[llvm-branch-commits] [clang] 63bf5d5 - Revert "[clang] add support for -Wpadded on Windows (#130182)"
via llvm-branch-commits
llvm-branch-commits at lists.llvm.org
Thu Apr 3 05:12:33 PDT 2025
Author: Alex Bradbury
Date: 2025-04-03T13:12:30+01:00
New Revision: 63bf5d531c46cbc9c1571debf285fc51463f007d
URL: https://github.com/llvm/llvm-project/commit/63bf5d531c46cbc9c1571debf285fc51463f007d
DIFF: https://github.com/llvm/llvm-project/commit/63bf5d531c46cbc9c1571debf285fc51463f007d.diff
LOG: Revert "[clang] add support for -Wpadded on Windows (#130182)"
This reverts commit 76fa9530c9ac7f81a49b840556f51f4838efbfe1.
Added:
Modified:
clang/docs/ReleaseNotes.rst
clang/lib/AST/RecordLayoutBuilder.cpp
Removed:
clang/test/SemaCXX/windows-Wpadded-bitfield.cpp
clang/test/SemaCXX/windows-Wpadded.cpp
################################################################################
diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 47f9c3caa0e47..fdf9a246d6373 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -190,8 +190,6 @@ Modified Compiler Flags
- The compiler flag `-fbracket-depth` default value is increased from 256 to 2048. (#GH94728)
-- `-Wpadded` option implemented for the `x86_64-windows-msvc` target. Fixes #61702
-
Removed Compiler Flags
-------------------------
diff --git a/clang/lib/AST/RecordLayoutBuilder.cpp b/clang/lib/AST/RecordLayoutBuilder.cpp
index 41e7198cb7581..3e756ab9b9bfe 100644
--- a/clang/lib/AST/RecordLayoutBuilder.cpp
+++ b/clang/lib/AST/RecordLayoutBuilder.cpp
@@ -2274,9 +2274,9 @@ static unsigned getPaddingDiagFromTagKind(TagTypeKind Tag) {
}
}
-static void CheckFieldPadding(const ASTContext &Context, bool IsUnion,
- uint64_t Offset, uint64_t UnpaddedOffset,
- const FieldDecl *D) {
+void ItaniumRecordLayoutBuilder::CheckFieldPadding(
+ uint64_t Offset, uint64_t UnpaddedOffset, uint64_t UnpackedOffset,
+ unsigned UnpackedAlign, bool isPacked, const FieldDecl *D) {
// We let objc ivars without warning, objc interfaces generally are not used
// for padding tricks.
if (isa<ObjCIvarDecl>(D))
@@ -2300,8 +2300,7 @@ static void CheckFieldPadding(const ASTContext &Context, bool IsUnion,
if (D->getIdentifier()) {
auto Diagnostic = D->isBitField() ? diag::warn_padded_struct_bitfield
: diag::warn_padded_struct_field;
- Context.getDiagnostics().Report(D->getLocation(),
- Diagnostic)
+ Diag(D->getLocation(), Diagnostic)
<< getPaddingDiagFromTagKind(D->getParent()->getTagKind())
<< Context.getTypeDeclType(D->getParent()) << PadSize
<< (InBits ? 1 : 0) // (byte|bit)
@@ -2309,22 +2308,15 @@ static void CheckFieldPadding(const ASTContext &Context, bool IsUnion,
} else {
auto Diagnostic = D->isBitField() ? diag::warn_padded_struct_anon_bitfield
: diag::warn_padded_struct_anon_field;
- Context.getDiagnostics().Report(D->getLocation(),
- Diagnostic)
+ Diag(D->getLocation(), Diagnostic)
<< getPaddingDiagFromTagKind(D->getParent()->getTagKind())
<< Context.getTypeDeclType(D->getParent()) << PadSize
<< (InBits ? 1 : 0); // (byte|bit)
}
- }
-}
-
-void ItaniumRecordLayoutBuilder::CheckFieldPadding(
- uint64_t Offset, uint64_t UnpaddedOffset, uint64_t UnpackedOffset,
- unsigned UnpackedAlign, bool isPacked, const FieldDecl *D) {
- ::CheckFieldPadding(Context, IsUnion, Offset, UnpaddedOffset, D);
- if (isPacked && Offset != UnpackedOffset) {
- HasPackedField = true;
- }
+ }
+ if (isPacked && Offset != UnpackedOffset) {
+ HasPackedField = true;
+ }
}
static const CXXMethodDecl *computeKeyFunction(ASTContext &Context,
@@ -2650,6 +2642,8 @@ struct MicrosoftRecordLayoutBuilder {
/// virtual base classes and their offsets in the record.
ASTRecordLayout::VBaseOffsetsMapTy VBases;
/// The number of remaining bits in our last bitfield allocation.
+ /// This value isn't meaningful unless LastFieldIsNonZeroWidthBitfield is
+ /// true.
unsigned RemainingBitsInField;
bool IsUnion : 1;
/// True if the last field laid out was a bitfield and was not 0
@@ -3010,15 +3004,6 @@ void MicrosoftRecordLayoutBuilder::layoutField(const FieldDecl *FD) {
} else {
FieldOffset = Size.alignTo(Info.Alignment);
}
-
- uint64_t UnpaddedFielddOffsetInBits =
- Context.toBits(DataSize) - RemainingBitsInField;
-
- ::CheckFieldPadding(Context, IsUnion, Context.toBits(FieldOffset),
- UnpaddedFielddOffsetInBits, FD);
-
- RemainingBitsInField = 0;
-
placeFieldAtOffset(FieldOffset);
if (!IsOverlappingEmptyField)
@@ -3064,14 +3049,10 @@ void MicrosoftRecordLayoutBuilder::layoutBitField(const FieldDecl *FD) {
} else {
// Allocate a new block of memory and place the bitfield in it.
CharUnits FieldOffset = Size.alignTo(Info.Alignment);
- uint64_t UnpaddedFieldOffsetInBits =
- Context.toBits(DataSize) - RemainingBitsInField;
placeFieldAtOffset(FieldOffset);
Size = FieldOffset + Info.Size;
Alignment = std::max(Alignment, Info.Alignment);
RemainingBitsInField = Context.toBits(Info.Size) - Width;
- ::CheckFieldPadding(Context, IsUnion, Context.toBits(FieldOffset),
- UnpaddedFieldOffsetInBits, FD);
}
DataSize = Size;
}
@@ -3095,14 +3076,9 @@ MicrosoftRecordLayoutBuilder::layoutZeroWidthBitField(const FieldDecl *FD) {
} else {
// Round up the current record size to the field's alignment boundary.
CharUnits FieldOffset = Size.alignTo(Info.Alignment);
- uint64_t UnpaddedFieldOffsetInBits =
- Context.toBits(DataSize) - RemainingBitsInField;
placeFieldAtOffset(FieldOffset);
- RemainingBitsInField = 0;
Size = FieldOffset;
Alignment = std::max(Alignment, Info.Alignment);
- ::CheckFieldPadding(Context, IsUnion, Context.toBits(FieldOffset),
- UnpaddedFieldOffsetInBits, FD);
}
DataSize = Size;
}
@@ -3227,9 +3203,6 @@ void MicrosoftRecordLayoutBuilder::layoutVirtualBases(const CXXRecordDecl *RD) {
}
void MicrosoftRecordLayoutBuilder::finalizeLayout(const RecordDecl *RD) {
- uint64_t UnpaddedSizeInBits = Context.toBits(DataSize);
- UnpaddedSizeInBits -= RemainingBitsInField;
-
// Respect required alignment. Note that in 32-bit mode Required alignment
// may be 0 and cause size not to be updated.
DataSize = Size;
@@ -3258,22 +3231,6 @@ void MicrosoftRecordLayoutBuilder::finalizeLayout(const RecordDecl *RD) {
Size = Context.toCharUnitsFromBits(External.Size);
if (External.Align)
Alignment = Context.toCharUnitsFromBits(External.Align);
- return;
- }
- unsigned CharBitNum = Context.getTargetInfo().getCharWidth();
- uint64_t SizeInBits = Context.toBits(Size);
- if (SizeInBits > UnpaddedSizeInBits) {
- unsigned int PadSize = SizeInBits - UnpaddedSizeInBits;
- bool InBits = true;
- if (PadSize % CharBitNum == 0) {
- PadSize = PadSize / CharBitNum;
- InBits = false;
- }
-
- Context.getDiagnostics().Report(RD->getLocation(),
- diag::warn_padded_struct_size)
- << Context.getTypeDeclType(RD) << PadSize
- << (InBits ? 1 : 0); // (byte|bit)
}
}
diff --git a/clang/test/SemaCXX/windows-Wpadded-bitfield.cpp b/clang/test/SemaCXX/windows-Wpadded-bitfield.cpp
deleted file mode 100644
index ee5a57124eca5..0000000000000
--- a/clang/test/SemaCXX/windows-Wpadded-bitfield.cpp
+++ /dev/null
@@ -1,32 +0,0 @@
-// RUN: %clang_cc1 -triple x86_64-windows-msvc -fsyntax-only -verify -Wpadded %s
-
-struct __attribute__((ms_struct)) BitfieldStruct { // expected-warning {{padding size of 'BitfieldStruct' with 3 bytes to alignment boundary}}
- char c : 1;
- int : 0; // expected-warning {{padding struct 'BitfieldStruct' with 31 bits to align anonymous bit-field}}
- char i;
-};
-
-struct __attribute__((ms_struct)) SevenBitfieldStruct { // expected-warning {{padding size of 'SevenBitfieldStruct' with 3 bytes to alignment boundary}}
- char c : 7;
- int : 0; // expected-warning {{padding struct 'SevenBitfieldStruct' with 25 bits to align anonymous bit-field}}
- char i;
-};
-
-struct __attribute__((ms_struct)) SameUnitSizeBitfield {
- char c : 7;
- char : 1; // Same unit size attributes fall in the same unit + they fill the unit -> no padding
- char i;
-};
-
-struct __attribute__((ms_struct)) DifferentUnitSizeBitfield { // expected-warning {{padding size of 'DifferentUnitSizeBitfield' with 3 bytes to alignment boundary}}
- char c : 7;
- int : 1; // expected-warning {{padding struct 'DifferentUnitSizeBitfield' with 25 bits to align anonymous bit-field}}
- char i; // expected-warning {{padding struct 'DifferentUnitSizeBitfield' with 31 bits to align 'i'}}
-};
-
-int main() {
- BitfieldStruct b;
- SevenBitfieldStruct s;
- SameUnitSizeBitfield su;
- DifferentUnitSizeBitfield du;
-}
diff --git a/clang/test/SemaCXX/windows-Wpadded.cpp b/clang/test/SemaCXX/windows-Wpadded.cpp
deleted file mode 100644
index da3f2bf08c6b8..0000000000000
--- a/clang/test/SemaCXX/windows-Wpadded.cpp
+++ /dev/null
@@ -1,40 +0,0 @@
-// RUN: %clang_cc1 -triple x86_64-windows-msvc -fsyntax-only -verify -Wpadded %s
-// RUN: %clang_cc1 -triple x86_64-linux-gnu -fsyntax-only -verify -Wpadded %s
-
-struct __attribute__((ms_struct)) Foo { // expected-warning {{padding size of 'Foo' with 3 bytes to alignment boundary}}
- int b : 1;
- char a; // expected-warning {{padding struct 'Foo' with 31 bits to align 'a'}}
-};
-
-struct __attribute__((ms_struct)) AlignedStruct { // expected-warning {{padding size of 'AlignedStruct' with 4 bytes to alignment boundary}}
- char c;
- alignas(8) int i; // expected-warning {{padding struct 'AlignedStruct' with 7 bytes to align 'i'}}
-};
-
-
-struct Base {
- int b;
-};
-
-struct Derived : public Base { // expected-warning {{padding size of 'Derived' with 3 bytes to alignment boundary}}
- char c;
-};
-
-union __attribute__((ms_struct)) Union {
- char c;
- long long u;
-};
-
-struct __attribute__((ms_struct)) StructWithUnion { // expected-warning {{padding size of 'StructWithUnion' with 6 bytes to alignment boundary}}
- char c;
- int : 0;
- Union t; // expected-warning {{padding struct 'StructWithUnion' with 7 bytes to align 't'}}
- short i;
-};
-
-int main() {
- Foo f;
- AlignedStruct a;
- Derived d;
- StructWithUnion swu;
-}
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