r247618 - C11 _Bool bitfield diagnostic

Richard Smith via cfe-commits cfe-commits at lists.llvm.org
Mon Sep 14 21:58:58 PDT 2015


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.
>
The warning we're producing here is for "not all the bits you specified are
part of the value" (or, "this bit-field has padding bits"). I think we
should warn for a bool bitfield with more than 1 bit in C++, just as we
warn on a char bit-field with more than CHAR_BIT bits.

The odd C++ wording about object representation was presumably just to
clarify that this rule was different from the (then-current) C89 standard.

> I would be happy create a patch to make this change tomorrow if people are
> in agreement.
>
> 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>
>
>
>       _______________________________________________
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> *cfe-commits at lists.llvm.org* <cfe-commits at lists.llvm.org>
> *http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits*
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