Fix compile time regression and memory leak

Author: usx95

clang/include/clang/Basic/Attr.td

@@ -1896,17 +1896,17 @@ def LifetimeCaptureBy : DeclOrTypeAttr {
   let Documentation = [LifetimeCaptureByDocs];
   let AdditionalMembers = [{
 private:
-  SmallVector<IdentifierInfo*, 1> ArgIdents;
-  SmallVector<SourceLocation, 1> ArgLocs;
+  SmallVector<IdentifierInfo*> ArgIdents;
+  SmallVector<SourceLocation> ArgLocs;
 
 public:
   static constexpr int THIS = 0;
   static constexpr int INVALID = -1;
   static constexpr int UNKNOWN = -2;
   static constexpr int GLOBAL = -3;
 
-  void setArgs(SmallVector<IdentifierInfo*>&& Idents,
-               SmallVector<SourceLocation>&& Locs) { 
+  void setArgs(SmallVector<IdentifierInfo*> Idents,
+               SmallVector<SourceLocation> Locs) { 
     assert(Idents.size() == Locs.size());
     assert(Idents.size() == params_Size);
     ArgIdents = std::move(Idents);

clang/lib/Sema/SemaDeclAttr.cpp

@@ -3876,8 +3876,8 @@ LifetimeCaptureByAttr *Sema::ParseLifetimeCaptureByAttr(const ParsedAttr &AL,
         << AL.getRange();
     return nullptr;
   }
-  SmallVector<IdentifierInfo *, 1> ParamIdents;
-  SmallVector<SourceLocation, 1> ParamLocs;
+  SmallVector<IdentifierInfo *> ParamIdents;
+  SmallVector<SourceLocation> ParamLocs;
   for (unsigned I = 0; I < AL.getNumArgs(); ++I) {
     if (AL.isArgExpr(I)) {
       Expr *E = AL.getArgAsExpr(I);
@@ -3894,15 +3894,15 @@ LifetimeCaptureByAttr *Sema::ParseLifetimeCaptureByAttr(const ParsedAttr &AL,
     ParamIdents.push_back(IdLoc->Ident);
     ParamLocs.push_back(IdLoc->Loc);
   }
-  SmallVector<int, 1> FakeParamIndices(ParamIdents.size(),
-                                       LifetimeCaptureByAttr::INVALID);
+  SmallVector<int> FakeParamIndices(ParamIdents.size(),
+                                    LifetimeCaptureByAttr::INVALID);
   LifetimeCaptureByAttr *CapturedBy = ::new (Context) LifetimeCaptureByAttr(
       Context, AL, FakeParamIndices.data(), FakeParamIndices.size());
   CapturedBy->setArgs(std::move(ParamIdents), std::move(ParamLocs));
   return CapturedBy;
 }
 
-static void HandleLifetimeCaptureByAttr(Sema &S, Decl *D,
+static void handleLifetimeCaptureByAttr(Sema &S, Decl *D,
                                         const ParsedAttr &AL) {
   // Do not allow multiple attributes.
   if (D->hasAttr<LifetimeCaptureByAttr>()) {
@@ -3919,7 +3919,24 @@ static void HandleLifetimeCaptureByAttr(Sema &S, Decl *D,
 
 void Sema::LazyProcessLifetimeCaptureByParams(FunctionDecl *FD) {
   bool HasImplicitThisParam = isInstanceMethod(FD);
-
+  SmallVector<LifetimeCaptureByAttr *, 1> Attrs;
+  for (ParmVarDecl *PVD : FD->parameters())
+    if (auto *A = PVD->getAttr<LifetimeCaptureByAttr>())
+      Attrs.push_back(A);
+  if (HasImplicitThisParam) {
+    TypeSourceInfo *TSI = FD->getTypeSourceInfo();
+    if (!TSI)
+      return;
+    AttributedTypeLoc ATL;
+    for (TypeLoc TL = TSI->getTypeLoc();
+         (ATL = TL.getAsAdjusted<AttributedTypeLoc>());
+         TL = ATL.getModifiedLoc()) {
+      if (auto *A = ATL.getAttrAs<LifetimeCaptureByAttr>())
+        Attrs.push_back(const_cast<LifetimeCaptureByAttr *>(A));
+    }
+  }
+  if (Attrs.empty())
+    return;
   llvm::StringMap<int> NameIdxMapping;
   NameIdxMapping["global"] = LifetimeCaptureByAttr::GLOBAL;
   NameIdxMapping["unknown"] = LifetimeCaptureByAttr::UNKNOWN;
@@ -3936,9 +3953,7 @@ void Sema::LazyProcessLifetimeCaptureByParams(FunctionDecl *FD) {
         Diag(PVD->getLocation(), diag::err_capture_by_param_uses_reserved_name)
             << (PVD->getName() == "unknown");
   };
-  auto HandleCaptureBy = [&](LifetimeCaptureByAttr *CapturedBy) {
-    if (!CapturedBy)
-      return;
+  for (auto *CapturedBy : Attrs) {
     const auto &Entities = CapturedBy->getArgIdents();
     for (size_t I = 0; I < Entities.size(); ++I) {
       StringRef Name = Entities[I]->getName();
@@ -3956,22 +3971,6 @@ void Sema::LazyProcessLifetimeCaptureByParams(FunctionDecl *FD) {
         DisallowReservedParams(Name);
       CapturedBy->setParamIdx(I, It->second);
     }
-  };
-  for (ParmVarDecl *PVD : FD->parameters())
-    HandleCaptureBy(PVD->getAttr<LifetimeCaptureByAttr>());
-  if (!HasImplicitThisParam)
-    return;
-  TypeSourceInfo *TSI = FD->getTypeSourceInfo();
-  if (!TSI)
-    return;
-  AttributedTypeLoc ATL;
-  for (TypeLoc TL = TSI->getTypeLoc();
-       (ATL = TL.getAsAdjusted<AttributedTypeLoc>());
-       TL = ATL.getModifiedLoc()) {
-    auto *A = ATL.getAttrAs<LifetimeCaptureByAttr>();
-    if (!A)
-      continue;
-    HandleCaptureBy(const_cast<LifetimeCaptureByAttr *>(A));
   }
 }
 
@@ -6753,7 +6752,7 @@ ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D, const ParsedAttr &AL,
     handleCallbackAttr(S, D, AL);
     break;
   case ParsedAttr::AT_LifetimeCaptureBy:
-    HandleLifetimeCaptureByAttr(S, D, AL);
+    handleLifetimeCaptureByAttr(S, D, AL);
     break;
   case ParsedAttr::AT_CalledOnce:
     handleCalledOnceAttr(S, D, AL);