Split RequireCompleteType into a function that actually requires that the type

is complete (with an error produced if not) and a function that merely queries
whether the type is complete. Either way we'll trigger instantiation if
necessary, but only the former will diagnose and recover from missing module
imports.

The intent of this change is to prevent a class of bugs where code would call
RequireCompleteType(..., 0) and then ignore the result. With modules, we must
check the return value and use it to determine whether the definition of the
type is visible.

This also fixes a debug info quality issue: calls to isCompleteType do not
trigger the emission of debug information for a type in limited-debug-info
mode. This allows us to avoid emitting debug information for type definitions
in more cases where we believe it is safe to do so.

llvm-svn: 256049

1 files changed, 13 insertions, 12 deletions

diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index 58949bfd440..62f4f18bd3a 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -1822,7 +1822,7 @@ bool Sema::IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType) {
 
     // We have already pre-calculated the promotion type, so this is trivial.
     if (ToType->isIntegerType() &&
-        !RequireCompleteType(From->getLocStart(), FromType, 0))
+        isCompleteType(From->getLocStart(), FromType))
       return Context.hasSameUnqualifiedType(
           ToType, FromEnumType->getDecl()->getPromotionType());
   }
@@ -3085,7 +3085,7 @@ IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
          S.IsDerivedFrom(From->getLocStart(), From->getType(), ToType)))
       ConstructorsOnly = true;
 
-    if (S.RequireCompleteType(From->getExprLoc(), ToType, 0)) {
+    if (!S.isCompleteType(From->getExprLoc(), ToType)) {
       // We're not going to find any constructors.
     } else if (CXXRecordDecl *ToRecordDecl
                  = dyn_cast<CXXRecordDecl>(ToRecordType->getDecl())) {
@@ -3159,7 +3159,7 @@ IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType,
 
   // Enumerate conversion functions, if we're allowed to.
   if (ConstructorsOnly || isa<InitListExpr>(From)) {
-  } else if (S.RequireCompleteType(From->getLocStart(), From->getType(), 0)) {
+  } else if (!S.isCompleteType(From->getLocStart(), From->getType())) {
     // No conversion functions from incomplete types.
   } else if (const RecordType *FromRecordType
                                    = From->getType()->getAs<RecordType>()) {
@@ -4047,7 +4047,7 @@ Sema::CompareReferenceRelationship(SourceLocation Loc,
   ObjCLifetimeConversion = false;
   if (UnqualT1 == UnqualT2) {
     // Nothing to do.
-  } else if (!RequireCompleteType(Loc, OrigT2, 0) &&
+  } else if (isCompleteType(Loc, OrigT2) &&
              isTypeValid(UnqualT1) && isTypeValid(UnqualT2) &&
              IsDerivedFrom(Loc, UnqualT2, UnqualT1))
     DerivedToBase = true;
@@ -4314,7 +4314,7 @@ TryReferenceInit(Sema &S, Expr *Init, QualType DeclType,
     //          conversion functions (13.3.1.6) and choosing the best
     //          one through overload resolution (13.3)),
     if (!SuppressUserConversions && T2->isRecordType() &&
-        !S.RequireCompleteType(DeclLoc, T2, 0) &&
+        S.isCompleteType(DeclLoc, T2) &&
         RefRelationship == Sema::Ref_Incompatible) {
       if (FindConversionForRefInit(S, ICS, DeclType, DeclLoc,
                                    Init, T2, /*AllowRvalues=*/false,
@@ -4377,7 +4377,7 @@ TryReferenceInit(Sema &S, Expr *Init, QualType DeclType,
   //          in the second case (or, in either case, to an appropriate base
   //          class subobject).
   if (!SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible &&
-      T2->isRecordType() && !S.RequireCompleteType(DeclLoc, T2, 0) &&
+      T2->isRecordType() && S.isCompleteType(DeclLoc, T2) &&
       FindConversionForRefInit(S, ICS, DeclType, DeclLoc,
                                Init, T2, /*AllowRvalues=*/true,
                                AllowExplicit)) {
@@ -4515,7 +4515,7 @@ TryListConversion(Sema &S, InitListExpr *From, QualType ToType,
 
   // We need a complete type for what follows. Incomplete types can never be
   // initialized from init lists.
-  if (S.RequireCompleteType(From->getLocStart(), ToType, 0))
+  if (!S.isCompleteType(From->getLocStart(), ToType))
     return Result;
 
   // Per DR1467:
@@ -5449,14 +5449,15 @@ ExprResult Sema::PerformContextualImplicitConversion(
     Expr *From;
 
     TypeDiagnoserPartialDiag(ContextualImplicitConverter &Converter, Expr *From)
-        : TypeDiagnoser(Converter.Suppress), Converter(Converter), From(From) {}
+        : Converter(Converter), From(From) {}
 
     void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
       Converter.diagnoseIncomplete(S, Loc, T) << From->getSourceRange();
     }
   } IncompleteDiagnoser(Converter, From);
 
-  if (RequireCompleteType(Loc, T, IncompleteDiagnoser))
+  if (Converter.Suppress ? !isCompleteType(Loc, T)
+                         : RequireCompleteType(Loc, T, IncompleteDiagnoser))
     return From;
 
   // Look for a conversion to an integral or enumeration type.
@@ -6432,7 +6433,7 @@ Sema::AddConversionCandidate(CXXConversionDecl *Conversion,
                                 &ConversionRef, VK_RValue);
 
   QualType ConversionType = Conversion->getConversionType();
-  if (RequireCompleteType(From->getLocStart(), ConversionType, 0)) {
+  if (!isCompleteType(From->getLocStart(), ConversionType)) {
     Candidate.Viable = false;
     Candidate.FailureKind = ovl_fail_bad_final_conversion;
     return;
@@ -6681,7 +6682,7 @@ void Sema::AddMemberOperatorCandidates(OverloadedOperatorKind Op,
   //        the set of member candidates is empty.
   if (const RecordType *T1Rec = T1->getAs<RecordType>()) {
     // Complete the type if it can be completed.
-    if (RequireCompleteType(OpLoc, T1, 0) && !T1Rec->isBeingDefined())
+    if (!isCompleteType(OpLoc, T1) && !T1Rec->isBeingDefined())
       return;
     // If the type is neither complete nor being defined, bail out now.
     if (!T1Rec->getDecl()->getDefinition())
@@ -7031,7 +7032,7 @@ BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty,
     HasNullPtrType = true;
   } else if (AllowUserConversions && TyRec) {
     // No conversion functions in incomplete types.
-    if (SemaRef.RequireCompleteType(Loc, Ty, 0))
+    if (!SemaRef.isCompleteType(Loc, Ty))
       return;
 
     CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl());