>>
>>>>>> -CHECK: Warnings without flags (92):
>>>>>> +CHECK: Warnings without flags (90):
>>>>>> CHECK-NEXT: ext_excess_initializers
>>>>>> CHECK-NEXT:
>>>>>> ext_excess_initializers_in_char_array_initializer
>>>>>> CHECK-NEXT: ext_expected_semi_decl_list
>>>>>> @@ -44,10 +44,8 @@ CHECK-NEXT: pp_pragma_once_in_main_fil
>>>>>> CHECK-NEXT: pp_pragma_sysheader_in_main_file
>>>>>> CHECK-NEXT: w_asm_qualifier_ignored
>>>>>> CHECK-NEXT: warn_accessor_property_type_mismatch
>>>>>> -CHECK-NEXT: warn_anon_bitfield_width_exceeds_type_size
>>>>>> CHECK-NEXT: warn_arcmt_nsalloc_realloc
>>>>>> CHECK-NEXT: warn_asm_label_on_auto_decl
>>>>>> -CHECK-NEXT: warn_bitfield_width_exceeds_type_size
>>>>>> CHECK-NEXT: warn_c_kext
>>>>>> CHECK-NEXT:
>>>>>> warn_call_to_pure_virtual_member_function_from_ctor_dtor
>>>>>> CHECK-NEXT: warn_call_wrong_number_of_arguments
>>>>>>
>>>>>> Modified: cfe/trunk/test/Sema/bitfield.c
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/bitfield.c?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/bitfield.c?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/test/Sema/bitfield.c (original)
>>>>>> +++ cfe/trunk/test/Sema/bitfield.c Mon Sep 14 16:27:36 2015
>>>>>> @@ -6,7 +6,7 @@ struct a {
>>>>>> int a : -1; // expected-error{{bit-field 'a' has
>>>>>> negative width}}
>>>>>>
>>>>>> // rdar://6081627
>>>>>> - int b : 33; // expected-error{{size of bit-field 'b' (33
>>>>>> bits) exceeds size of its type (32 bits)}}
>>>>>> + int b : 33; // expected-error{{width of bit-field 'b'
>>>>>> (33 bits) exceeds width of its type (32 bits)}}
>>>>>>
>>>>>> int c : (1 + 0.25); // expected-error{{expression is not
>>>>>> an integer constant expression}}
>>>>>> int d : (int)(1 + 0.25);
>>>>>> @@ -22,9 +22,12 @@ struct a {
>>>>>> int g : (_Bool)1;
>>>>>>
>>>>>> // PR4017
>>>>>> - char : 10; // expected-error {{size of anonymous
>>>>>> bit-field (10 bits) exceeds size of its type (8 bits)}}
>>>>>> + char : 10; // expected-error {{width of anonymous
>>>>>> bit-field (10 bits) exceeds width of its type (8 bits)}}
>>>>>> unsigned : -2; // expected-error {{anonymous bit-field
>>>>>> has negative width (-2)}}
>>>>>> float : 12; // expected-error {{anonymous bit-field
>>>>>> has non-integral type 'float'}}
>>>>>> +
>>>>>> + _Bool : 2; // expected-error {{width of anonymous
>>>>>> bit-field (2 bits) exceeds width of its type (1 bit)}}
>>>>>> + _Bool h : 5; // expected-error {{width of bit-field 'h'
>>>>>> (5 bits) exceeds width of its type (1 bit)}}
>>>>>> };
>>>>>>
>>>>>> struct b {unsigned x : 2;} x;
>>>>>>
>>>>>> Modified: cfe/trunk/test/SemaCXX/bitfield-layout.cpp
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/bitfield-layout.cpp?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/bitfield-layout.cpp?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/test/SemaCXX/bitfield-layout.cpp (original)
>>>>>> +++ cfe/trunk/test/SemaCXX/bitfield-layout.cpp Mon Sep 14
>>>>>> 16:27:36 2015
>>>>>> @@ -5,25 +5,25 @@
>>>>>>
>>>>>> // Simple tests.
>>>>>> struct Test1 {
>>>>>> - char c : 9; // expected-warning {{size of bit-field 'c'
>>>>>> (9 bits) exceeds the size of its type; value will be truncated to 8 bits}}
>>>>>> + char c : 9; // expected-warning {{width of bit-field 'c'
>>>>>> (9 bits) exceeds the width of its type; value will be truncated to 8 bits}}
>>>>>> };
>>>>>> CHECK_SIZE(Test1, 2);
>>>>>> CHECK_ALIGN(Test1, 1);
>>>>>>
>>>>>> struct Test2 {
>>>>>> - char c : 16; // expected-warning {{size of bit-field 'c'
>>>>>> (16 bits) exceeds the size of its type; value will be truncated to 8 bits}}
>>>>>> + char c : 16; // expected-warning {{width of bit-field
>>>>>> 'c' (16 bits) exceeds the width of its type; value will be truncated to 8
>>>>>> bits}}
>>>>>> };
>>>>>> CHECK_SIZE(Test2, 2);
>>>>>> CHECK_ALIGN(Test2, 2);
>>>>>>
>>>>>> struct Test3 {
>>>>>> - char c : 32; // expected-warning {{size of bit-field 'c'
>>>>>> (32 bits) exceeds the size of its type; value will be truncated to 8 bits}}
>>>>>> + char c : 32; // expected-warning {{width of bit-field
>>>>>> 'c' (32 bits) exceeds the width of its type; value will be truncated to 8
>>>>>> bits}}
>>>>>> };
>>>>>> CHECK_SIZE(Test3, 4);
>>>>>> CHECK_ALIGN(Test3, 4);
>>>>>>
>>>>>> struct Test4 {
>>>>>> - char c : 64; // expected-warning {{size of bit-field 'c'
>>>>>> (64 bits) exceeds the size of its type; value will be truncated to 8 bits}}
>>>>>> + char c : 64; // expected-warning {{width of bit-field
>>>>>> 'c' (64 bits) exceeds the width of its type; value will be truncated to 8
>>>>>> bits}}
>>>>>> };
>>>>>> CHECK_SIZE(Test4, 8);
>>>>>> CHECK_ALIGN(Test4, 8);
>>>>>>
>>>>>> Modified:
>>>>>> cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp
>>>>>> (original)
>>>>>> +++ cfe/trunk/test/SemaCXX/constant-expression-cxx11.cpp
>>>>>> Mon Sep 14 16:27:36 2015
>>>>>> @@ -1801,9 +1801,9 @@ namespace Bitfields {
>>>>>> bool b : 1;
>>>>>> unsigned u : 5;
>>>>>> int n : 5;
>>>>>> - bool b2 : 3;
>>>>>> - unsigned u2 : 74; // expected-warning {{exceeds the
>>>>>> size of its type}}
>>>>>> - int n2 : 81; // expected-warning {{exceeds the size of
>>>>>> its type}}
>>>>>> + bool b2 : 3; // expected-warning {{exceeds the width
>>>>>> of its type}}
>>>>>> + unsigned u2 : 74; // expected-warning {{exceeds the
>>>>>> width of its type}}
>>>>>> + int n2 : 81; // expected-warning {{exceeds the width
>>>>>> of its type}}
>>>>>> };
>>>>>>
>>>>>> constexpr A a = { false, 33, 31, false, 0xffffffff,
>>>>>> 0x7fffffff }; // expected-warning 2{{truncation}}
>>>>>>
>>>>>> Modified:
>>>>>> cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp
>>>>>> (original)
>>>>>> +++ cfe/trunk/test/SemaCXX/constant-expression-cxx1y.cpp
>>>>>> Mon Sep 14 16:27:36 2015
>>>>>> @@ -872,7 +872,7 @@ namespace Lifetime {
>>>>>>
>>>>>> namespace Bitfields {
>>>>>> struct A {
>>>>>> - bool b : 3;
>>>>>> + bool b : 1;
>>>>>> int n : 4;
>>>>>> unsigned u : 5;
>>>>>> };
>>>>>>
>>>>>> Modified: cfe/trunk/test/SemaCXX/ms_wide_bitfield.cpp
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/ms_wide_bitfield.cpp?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/ms_wide_bitfield.cpp?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/test/SemaCXX/ms_wide_bitfield.cpp (original)
>>>>>> +++ cfe/trunk/test/SemaCXX/ms_wide_bitfield.cpp Mon Sep 14
>>>>>> 16:27:36 2015
>>>>>> @@ -1,9 +1,10 @@
>>>>>> // RUN: %clang_cc1 -fno-rtti -emit-llvm-only -triple
>>>>>> i686-pc-win32 -fdump-record-layouts -fsyntax-only -mms-bitfields -verify %s
>>>>>> 2>&1
>>>>>>
>>>>>> struct A {
>>>>>> - char a : 9; // expected-error{{size of bit-field 'a' (9
>>>>>> bits) exceeds size of its type (8 bits)}}
>>>>>> - int b : 33; // expected-error{{size of bit-field 'b' (33
>>>>>> bits) exceeds size of its type (32 bits)}}
>>>>>> - bool c : 9; // expected-error{{size of bit-field 'c' (9
>>>>>> bits) exceeds size of its type (8 bits)}}
>>>>>> + char a : 9; // expected-error{{width of bit-field 'a' (9
>>>>>> bits) exceeds width of its type (8 bits)}}
>>>>>> + int b : 33; // expected-error{{width of bit-field 'b'
>>>>>> (33 bits) exceeds width of its type (32 bits)}}
>>>>>> + bool c : 9; // expected-error{{width of bit-field 'c' (9
>>>>>> bits) exceeds width of its type (1 bit)}}
>>>>>> + bool d : 3; // expected-error{{width of bit-field 'd' (3
>>>>>> bits) exceeds width of its type (1 bit)}}
>>>>>> };
>>>>>>
>>>>>> int a[sizeof(A) == 1 ? 1 : -1];
>>>>>>
>>>>>> Modified: cfe/trunk/test/SemaObjC/class-bitfield.m
>>>>>> URL:
>>>>>> *http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaObjC/class-bitfield.m?rev=247618&r1=247617&r2=247618&view=diff*
>>>>>> <http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaObjC/class-bitfield.m?rev=247618&r1=247617&r2=247618&view=diff>
>>>>>>
>>>>>> ==============================================================================
>>>>>> --- cfe/trunk/test/SemaObjC/class-bitfield.m (original)
>>>>>> +++ cfe/trunk/test/SemaObjC/class-bitfield.m Mon Sep 14
>>>>>> 16:27:36 2015
>>>>>> @@ -5,7 +5,7 @@
>>>>>> int a : -1; // expected-error{{bit-field 'a' has
>>>>>> negative width}}
>>>>>>
>>>>>> // rdar://6081627
>>>>>> - int b : 33; // expected-error{{size of bit-field 'b' (33
>>>>>> bits) exceeds size of its type (32 bits)}}
>>>>>> + int b : 33; // expected-error{{width of bit-field 'b'
>>>>>> (33 bits) exceeds width of its type (32 bits)}}
>>>>>>
>>>>>> int c : (1 + 0.25); // expected-error{{expression is not
>>>>>> an integer constant expression}}
>>>>>> int d : (int)(1 + 0.25);
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> cfe-commits mailing list
>>>>>> *cfe-commits at lists.llvm.org* <cfe-commits at lists.llvm.org>
>>>>>> *http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits*
>>>>>> <http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits>
>>>>>>
>>>>>>
>>>>>> _______________________________________________
>>>>>> cfe-commits mailing list
>>>>>> *cfe-commits at lists.llvm.org* <cfe-commits at lists.llvm.org>
>>>>>> *http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits*
>>>>>> <http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits>
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>
>>>
>>
>> _______________________________________________
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