[clang] 1594413 - Add Clang attribute to ensure that fields are initialized explicitly (#102040)
via cfe-commits
cfe-commits at lists.llvm.org
Tue Jan 14 10:31:16 PST 2025
Author: higher-performance
Date: 2025-01-14T13:31:12-05:00
New Revision: 1594413d5edf6a47d4100cb6a2bc613cfbb92beb
URL: https://github.com/llvm/llvm-project/commit/1594413d5edf6a47d4100cb6a2bc613cfbb92beb
DIFF: https://github.com/llvm/llvm-project/commit/1594413d5edf6a47d4100cb6a2bc613cfbb92beb.diff
LOG: Add Clang attribute to ensure that fields are initialized explicitly (#102040)
This is a new Clang-specific attribute to ensure that field
initializations are performed explicitly.
For example, if we have
```
struct B {
[[clang::explicit]] int f1;
};
```
then the diagnostic would trigger if we do `B b{};`:
```
field 'f1' is left uninitialized, but was marked as requiring initialization
```
This prevents callers from accidentally forgetting to initialize fields,
particularly when new fields are added to the class.
Added:
Modified:
clang/include/clang/AST/Decl.h
clang/include/clang/AST/DeclBase.h
clang/include/clang/Basic/Attr.td
clang/include/clang/Basic/AttrDocs.td
clang/include/clang/Basic/DiagnosticASTKinds.td
clang/include/clang/Basic/DiagnosticGroups.td
clang/include/clang/Basic/DiagnosticSemaKinds.td
clang/lib/AST/Decl.cpp
clang/lib/AST/DeclCXX.cpp
clang/lib/Sema/SemaDecl.cpp
clang/lib/Sema/SemaInit.cpp
clang/lib/Serialization/ASTReaderDecl.cpp
clang/lib/Serialization/ASTWriterDecl.cpp
clang/test/Misc/pragma-attribute-supported-attributes-list.test
clang/test/Sema/uninit-variables.c
clang/test/SemaCXX/uninitialized.cpp
Removed:
################################################################################
diff --git a/clang/include/clang/AST/Decl.h b/clang/include/clang/AST/Decl.h
index 9c470f09406378..27a91a2d07210b 100644
--- a/clang/include/clang/AST/Decl.h
+++ b/clang/include/clang/AST/Decl.h
@@ -4285,6 +4285,14 @@ class RecordDecl : public TagDecl {
RecordDeclBits.HasNonTrivialToPrimitiveCopyCUnion = V;
}
+ bool hasUninitializedExplicitInitFields() const {
+ return RecordDeclBits.HasUninitializedExplicitInitFields;
+ }
+
+ void setHasUninitializedExplicitInitFields(bool V) {
+ RecordDeclBits.HasUninitializedExplicitInitFields = V;
+ }
+
/// Determine whether this class can be passed in registers. In C++ mode,
/// it must have at least one trivial, non-deleted copy or move constructor.
/// FIXME: This should be set as part of completeDefinition.
diff --git a/clang/include/clang/AST/DeclBase.h b/clang/include/clang/AST/DeclBase.h
index 77abd8b657a616..1c48c91bbe5a46 100644
--- a/clang/include/clang/AST/DeclBase.h
+++ b/clang/include/clang/AST/DeclBase.h
@@ -1446,6 +1446,9 @@ class DeclContext {
/// hasLazyLocalLexicalLookups, hasLazyExternalLexicalLookups
friend class ASTWriter;
+protected:
+ enum { NumOdrHashBits = 25 };
+
// We use uint64_t in the bit-fields below since some bit-fields
// cross the unsigned boundary and this breaks the packing.
@@ -1667,6 +1670,14 @@ class DeclContext {
LLVM_PREFERRED_TYPE(bool)
uint64_t HasNonTrivialToPrimitiveCopyCUnion : 1;
+ /// True if any field is marked as requiring explicit initialization with
+ /// [[clang::requires_explicit_initialization]].
+ /// In C++, this is also set for types without a user-provided default
+ /// constructor, and is propagated from any base classes and/or member
+ /// variables whose types are aggregates.
+ LLVM_PREFERRED_TYPE(bool)
+ uint64_t HasUninitializedExplicitInitFields : 1;
+
/// Indicates whether this struct is destroyed in the callee.
LLVM_PREFERRED_TYPE(bool)
uint64_t ParamDestroyedInCallee : 1;
@@ -1681,7 +1692,7 @@ class DeclContext {
/// True if a valid hash is stored in ODRHash. This should shave off some
/// extra storage and prevent CXXRecordDecl to store unused bits.
- uint64_t ODRHash : 26;
+ uint64_t ODRHash : NumOdrHashBits;
};
/// Number of inherited and non-inherited bits in RecordDeclBitfields.
diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
index a752d94b06fad6..b7d9357e1b4e18 100644
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -1902,6 +1902,13 @@ def Leaf : InheritableAttr {
let SimpleHandler = 1;
}
+def ExplicitInit : InheritableAttr {
+ let Spellings = [Clang<"requires_explicit_initialization">];
+ let Subjects = SubjectList<[Field], ErrorDiag>;
+ let Documentation = [ExplicitInitDocs];
+ let SimpleHandler = 1;
+}
+
def LifetimeBound : DeclOrTypeAttr {
let Spellings = [Clang<"lifetimebound", 0>];
let Subjects = SubjectList<[ParmVar, ImplicitObjectParameter], ErrorDiag>;
diff --git a/clang/include/clang/Basic/AttrDocs.td b/clang/include/clang/Basic/AttrDocs.td
index e10f24e239eceb..b949a105e13317 100644
--- a/clang/include/clang/Basic/AttrDocs.td
+++ b/clang/include/clang/Basic/AttrDocs.td
@@ -1684,6 +1684,55 @@ is not specified.
}];
}
+def ExplicitInitDocs : Documentation {
+ let Category = DocCatField;
+ let Content = [{
+The ``clang::requires_explicit_initialization`` attribute indicates that a
+field of an aggregate must be initialized explicitly by the user when an object
+of the aggregate type is constructed. The attribute supports both C and C++,
+but its usage is invalid on non-aggregates.
+
+Note that this attribute is *not* a memory safety feature, and is *not* intended
+to guard against use of uninitialized memory.
+
+Rather, it is intended for use in "parameter-objects", used to simulate,
+for example, the passing of named parameters.
+The attribute generates a warning when explicit initializers for such
+variables are not provided (this occurs regardless of whether any in-class field
+initializers exist):
+
+.. code-block:: c++
+
+ struct Buffer {
+ void *address [[clang::requires_explicit_initialization]];
+ size_t length [[clang::requires_explicit_initialization]] = 0;
+ };
+
+ struct ArrayIOParams {
+ size_t count [[clang::requires_explicit_initialization]];
+ size_t element_size [[clang::requires_explicit_initialization]];
+ int flags = 0;
+ };
+
+ size_t ReadArray(FILE *file, struct Buffer buffer,
+ struct ArrayIOParams params);
+
+ int main() {
+ unsigned int buf[512];
+ ReadArray(stdin, {
+ buf
+ // warning: field 'length' is not explicitly initialized
+ }, {
+ .count = sizeof(buf) / sizeof(*buf),
+ // warning: field 'element_size' is not explicitly initialized
+ // (Note that a missing initializer for 'flags' is not diagnosed, because
+ // the field is not marked as requiring explicit initialization.)
+ });
+ }
+
+ }];
+}
+
def NoUniqueAddressDocs : Documentation {
let Category = DocCatField;
let Content = [{
diff --git a/clang/include/clang/Basic/DiagnosticASTKinds.td b/clang/include/clang/Basic/DiagnosticASTKinds.td
index ab432606edbc4c..ac53778339a20d 100644
--- a/clang/include/clang/Basic/DiagnosticASTKinds.td
+++ b/clang/include/clang/Basic/DiagnosticASTKinds.td
@@ -396,6 +396,16 @@ def note_constexpr_assumption_failed : Note<
def err_experimental_clang_interp_failed : Error<
"the experimental clang interpreter failed to evaluate an expression">;
+def warn_attribute_needs_aggregate : Warning<
+ "%0 attribute is ignored in non-aggregate type %1">,
+ InGroup<IgnoredAttributes>;
+
+def warn_cxx20_compat_requires_explicit_init_non_aggregate : Warning<
+ "explicit initialization of field %1 will not be enforced in C++20 and later "
+ "because %2 has a user-declared constructor, making the type no longer an "
+ "aggregate">,
+ DefaultIgnore, InGroup<CXX20Compat>;
+
def warn_integer_constant_overflow : Warning<
"overflow in expression; result is %0 with type %1">,
InGroup<DiagGroup<"integer-overflow">>;
diff --git a/clang/include/clang/Basic/DiagnosticGroups.td b/clang/include/clang/Basic/DiagnosticGroups.td
index 594e99a19b64d6..b0ad76026fdb35 100644
--- a/clang/include/clang/Basic/DiagnosticGroups.td
+++ b/clang/include/clang/Basic/DiagnosticGroups.td
@@ -796,6 +796,7 @@ def Trigraphs : DiagGroup<"trigraphs">;
def UndefinedReinterpretCast : DiagGroup<"undefined-reinterpret-cast">;
def ReinterpretBaseClass : DiagGroup<"reinterpret-base-class">;
def Unicode : DiagGroup<"unicode">;
+def UninitializedExplicitInit : DiagGroup<"uninitialized-explicit-init">;
def UninitializedMaybe : DiagGroup<"conditional-uninitialized">;
def UninitializedSometimes : DiagGroup<"sometimes-uninitialized">;
def UninitializedStaticSelfInit : DiagGroup<"static-self-init">;
diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index 8be4f946dce1cc..67c15e7c475943 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -2347,6 +2347,9 @@ def err_init_reference_member_uninitialized : Error<
"reference member of type %0 uninitialized">;
def note_uninit_reference_member : Note<
"uninitialized reference member is here">;
+def warn_field_requires_explicit_init : Warning<
+ "field %select{%1|in %1}0 requires explicit initialization but is not "
+ "explicitly initialized">, InGroup<UninitializedExplicitInit>;
def warn_field_is_uninit : Warning<"field %0 is uninitialized when used here">,
InGroup<Uninitialized>;
def warn_base_class_is_uninit : Warning<
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index 31749e46458d6a..30341b046f95e3 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -5031,6 +5031,7 @@ RecordDecl::RecordDecl(Kind DK, TagKind TK, const ASTContext &C,
setHasNonTrivialToPrimitiveDefaultInitializeCUnion(false);
setHasNonTrivialToPrimitiveDestructCUnion(false);
setHasNonTrivialToPrimitiveCopyCUnion(false);
+ setHasUninitializedExplicitInitFields(false);
setParamDestroyedInCallee(false);
setArgPassingRestrictions(RecordArgPassingKind::CanPassInRegs);
setIsRandomized(false);
@@ -5231,9 +5232,10 @@ unsigned RecordDecl::getODRHash() {
// Only calculate hash on first call of getODRHash per record.
ODRHash Hash;
Hash.AddRecordDecl(this);
- // For RecordDecl the ODRHash is stored in the remaining 26
- // bit of RecordDeclBits, adjust the hash to accomodate.
- setODRHash(Hash.CalculateHash() >> 6);
+ // For RecordDecl the ODRHash is stored in the remaining
+ // bits of RecordDeclBits, adjust the hash to accommodate.
+ static_assert(sizeof(Hash.CalculateHash()) * CHAR_BIT == 32);
+ setODRHash(Hash.CalculateHash() >> (32 - NumOdrHashBits));
return RecordDeclBits.ODRHash;
}
diff --git a/clang/lib/AST/DeclCXX.cpp b/clang/lib/AST/DeclCXX.cpp
index 4163342118c2dc..44f45898fb483d 100644
--- a/clang/lib/AST/DeclCXX.cpp
+++ b/clang/lib/AST/DeclCXX.cpp
@@ -29,6 +29,7 @@
#include "clang/AST/TypeLoc.h"
#include "clang/AST/UnresolvedSet.h"
#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/DiagnosticAST.h"
#include "clang/Basic/IdentifierTable.h"
#include "clang/Basic/LLVM.h"
#include "clang/Basic/LangOptions.h"
@@ -457,6 +458,10 @@ CXXRecordDecl::setBases(CXXBaseSpecifier const * const *Bases,
if (BaseClassDecl->hasMutableFields())
data().HasMutableFields = true;
+ if (BaseClassDecl->hasUninitializedExplicitInitFields() &&
+ BaseClassDecl->isAggregate())
+ setHasUninitializedExplicitInitFields(true);
+
if (BaseClassDecl->hasUninitializedReferenceMember())
data().HasUninitializedReferenceMember = true;
@@ -1113,6 +1118,9 @@ void CXXRecordDecl::addedMember(Decl *D) {
} else if (!T.isCXX98PODType(Context))
data().PlainOldData = false;
+ if (Field->hasAttr<ExplicitInitAttr>())
+ setHasUninitializedExplicitInitFields(true);
+
if (T->isReferenceType()) {
if (!Field->hasInClassInitializer())
data().HasUninitializedReferenceMember = true;
@@ -1372,6 +1380,10 @@ void CXXRecordDecl::addedMember(Decl *D) {
if (!FieldRec->hasCopyAssignmentWithConstParam())
data().ImplicitCopyAssignmentHasConstParam = false;
+ if (FieldRec->hasUninitializedExplicitInitFields() &&
+ FieldRec->isAggregate())
+ setHasUninitializedExplicitInitFields(true);
+
if (FieldRec->hasUninitializedReferenceMember() &&
!Field->hasInClassInitializer())
data().HasUninitializedReferenceMember = true;
@@ -2188,6 +2200,33 @@ void CXXRecordDecl::completeDefinition(CXXFinalOverriderMap *FinalOverriders) {
for (conversion_iterator I = conversion_begin(), E = conversion_end();
I != E; ++I)
I.setAccess((*I)->getAccess());
+
+ ASTContext &Context = getASTContext();
+
+ if (isAggregate() && hasUserDeclaredConstructor() &&
+ !Context.getLangOpts().CPlusPlus20) {
+ // Diagnose any aggregate behavior changes in C++20
+ for (const FieldDecl *FD : fields()) {
+ if (const auto *AT = FD->getAttr<ExplicitInitAttr>())
+ Context.getDiagnostics().Report(
+ AT->getLocation(),
+ diag::warn_cxx20_compat_requires_explicit_init_non_aggregate)
+ << AT << FD << Context.getRecordType(this);
+ }
+ }
+
+ if (!isAggregate() && hasUninitializedExplicitInitFields()) {
+ // Diagnose any fields that required explicit initialization in a
+ // non-aggregate type. (Note that the fields may not be directly in this
+ // type, but in a subobject. In such cases we don't emit diagnoses here.)
+ for (const FieldDecl *FD : fields()) {
+ if (const auto *AT = FD->getAttr<ExplicitInitAttr>())
+ Context.getDiagnostics().Report(AT->getLocation(),
+ diag::warn_attribute_needs_aggregate)
+ << AT << Context.getRecordType(this);
+ }
+ setHasUninitializedExplicitInitFields(false);
+ }
}
bool CXXRecordDecl::mayBeAbstract() const {
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index fd3a5ec49771d9..704cb82b291cc7 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -19232,6 +19232,8 @@ void Sema::ActOnFields(Scope *S, SourceLocation RecLoc, Decl *EnclosingDecl,
if (FT.hasNonTrivialToPrimitiveCopyCUnion() || Record->isUnion())
Record->setHasNonTrivialToPrimitiveCopyCUnion(true);
}
+ if (FD->hasAttr<ExplicitInitAttr>())
+ Record->setHasUninitializedExplicitInitFields(true);
if (FT.isDestructedType()) {
Record->setNonTrivialToPrimitiveDestroy(true);
Record->setParamDestroyedInCallee(true);
diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp
index 0dd5f468cf60bf..b95cbbf4222056 100644
--- a/clang/lib/Sema/SemaInit.cpp
+++ b/clang/lib/Sema/SemaInit.cpp
@@ -264,6 +264,13 @@ static void CheckStringInit(Expr *Str, QualType &DeclT, const ArrayType *AT,
updateStringLiteralType(Str, DeclT);
}
+void emitUninitializedExplicitInitFields(Sema &S, const RecordDecl *R) {
+ for (const FieldDecl *Field : R->fields()) {
+ if (Field->hasAttr<ExplicitInitAttr>())
+ S.Diag(Field->getLocation(), diag::note_entity_declared_at) << Field;
+ }
+}
+
//===----------------------------------------------------------------------===//
// Semantic checking for initializer lists.
//===----------------------------------------------------------------------===//
@@ -738,6 +745,14 @@ void InitListChecker::FillInEmptyInitForField(unsigned Init, FieldDecl *Field,
ILE->updateInit(SemaRef.Context, Init, Filler);
return;
}
+
+ if (!VerifyOnly && Field->hasAttr<ExplicitInitAttr>()) {
+ SemaRef.Diag(ILE->getExprLoc(), diag::warn_field_requires_explicit_init)
+ << /* Var-in-Record */ 0 << Field;
+ SemaRef.Diag(Field->getLocation(), diag::note_entity_declared_at)
+ << Field;
+ }
+
// C++1y [dcl.init.aggr]p7:
// If there are fewer initializer-clauses in the list than there are
// members in the aggregate, then each member not explicitly initialized
@@ -4558,6 +4573,14 @@ static void TryConstructorInitialization(Sema &S,
CXXConstructorDecl *CtorDecl = cast<CXXConstructorDecl>(Best->Function);
if (Result != OR_Deleted) {
+ if (!IsListInit && Kind.getKind() == InitializationKind::IK_Default &&
+ DestRecordDecl != nullptr && DestRecordDecl->isAggregate() &&
+ DestRecordDecl->hasUninitializedExplicitInitFields()) {
+ S.Diag(Kind.getLocation(), diag::warn_field_requires_explicit_init)
+ << /* Var-in-Record */ 1 << DestRecordDecl;
+ emitUninitializedExplicitInitFields(S, DestRecordDecl);
+ }
+
// C++11 [dcl.init]p6:
// If a program calls for the default initialization of an object
// of a const-qualified type T, T shall be a class type with a
@@ -5852,6 +5875,12 @@ static void TryOrBuildParenListInitialization(
} else {
// We've processed all of the args, but there are still members that
// have to be initialized.
+ if (!VerifyOnly && FD->hasAttr<ExplicitInitAttr>()) {
+ S.Diag(Kind.getLocation(), diag::warn_field_requires_explicit_init)
+ << /* Var-in-Record */ 0 << FD;
+ S.Diag(FD->getLocation(), diag::note_entity_declared_at) << FD;
+ }
+
if (FD->hasInClassInitializer()) {
if (!VerifyOnly) {
// C++ [dcl.init]p16.6.2.2
@@ -6457,6 +6486,19 @@ void InitializationSequence::InitializeFrom(Sema &S,
}
}
+ if (!S.getLangOpts().CPlusPlus &&
+ Kind.getKind() == InitializationKind::IK_Default) {
+ RecordDecl *Rec = DestType->getAsRecordDecl();
+ if (Rec && Rec->hasUninitializedExplicitInitFields()) {
+ VarDecl *Var = dyn_cast_or_null<VarDecl>(Entity.getDecl());
+ if (Var && !Initializer) {
+ S.Diag(Var->getLocation(), diag::warn_field_requires_explicit_init)
+ << /* Var-in-Record */ 1 << Rec;
+ emitUninitializedExplicitInitFields(S, Rec);
+ }
+ }
+ }
+
// - If the destination type is a reference type, see 8.5.3.
if (DestType->isReferenceType()) {
// C++0x [dcl.init.ref]p1:
@@ -7310,6 +7352,22 @@ PerformConstructorInitialization(Sema &S,
if (S.DiagnoseUseOfDecl(Step.Function.FoundDecl, Loc))
return ExprError();
+ if (Kind.getKind() == InitializationKind::IK_Value &&
+ Constructor->isImplicit()) {
+ auto *RD = Step.Type.getCanonicalType()->getAsCXXRecordDecl();
+ if (RD && RD->isAggregate() && RD->hasUninitializedExplicitInitFields()) {
+ unsigned I = 0;
+ for (const FieldDecl *FD : RD->fields()) {
+ if (I >= ConstructorArgs.size() && FD->hasAttr<ExplicitInitAttr>()) {
+ S.Diag(Loc, diag::warn_field_requires_explicit_init)
+ << /* Var-in-Record */ 0 << FD;
+ S.Diag(FD->getLocation(), diag::note_entity_declared_at) << FD;
+ }
+ ++I;
+ }
+ }
+ }
+
TypeSourceInfo *TSInfo = Entity.getTypeSourceInfo();
if (!TSInfo)
TSInfo = S.Context.getTrivialTypeSourceInfo(Entity.getType(), Loc);
diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index ee72dd844b59a3..95abd75920c8fe 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -832,6 +832,7 @@ RedeclarableResult ASTDeclReader::VisitRecordDeclImpl(RecordDecl *RD) {
RecordDeclBits.getNextBit());
RD->setHasNonTrivialToPrimitiveDestructCUnion(RecordDeclBits.getNextBit());
RD->setHasNonTrivialToPrimitiveCopyCUnion(RecordDeclBits.getNextBit());
+ RD->setHasUninitializedExplicitInitFields(RecordDeclBits.getNextBit());
RD->setParamDestroyedInCallee(RecordDeclBits.getNextBit());
RD->setArgPassingRestrictions(
(RecordArgPassingKind)RecordDeclBits.getNextBits(/*Width=*/2));
diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index f8ed155ca389d7..3b357f3c50dadb 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -611,6 +611,7 @@ void ASTDeclWriter::VisitRecordDecl(RecordDecl *D) {
RecordDeclBits.addBit(D->hasNonTrivialToPrimitiveDefaultInitializeCUnion());
RecordDeclBits.addBit(D->hasNonTrivialToPrimitiveDestructCUnion());
RecordDeclBits.addBit(D->hasNonTrivialToPrimitiveCopyCUnion());
+ RecordDeclBits.addBit(D->hasUninitializedExplicitInitFields());
RecordDeclBits.addBit(D->isParamDestroyedInCallee());
RecordDeclBits.addBits(llvm::to_underlying(D->getArgPassingRestrictions()), 2);
Record.push_back(RecordDeclBits);
@@ -2480,7 +2481,8 @@ void ASTWriter::WriteDeclAbbrevs() {
// isNonTrivialToPrimitiveCopy, isNonTrivialToPrimitiveDestroy,
// hasNonTrivialToPrimitiveDefaultInitializeCUnion,
// hasNonTrivialToPrimitiveDestructCUnion,
- // hasNonTrivialToPrimitiveCopyCUnion, isParamDestroyedInCallee,
+ // hasNonTrivialToPrimitiveCopyCUnion,
+ // hasUninitializedExplicitInitFields, isParamDestroyedInCallee,
// getArgPassingRestrictions
// ODRHash
Abv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 26));
diff --git a/clang/test/Misc/pragma-attribute-supported-attributes-list.test b/clang/test/Misc/pragma-attribute-supported-attributes-list.test
index 4a6ac39da18ad2..55f196625770ab 100644
--- a/clang/test/Misc/pragma-attribute-supported-attributes-list.test
+++ b/clang/test/Misc/pragma-attribute-supported-attributes-list.test
@@ -79,6 +79,7 @@
// CHECK-NEXT: EnumExtensibility (SubjectMatchRule_enum)
// CHECK-NEXT: Error (SubjectMatchRule_function)
// CHECK-NEXT: ExcludeFromExplicitInstantiation (SubjectMatchRule_variable, SubjectMatchRule_function, SubjectMatchRule_record)
+// CHECK-NEXT: ExplicitInit (SubjectMatchRule_field)
// CHECK-NEXT: ExternalSourceSymbol ((SubjectMatchRule_record, SubjectMatchRule_enum, SubjectMatchRule_enum_constant, SubjectMatchRule_field, SubjectMatchRule_function, SubjectMatchRule_namespace, SubjectMatchRule_objc_category, SubjectMatchRule_objc_implementation, SubjectMatchRule_objc_interface, SubjectMatchRule_objc_method, SubjectMatchRule_objc_property, SubjectMatchRule_objc_protocol, SubjectMatchRule_record, SubjectMatchRule_type_alias, SubjectMatchRule_variable))
// CHECK-NEXT: FlagEnum (SubjectMatchRule_enum)
// CHECK-NEXT: Flatten (SubjectMatchRule_function)
diff --git a/clang/test/Sema/uninit-variables.c b/clang/test/Sema/uninit-variables.c
index 70a00793fd29ed..bad2e14bd28cb8 100644
--- a/clang/test/Sema/uninit-variables.c
+++ b/clang/test/Sema/uninit-variables.c
@@ -551,3 +551,33 @@ struct full_of_empty empty_test_2(void) {
struct full_of_empty e;
return e; // no-warning
}
+
+struct with_explicit_field {
+ int x;
+ int y [[clang::requires_explicit_initialization]]; // #FIELD_Y
+};
+
+struct with_explicit_array {
+ [[clang::requires_explicit_initialization]] int arr[2]; // #FIELD_ARR
+};
+
+struct with_explicit_flex_array {
+ int x;
+ [[clang::requires_explicit_initialization]] int flex_arr[]; // #FIELD_FLEX_ARR
+};
+
+void aggregate() {
+ struct with_explicit_field a; // expected-warning {{field in 'with_explicit_field' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_Y {{'y' declared here}}
+ struct with_explicit_field b = {1}; // expected-warning {{field 'y' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_Y {{'y' declared here}}
+ (void)(&a != &b);
+
+ struct with_explicit_field c = {1, 2};
+ struct with_explicit_field d = {.y = 3};
+ (void)(&c != &d);
+
+ struct with_explicit_array e = {{1}}; // OK -- part of array is still initialized
+ (void)e;
+
+ struct with_explicit_flex_array f = {2}; // expected-warning {{field 'flex_arr' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_FLEX_ARR {{'flex_arr' declared here}}
+ (void)f;
+}
diff --git a/clang/test/SemaCXX/uninitialized.cpp b/clang/test/SemaCXX/uninitialized.cpp
index 8a640c9691b321..95dd488e81a624 100644
--- a/clang/test/SemaCXX/uninitialized.cpp
+++ b/clang/test/SemaCXX/uninitialized.cpp
@@ -1,5 +1,6 @@
-// RUN: %clang_cc1 -fsyntax-only -Wall -Wuninitialized -Wno-unused-value -Wno-unused-lambda-capture -Wno-uninitialized-const-reference -std=c++1z -verify %s
-// RUN: %clang_cc1 -fsyntax-only -Wall -Wuninitialized -Wno-unused-value -Wno-unused-lambda-capture -Wno-uninitialized-const-reference -std=c++1z -verify %s -fexperimental-new-constant-interpreter
+// RUN: %clang_cc1 -fsyntax-only -Wall -Wc++20-compat -Wuninitialized -Wno-unused-value -Wno-unused-lambda-capture -Wno-uninitialized-const-reference -std=c++1z -verify %s
+// RUN: %clang_cc1 -fsyntax-only -Wall -Wc++20-compat -Wuninitialized -Wno-unused-value -Wno-unused-lambda-capture -Wno-uninitialized-const-reference -std=c++1z -verify %s -fexperimental-new-constant-interpreter
+// RUN: %clang_cc1 -fsyntax-only -Wall -Wc++20-compat -Wuninitialized -Wno-unused-value -Wno-unused-lambda-capture -Wno-uninitialized-const-reference -std=c++20 -verify %s
// definitions for std::move
namespace std {
@@ -1472,3 +1473,175 @@ template<typename T> struct Outer {
};
};
Outer<int>::Inner outerinner;
+
+struct Polymorphic { virtual ~Polymorphic() { } };
+
+template<class... Bases>
+struct Inherit : Bases... { // #TYPE_INHERIT
+ int g1; // #FIELD_G1
+};
+
+template<class... Bases>
+struct InheritWithExplicit : Bases... { // #TYPE_INHERIT_WITH_EXPLICIT
+ int g2 [[clang::requires_explicit_initialization]]; // #FIELD_G2
+};
+
+struct Special {};
+
+template<>
+struct Inherit<Special> {
+ int g3 [[clang::requires_explicit_initialization]]; // #FIELD_G3
+};
+
+template<>
+struct InheritWithExplicit<Special> {
+ int g4; // #FIELD_G4
+};
+
+void aggregate() {
+ struct NonAgg {
+ NonAgg() { }
+ [[clang::requires_explicit_initialization]] int na; // expected-warning {{'requires_explicit_initialization' attribute is ignored in non-aggregate type 'NonAgg'}}
+ };
+ NonAgg nonagg; // no-warning
+ (void)nonagg;
+
+ struct S {
+ [[clang::requires_explicit_initialization]] int s1; // #FIELD_S1
+ int s2;
+ int s3 = 12;
+ [[clang::requires_explicit_initialization]] int s4 = 100; // #FIELD_S4
+ static void foo(S) { }
+ };
+
+ struct C {
+#if __cplusplus < 202002L
+ // expected-warning at +1 {{explicit initialization of field 'c1' will not be enforced in C++20 and later because 'C' has a user-declared constructor, making the type no longer an aggregate}}
+ [[clang::requires_explicit_initialization]]
+#endif
+ int c1; // #FIELD_C1
+ C() = default; // Test pre-C++20 aggregates
+ };
+
+ struct D : S { // #TYPE_D
+ int d1;
+ int d2 [[clang::requires_explicit_initialization]]; // #FIELD_D2
+ };
+
+ struct D2 : D { // #TYPE_D2
+ };
+
+ struct E { // #TYPE_E
+ int e1;
+ D e2 [[clang::requires_explicit_initialization]]; // #FIELD_E2
+ struct {
+ [[clang::requires_explicit_initialization]] D e3;
+ D2 e4 [[clang::requires_explicit_initialization]];
+ };
+ };
+
+ S::foo(S{1, 2, 3, 4});
+ S::foo(S{.s1 = 100, .s4 = 100});
+ S::foo(S{.s1 = 100}); // expected-warning {{field 's4' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}}
+
+ S s{.s1 = 100, .s4 = 100};
+ (void)s;
+
+ S t{.s4 = 100}; // expected-warning {{field 's1' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S1 {{'s1' declared here}}
+ (void)t;
+
+ S *ptr1 = new S; // expected-warning {{field in 'S' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}} expected-note@#FIELD_S1 {{'s1' declared here}}
+ delete ptr1;
+
+ S *ptr2 = new S{.s1 = 100, .s4 = 100};
+ delete ptr2;
+
+#if __cplusplus >= 202002L
+ // expected-warning at +3 {{field 's1' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S1 {{'s1' declared here}}
+ // expected-warning at +2 {{field 's4' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}}
+ // expected-warning at +1 {{field 'd2' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_D2 {{'d2' declared here}}
+ D a1({}, 0);
+ (void)a1;
+
+ // expected-warning at +3 {{field 's1' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S1 {{'s1' declared here}}
+ // expected-warning at +2 {{field 's4' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}}
+ // expected-warning at +1 {{field 'd2' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_D2 {{'d2' declared here}}
+ D a2(S{}, 0);
+ (void)a2;
+
+ // expected-warning at +2 {{field 's4' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}}
+ // expected-warning at +1 {{field 'd2' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_D2 {{'d2' declared here}}
+ D a3(S{.s1 = 0}, 0);
+ (void)a3;
+
+ // expected-warning at +3 {{field 's1' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S1 {{'s1' declared here}}
+ // expected-warning at +2 {{field 's4' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}}
+ // expected-warning at +1 {{field 'd2' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_D2 {{'d2' declared here}}
+ D a4(S(), 0);
+ (void)a4;
+
+ // expected-warning at +2 {{field 's4' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}}
+ // expected-warning at +1 {{field 'd2' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_D2 {{'d2' declared here}}
+ D a5(S(0), 0);
+ (void)a5;
+
+ // expected-warning at +2 {{field 's4' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}}
+ // expected-warning at +1 {{field 'd2' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_D2 {{'d2' declared here}}
+ D a6 = {S(0), 0};
+ (void)a6;
+#endif
+
+#if 201103L <= __cplusplus && __cplusplus < 202002L
+ C a; // expected-warning {{field in 'C' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_C1 {{'c1' declared here}}
+ (void)a;
+#endif
+
+ // expected-warning at +2 {{field 's4' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}}
+ // expected-warning at +1 {{field 's1' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S1 {{'s1' declared here}}
+ D b{.d2 = 1};
+ (void)b;
+
+ // expected-warning at +3 {{field 's4' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}}
+ // expected-warning at +2 {{field 'd2' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_D2 {{'d2' declared here}}
+ // expected-warning at +1 {{field 's1' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S1 {{'s1' declared here}}
+ D c{.d1 = 5};
+
+ // expected-warning at +3 {{field 's4' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S4 {{'s4' declared here}}
+ // expected-warning at +2 {{field 'd2' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_D2 {{'d2' declared here}}
+ // expected-warning at +1 {{field 's1' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S1 {{'s1' declared here}}
+ c = {{}, 0};
+ (void)c;
+
+ // expected-note at +3 {{in implicit default constructor for 'D' first required here}}
+ // expected-warning@#TYPE_D {{field in 'S' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_S1 {{'s1' declared here}} expected-note@#FIELD_S4 {{'s4' declared here}}
+ // expected-warning at +1 {{field in 'D' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_D2 {{'d2' declared here}}
+ D d;
+ (void)d;
+
+ // expected-warning at +12 {{field in 'E' requires explicit initialization but is not explicitly initialized}}
+ // expected-note@#FIELD_E2 {{'e2' declared here}}
+ // expected-warning@#TYPE_E {{field in 'D' requires explicit initialization but is not explicitly initialized}}
+ // expected-note at +9 {{in implicit default constructor for 'E' first required here}}
+ // expected-note@#FIELD_D2 {{'d2' declared here}}
+ // expected-warning@#TYPE_E {{field in 'D' requires explicit initialization but is not explicitly initialized}}
+ // expected-note@#FIELD_D2 {{'d2' declared here}}
+ // expected-warning@#TYPE_E {{field in 'D2' requires explicit initialization but is not explicitly initialized}}
+ // expected-note@#TYPE_E {{in implicit default constructor for 'D2' first required here}}
+ // expected-warning@#TYPE_D2 {{field in 'D' requires explicit initialization but is not explicitly initialized}}
+ // expected-note at +2 {{in implicit default constructor for 'E' first required here}}
+ // expected-note@#FIELD_D2 {{'d2' declared here}}
+ E e;
+ (void)e;
+
+ InheritWithExplicit<> agg; // expected-warning {{field in 'InheritWithExplicit<>' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_G2 {{'g2' declared here}}
+ (void)agg;
+
+ InheritWithExplicit<Polymorphic> polymorphic; // expected-warning@#FIELD_G2 {{'requires_explicit_initialization' attribute is ignored in non-aggregate type 'InheritWithExplicit<Polymorphic>'}}
+ (void)polymorphic;
+
+ Inherit<Special> specialized_explicit; // expected-warning {{field in 'Inherit<Special>' requires explicit initialization but is not explicitly initialized}} expected-note@#FIELD_G3 {{'g3' declared here}}
+ (void)specialized_explicit;
+
+ InheritWithExplicit<Special> specialized_implicit; // no-warning
+ (void)specialized_implicit;
+}
More information about the cfe-commits
mailing list