Add context note to diagnostics that occur while declaring an implicit special member function.
llvm-svn: 296020
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index cc50e6c..c31ec7d 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -10164,19 +10164,34 @@
bool WasAlreadyBeingDeclared;
DeclaringSpecialMember(Sema &S, CXXRecordDecl *RD, Sema::CXXSpecialMember CSM)
- : S(S), D(RD, CSM), SavedContext(S, RD) {
+ : S(S), D(RD, CSM), SavedContext(S, RD) {
WasAlreadyBeingDeclared = !S.SpecialMembersBeingDeclared.insert(D).second;
if (WasAlreadyBeingDeclared)
// This almost never happens, but if it does, ensure that our cache
// doesn't contain a stale result.
S.SpecialMemberCache.clear();
-
- // FIXME: Register a note to be produced if we encounter an error while
- // declaring the special member.
+ else {
+ // Register a note to be produced if we encounter an error while
+ // declaring the special member.
+ Sema::CodeSynthesisContext Ctx;
+ Ctx.Kind = Sema::CodeSynthesisContext::DeclaringSpecialMember;
+ // FIXME: We don't have a location to use here. Using the class's
+ // location maintains the fiction that we declare all special members
+ // with the class, but (1) it's not clear that lying about that helps our
+ // users understand what's going on, and (2) there may be outer contexts
+ // on the stack (some of which are relevant) and printing them exposes
+ // our lies.
+ Ctx.PointOfInstantiation = RD->getLocation();
+ Ctx.Entity = RD;
+ Ctx.SpecialMember = CSM;
+ S.pushCodeSynthesisContext(Ctx);
+ }
}
~DeclaringSpecialMember() {
- if (!WasAlreadyBeingDeclared)
+ if (!WasAlreadyBeingDeclared) {
S.SpecialMembersBeingDeclared.erase(D);
+ S.popCodeSynthesisContext();
+ }
}
/// \brief Are we already trying to declare this special member?
diff --git a/clang/lib/Sema/SemaTemplateInstantiate.cpp b/clang/lib/Sema/SemaTemplateInstantiate.cpp
index 7b09b77..314dfe3 100644
--- a/clang/lib/Sema/SemaTemplateInstantiate.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiate.cpp
@@ -196,6 +196,7 @@
return true;
case DefaultTemplateArgumentChecking:
+ case DeclaringSpecialMember:
return false;
}
@@ -207,8 +208,7 @@
SourceLocation PointOfInstantiation, SourceRange InstantiationRange,
Decl *Entity, NamedDecl *Template, ArrayRef<TemplateArgument> TemplateArgs,
sema::TemplateDeductionInfo *DeductionInfo)
- : SemaRef(SemaRef), SavedInNonInstantiationSFINAEContext(
- SemaRef.InNonInstantiationSFINAEContext) {
+ : SemaRef(SemaRef) {
// Don't allow further instantiation if a fatal error and an uncompilable
// error have occurred. Any diagnostics we might have raised will not be
// visible, and we do not need to construct a correct AST.
@@ -228,14 +228,12 @@
Inst.NumTemplateArgs = TemplateArgs.size();
Inst.DeductionInfo = DeductionInfo;
Inst.InstantiationRange = InstantiationRange;
+ SemaRef.pushCodeSynthesisContext(Inst);
+
AlreadyInstantiating =
!SemaRef.InstantiatingSpecializations
.insert(std::make_pair(Inst.Entity->getCanonicalDecl(), Inst.Kind))
.second;
- SemaRef.InNonInstantiationSFINAEContext = false;
- SemaRef.CodeSynthesisContexts.push_back(Inst);
- if (!Inst.isInstantiationRecord())
- ++SemaRef.NonInstantiationEntries;
}
}
@@ -348,38 +346,55 @@
PointOfInstantiation, InstantiationRange, Param, Template,
TemplateArgs) {}
+void Sema::pushCodeSynthesisContext(CodeSynthesisContext Ctx) {
+ Ctx.SavedInNonInstantiationSFINAEContext = InNonInstantiationSFINAEContext;
+ InNonInstantiationSFINAEContext = false;
+
+ CodeSynthesisContexts.push_back(Ctx);
+
+ if (!Ctx.isInstantiationRecord())
+ ++NonInstantiationEntries;
+}
+
+void Sema::popCodeSynthesisContext() {
+ auto &Active = CodeSynthesisContexts.back();
+ if (!Active.isInstantiationRecord()) {
+ assert(NonInstantiationEntries > 0);
+ --NonInstantiationEntries;
+ }
+
+ InNonInstantiationSFINAEContext = Active.SavedInNonInstantiationSFINAEContext;
+
+ // Name lookup no longer looks in this template's defining module.
+ assert(CodeSynthesisContexts.size() >=
+ CodeSynthesisContextLookupModules.size() &&
+ "forgot to remove a lookup module for a template instantiation");
+ if (CodeSynthesisContexts.size() ==
+ CodeSynthesisContextLookupModules.size()) {
+ if (Module *M = CodeSynthesisContextLookupModules.back())
+ LookupModulesCache.erase(M);
+ CodeSynthesisContextLookupModules.pop_back();
+ }
+
+ // If we've left the code synthesis context for the current context stack,
+ // stop remembering that we've emitted that stack.
+ if (CodeSynthesisContexts.size() ==
+ LastEmittedCodeSynthesisContextDepth)
+ LastEmittedCodeSynthesisContextDepth = 0;
+
+ CodeSynthesisContexts.pop_back();
+}
+
void Sema::InstantiatingTemplate::Clear() {
if (!Invalid) {
- auto &Active = SemaRef.CodeSynthesisContexts.back();
- if (!Active.isInstantiationRecord()) {
- assert(SemaRef.NonInstantiationEntries > 0);
- --SemaRef.NonInstantiationEntries;
- }
- SemaRef.InNonInstantiationSFINAEContext
- = SavedInNonInstantiationSFINAEContext;
-
- // Name lookup no longer looks in this template's defining module.
- assert(SemaRef.CodeSynthesisContexts.size() >=
- SemaRef.CodeSynthesisContextLookupModules.size() &&
- "forgot to remove a lookup module for a template instantiation");
- if (SemaRef.CodeSynthesisContexts.size() ==
- SemaRef.CodeSynthesisContextLookupModules.size()) {
- if (Module *M = SemaRef.CodeSynthesisContextLookupModules.back())
- SemaRef.LookupModulesCache.erase(M);
- SemaRef.CodeSynthesisContextLookupModules.pop_back();
- }
-
- // If we've left the code synthesis context for the current context stack,
- // stop remembering that we've emitted that stack.
- if (SemaRef.CodeSynthesisContexts.size() ==
- SemaRef.LastEmittedCodeSynthesisContextDepth)
- SemaRef.LastEmittedCodeSynthesisContextDepth = 0;
-
- if (!AlreadyInstantiating)
+ if (!AlreadyInstantiating) {
+ auto &Active = SemaRef.CodeSynthesisContexts.back();
SemaRef.InstantiatingSpecializations.erase(
std::make_pair(Active.Entity, Active.Kind));
+ }
- SemaRef.CodeSynthesisContexts.pop_back();
+ SemaRef.popCodeSynthesisContext();
+
Invalid = true;
}
}
@@ -603,6 +618,12 @@
<< cast<FunctionDecl>(Active->Entity)
<< Active->InstantiationRange;
break;
+
+ case CodeSynthesisContext::DeclaringSpecialMember:
+ Diags.Report(Active->PointOfInstantiation,
+ diag::note_in_declaration_of_implicit_special_member)
+ << cast<CXXRecordDecl>(Active->Entity) << Active->SpecialMember;
+ break;
}
}
}
@@ -617,7 +638,7 @@
Active != ActiveEnd;
++Active)
{
- switch(Active->Kind) {
+ switch (Active->Kind) {
case CodeSynthesisContext::TemplateInstantiation:
// An instantiation of an alias template may or may not be a SFINAE
// context, depending on what else is on the stack.
@@ -643,7 +664,17 @@
// or deduced template arguments, so SFINAE applies.
assert(Active->DeductionInfo && "Missing deduction info pointer");
return Active->DeductionInfo;
+
+ case CodeSynthesisContext::DeclaringSpecialMember:
+ // This happens in a context unrelated to template instantiation, so
+ // there is no SFINAE.
+ return None;
}
+
+ // The inner context was transparent for SFINAE. If it occurred within a
+ // non-instantiation SFINAE context, then SFINAE applies.
+ if (Active->SavedInNonInstantiationSFINAEContext)
+ return Optional<TemplateDeductionInfo *>(nullptr);
}
return None;