[clang] 3925fbc - nullptr returned from ActOnTag() is not a valid result
Aaron Ballman via cfe-commits
cfe-commits at lists.llvm.org
Tue Jan 17 13:04:46 PST 2023
Author: Aaron Ballman
Date: 2023-01-17T16:04:35-05:00
New Revision: 3925fbc80019f72bf3f5174736f348acfb5768b0
URL: https://github.com/llvm/llvm-project/commit/3925fbc80019f72bf3f5174736f348acfb5768b0
DIFF: https://github.com/llvm/llvm-project/commit/3925fbc80019f72bf3f5174736f348acfb5768b0.diff
LOG: nullptr returned from ActOnTag() is not a valid result
DeclResult tracks two states: valid/invalid and usable/unusable.
Passing a null pointer to the constructor creates a valid but unusable
result and we wanted an invalid result instead. This changes some
functions to return a DeclResult rather than a Decl * to make it harder
to get this incorrect in callers.
Discovered when working on https://reviews.llvm.org/D141280.
Co-authored-by: Haojian Wu <hokein at google.com>
Co-authored-by: Aaron Ballman <aaron at aaronballman.com>
Differential Revision: https://reviews.llvm.org/D141580
Added:
Modified:
clang/include/clang/Sema/Sema.h
clang/lib/Parse/ParseDecl.cpp
clang/lib/Sema/SemaDecl.cpp
clang/lib/Sema/SemaDeclCXX.cpp
clang/lib/Sema/SemaTemplate.cpp
clang/test/Parser/cxx-undeclared-identifier.cpp
clang/test/Parser/recovery.cpp
clang/test/SemaCXX/invalid-template-params.cpp
clang/test/SemaCXX/rdar42746401.cpp
Removed:
################################################################################
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index 35e319879a98d..7a95989ee6d44 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -3314,22 +3314,24 @@ class Sema final {
OOK_Macro,
};
- Decl *ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
- SourceLocation KWLoc, CXXScopeSpec &SS, IdentifierInfo *Name,
- SourceLocation NameLoc, const ParsedAttributesView &Attr,
- AccessSpecifier AS, SourceLocation ModulePrivateLoc,
- MultiTemplateParamsArg TemplateParameterLists, bool &OwnedDecl,
- bool &IsDependent, SourceLocation ScopedEnumKWLoc,
- bool ScopedEnumUsesClassTag, TypeResult UnderlyingType,
- bool IsTypeSpecifier, bool IsTemplateParamOrArg,
- OffsetOfKind OOK, SkipBodyInfo *SkipBody = nullptr);
-
- Decl *ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
- unsigned TagSpec, SourceLocation TagLoc,
- CXXScopeSpec &SS, IdentifierInfo *Name,
- SourceLocation NameLoc,
- const ParsedAttributesView &Attr,
- MultiTemplateParamsArg TempParamLists);
+ DeclResult ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
+ SourceLocation KWLoc, CXXScopeSpec &SS,
+ IdentifierInfo *Name, SourceLocation NameLoc,
+ const ParsedAttributesView &Attr, AccessSpecifier AS,
+ SourceLocation ModulePrivateLoc,
+ MultiTemplateParamsArg TemplateParameterLists,
+ bool &OwnedDecl, bool &IsDependent,
+ SourceLocation ScopedEnumKWLoc,
+ bool ScopedEnumUsesClassTag, TypeResult UnderlyingType,
+ bool IsTypeSpecifier, bool IsTemplateParamOrArg,
+ OffsetOfKind OOK, SkipBodyInfo *SkipBody = nullptr);
+
+ DeclResult ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
+ unsigned TagSpec, SourceLocation TagLoc,
+ CXXScopeSpec &SS, IdentifierInfo *Name,
+ SourceLocation NameLoc,
+ const ParsedAttributesView &Attr,
+ MultiTemplateParamsArg TempParamLists);
TypeResult ActOnDependentTag(Scope *S,
unsigned TagSpec,
diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index 75937c0d6a952..4a26f0443634c 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -4972,7 +4972,7 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
DSC == DeclSpecContext::DSC_type_specifier,
DSC == DeclSpecContext::DSC_template_param ||
DSC == DeclSpecContext::DSC_template_type_arg,
- OffsetOfState, &SkipBody);
+ OffsetOfState, &SkipBody).get();
if (SkipBody.ShouldSkip) {
assert(TUK == Sema::TUK_Definition && "can only skip a definition");
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 0fd68c55cc172..1de4caee01bed 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -16583,17 +16583,16 @@ static bool isAcceptableTagRedeclContext(Sema &S, DeclContext *OldDC,
///
/// \param SkipBody If non-null, will be set to indicate if the caller should
/// skip the definition of this tag and treat it as if it were a declaration.
-Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
- SourceLocation KWLoc, CXXScopeSpec &SS,
- IdentifierInfo *Name, SourceLocation NameLoc,
- const ParsedAttributesView &Attrs, AccessSpecifier AS,
- SourceLocation ModulePrivateLoc,
- MultiTemplateParamsArg TemplateParameterLists,
- bool &OwnedDecl, bool &IsDependent,
- SourceLocation ScopedEnumKWLoc,
- bool ScopedEnumUsesClassTag, TypeResult UnderlyingType,
- bool IsTypeSpecifier, bool IsTemplateParamOrArg,
- OffsetOfKind OOK, SkipBodyInfo *SkipBody) {
+DeclResult
+Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, SourceLocation KWLoc,
+ CXXScopeSpec &SS, IdentifierInfo *Name, SourceLocation NameLoc,
+ const ParsedAttributesView &Attrs, AccessSpecifier AS,
+ SourceLocation ModulePrivateLoc,
+ MultiTemplateParamsArg TemplateParameterLists, bool &OwnedDecl,
+ bool &IsDependent, SourceLocation ScopedEnumKWLoc,
+ bool ScopedEnumUsesClassTag, TypeResult UnderlyingType,
+ bool IsTypeSpecifier, bool IsTemplateParamOrArg,
+ OffsetOfKind OOK, SkipBodyInfo *SkipBody) {
// If this is not a definition, it must have a name.
IdentifierInfo *OrigName = Name;
assert((Name != nullptr || TUK == TUK_Definition) &&
@@ -16619,7 +16618,7 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
TUK == TUK_Friend, isMemberSpecialization, Invalid)) {
if (Kind == TTK_Enum) {
Diag(KWLoc, diag::err_enum_template);
- return nullptr;
+ return true;
}
if (TemplateParams->size() > 0) {
@@ -16627,7 +16626,7 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
// be a member of another template).
if (Invalid)
- return nullptr;
+ return true;
OwnedDecl = false;
DeclResult Result = CheckClassTemplate(
@@ -16646,7 +16645,7 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
if (!TemplateParameterLists.empty() && isMemberSpecialization &&
CheckTemplateDeclScope(S, TemplateParameterLists.back()))
- return nullptr;
+ return true;
}
// Figure out the underlying type if this a enum declaration. We need to do
@@ -16762,26 +16761,26 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
DC = computeDeclContext(SS, false);
if (!DC) {
IsDependent = true;
- return nullptr;
+ return true;
}
} else {
DC = computeDeclContext(SS, true);
if (!DC) {
Diag(SS.getRange().getBegin(), diag::err_dependent_nested_name_spec)
<< SS.getRange();
- return nullptr;
+ return true;
}
}
if (RequireCompleteDeclContext(SS, DC))
- return nullptr;
+ return true;
SearchDC = DC;
// Look-up name inside 'foo::'.
LookupQualifiedName(Previous, DC);
if (Previous.isAmbiguous())
- return nullptr;
+ return true;
if (Previous.empty()) {
// Name lookup did not find anything. However, if the
@@ -16793,7 +16792,7 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
if (Previous.wasNotFoundInCurrentInstantiation() &&
(TUK == TUK_Reference || TUK == TUK_Friend)) {
IsDependent = true;
- return nullptr;
+ return true;
}
// A tag 'foo::bar' must already exist.
@@ -16810,7 +16809,7 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
// -- every member of class T that is itself a type
if (TUK != TUK_Reference && TUK != TUK_Friend &&
DiagnoseClassNameShadow(SearchDC, DeclarationNameInfo(Name, NameLoc)))
- return nullptr;
+ return true;
// If this is a named struct, check to see if there was a previous forward
// declaration or definition.
@@ -16874,7 +16873,7 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
// Note: there used to be some attempt at recovery here.
if (Previous.isAmbiguous())
- return nullptr;
+ return true;
if (!getLangOpts().CPlusPlus && TUK != TUK_Reference) {
// FIXME: This makes sure that we ignore the contexts associated
@@ -17531,7 +17530,7 @@ Decl *Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
if (New->isBeingDefined())
if (auto RD = dyn_cast<RecordDecl>(New))
RD->completeDefinition();
- return nullptr;
+ return true;
} else if (SkipBody && SkipBody->ShouldSkip) {
return SkipBody->Previous;
} else {
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index cf1242beffe99..c8d384c643b3d 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -16922,12 +16922,10 @@ FriendDecl *Sema::CheckFriendTypeDecl(SourceLocation LocStart,
/// Handle a friend tag declaration where the scope specifier was
/// templated.
-Decl *Sema::ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
- unsigned TagSpec, SourceLocation TagLoc,
- CXXScopeSpec &SS, IdentifierInfo *Name,
- SourceLocation NameLoc,
- const ParsedAttributesView &Attr,
- MultiTemplateParamsArg TempParamLists) {
+DeclResult Sema::ActOnTemplatedFriendTag(
+ Scope *S, SourceLocation FriendLoc, unsigned TagSpec, SourceLocation TagLoc,
+ CXXScopeSpec &SS, IdentifierInfo *Name, SourceLocation NameLoc,
+ const ParsedAttributesView &Attr, MultiTemplateParamsArg TempParamLists) {
TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
bool IsMemberSpecialization = false;
@@ -16940,7 +16938,7 @@ Decl *Sema::ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
if (TemplateParams->size() > 0) {
// This is a declaration of a class template.
if (Invalid)
- return nullptr;
+ return true;
return CheckClassTemplate(S, TagSpec, TUK_Friend, TagLoc, SS, Name,
NameLoc, Attr, TemplateParams, AS_public,
@@ -16955,7 +16953,7 @@ Decl *Sema::ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
}
}
- if (Invalid) return nullptr;
+ if (Invalid) return true;
bool isAllExplicitSpecializations = true;
for (unsigned I = TempParamLists.size(); I-- > 0; ) {
@@ -16991,7 +16989,7 @@ Decl *Sema::ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
QualType T = CheckTypenameType(Keyword, TagLoc, QualifierLoc,
*Name, NameLoc);
if (T.isNull())
- return nullptr;
+ return true;
TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
if (isa<DependentNameType>(T)) {
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 1b30116192616..da74267cc65d2 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -10186,7 +10186,7 @@ Sema::ActOnExplicitInstantiation(Scope *S, SourceLocation ExternLoc,
/*ModulePrivateLoc=*/SourceLocation(), MultiTemplateParamsArg(), Owned,
IsDependent, SourceLocation(), false, TypeResult(),
/*IsTypeSpecifier*/ false,
- /*IsTemplateParamOrArg=*/false, /*OOK=*/OOK_Outside);
+ /*IsTemplateParamOrArg=*/false, /*OOK=*/OOK_Outside).get();
assert(!IsDependent && "explicit instantiation of dependent name not yet handled");
if (!TagD)
diff --git a/clang/test/Parser/cxx-undeclared-identifier.cpp b/clang/test/Parser/cxx-undeclared-identifier.cpp
index c5bf8ae9944ee..4751dadd1c498 100644
--- a/clang/test/Parser/cxx-undeclared-identifier.cpp
+++ b/clang/test/Parser/cxx-undeclared-identifier.cpp
@@ -15,5 +15,5 @@ namespace ImplicitInt {
// PR7180
int f(a::b::c); // expected-error {{use of undeclared identifier 'a'}}
-class Foo::Bar { // expected-error {{use of undeclared identifier 'Foo'}} \
- // expected-error {{expected ';' after class}}
+class Foo::Bar { // expected-error {{use of undeclared identifier 'Foo'}}
+ // expected-error {{expected unqualified-id}}
diff --git a/clang/test/Parser/recovery.cpp b/clang/test/Parser/recovery.cpp
index 5a20f98d32912..4e2811c4cac92 100644
--- a/clang/test/Parser/recovery.cpp
+++ b/clang/test/Parser/recovery.cpp
@@ -212,6 +212,6 @@ struct ::, struct ::; // expected-error 2 {{expected identifier}} expected-error
enum ::, enum ::; // expected-error 2 {{expected identifier}}
struct ::__super, struct ::__super; // expected-error 2 {{expected identifier}} expected-error 2 {{expected '::' after '__super'}}
struct ::template foo, struct ::template bar; // expected-error 2 {{expected identifier}} expected-error 2 {{declaration of anonymous struct must be a definition}} expected-warning {{declaration does not declare anything}}
-struct ::foo struct::; // expected-error {{no struct named 'foo' in the global namespace}} expected-error {{expected identifier}} expected-error {{declaration of anonymous struct must be a definition}}
+struct ::foo struct::; // expected-error {{no struct named 'foo' in the global namespace}} expected-error {{expected identifier}}
class :: : {} a; // expected-error {{expected identifier}} expected-error {{expected class name}}
}
diff --git a/clang/test/SemaCXX/invalid-template-params.cpp b/clang/test/SemaCXX/invalid-template-params.cpp
index 6f19aa9d5ddbe..4eb8edc0141fe 100644
--- a/clang/test/SemaCXX/invalid-template-params.cpp
+++ b/clang/test/SemaCXX/invalid-template-params.cpp
@@ -15,9 +15,8 @@ class C0 {
public:
template<typename T0, typename T1 = T0 // missing closing angle bracket
struct S0 {}; // expected-error {{'S0' cannot be defined in a type specifier}}
- // expected-error at -1 {{cannot combine with previous 'type-name' declaration specifier}}
- // expected-error at -2 {{expected ',' or '>' in template-parameter-list}}
- // expected-error at -3 {{declaration does not declare anything}}
+ // expected-error at -1 {{expected ',' or '>' in template-parameter-list}}
+ // expected-error at -2 {{declaration does not declare anything}}
C0() : m(new S0<int>) {} // expected-error {{expected '(' for function-style cast or type construction}}
// expected-error at -1 {{expected expression}}
S0<int> *m; // expected-error {{expected member name or ';' after declaration specifiers}}
diff --git a/clang/test/SemaCXX/rdar42746401.cpp b/clang/test/SemaCXX/rdar42746401.cpp
index ff9dff456ce47..a2a941f2ae836 100644
--- a/clang/test/SemaCXX/rdar42746401.cpp
+++ b/clang/test/SemaCXX/rdar42746401.cpp
@@ -4,4 +4,4 @@ template <int>
class b;
class c; // expected-note{{forward declaration}}
-::b<0> struct c::d // expected-error{{incomplete type}} expected-error{{cannot combine}} expected-error{{expected unqualified-id}}
+::b<0> struct c::d // expected-error{{incomplete type}} expected-error{{expected unqualified-id}}
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