PR24164, PR39336: init-captures are not distinct full-expressions.

Rather, they are subexpressions of the enclosing lambda-expression, and
any temporaries in them are destroyed at the end of that
full-expression, or when the corresponding lambda-expression is
destroyed if they are lifetime-extended.

llvm-svn: 344801

1 files changed, 10 insertions, 27 deletions

diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp
index dd5dfaacf24..eb1dd8975d1 100644
--- a/clang/lib/Sema/SemaExprCXX.cpp
+++ b/clang/lib/Sema/SemaExprCXX.cpp
@@ -7764,41 +7764,24 @@ Sema::CorrectDelayedTyposInExpr(Expr *E, VarDecl *InitDecl,
 
 ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC,
                                      bool DiscardedValue,
-                                     bool IsConstexpr,
-                                     bool IsLambdaInitCaptureInitializer) {
+                                     bool IsConstexpr) {
   ExprResult FullExpr = FE;
 
   if (!FullExpr.get())
     return ExprError();
 
-  // If we are an init-expression in a lambdas init-capture, we should not
-  // diagnose an unexpanded pack now (will be diagnosed once lambda-expr
-  // containing full-expression is done).
-  // template<class ... Ts> void test(Ts ... t) {
-  //   test([&a(t)]() { <-- (t) is an init-expr that shouldn't be diagnosed now.
-  //     return a;
-  //   }() ...);
-  // }
-  // FIXME: This is a hack. It would be better if we pushed the lambda scope
-  // when we parse the lambda introducer, and teach capturing (but not
-  // unexpanded pack detection) to walk over LambdaScopeInfos which don't have a
-  // corresponding class yet (that is, have LambdaScopeInfo either represent a
-  // lambda where we've entered the introducer but not the body, or represent a
-  // lambda where we've entered the body, depending on where the
-  // parser/instantiation has got to).
-  if (!IsLambdaInitCaptureInitializer &&
-      DiagnoseUnexpandedParameterPack(FullExpr.get()))
+  if (DiagnoseUnexpandedParameterPack(FullExpr.get()))
     return ExprError();
 
-  // Top-level expressions default to 'id' when we're in a debugger.
-  if (DiscardedValue && getLangOpts().DebuggerCastResultToId &&
-      FullExpr.get()->getType() == Context.UnknownAnyTy) {
-    FullExpr = forceUnknownAnyToType(FullExpr.get(), Context.getObjCIdType());
-    if (FullExpr.isInvalid())
-      return ExprError();
-  }
-
   if (DiscardedValue) {
+    // Top-level expressions default to 'id' when we're in a debugger.
+    if (getLangOpts().DebuggerCastResultToId &&
+        FullExpr.get()->getType() == Context.UnknownAnyTy) {
+      FullExpr = forceUnknownAnyToType(FullExpr.get(), Context.getObjCIdType());
+      if (FullExpr.isInvalid())
+        return ExprError();
+    }
+
     FullExpr = CheckPlaceholderExpr(FullExpr.get());
     if (FullExpr.isInvalid())
       return ExprError();