From: Eli Friedman <eli.friedman@gmail.com>
Date: Tue, 17 Jan 2012 02:13:45 +0000 (+0000)
Subject: Revert r148271; this requires more thought.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=55693fbe18e9431dbb0ea9e20d140d8bc6bc4c72;p=clang

Revert r148271; this requires more thought.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@148276 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index f8e58267cc..049074d6e5 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -4318,10 +4318,6 @@ def err_cannot_pass_objc_interface_to_vararg : Error<
   "cannot pass object with interface type %0 by-value through variadic "
   "%select{function|block|method}1">;
 
-def err_cannot_pass_non_pod_to_vararg_ppe : Error<
-  "passing object of type %0 to variadic call in a context "
-  "which is potentially evaluatable, but not obviously "
-  "potentially evaluatable, is not yet implemented">;
 def warn_cannot_pass_non_pod_arg_to_vararg : Warning<
   "cannot pass object of %select{non-POD|non-trivial}0 type %1 through variadic"
   " %select{function|block|method|constructor}2; call will abort at runtime">,
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 33102ccc04..1655c9105f 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -486,34 +486,17 @@ ExprResult Sema::DefaultArgumentPromotion(Expr *E) {
   //     has a class type, the conversion copy-initializes a temporary
   //     of type T from the glvalue and the result of the conversion
   //     is a prvalue for the temporary.
-  // This requirement has some strange effects for
-  // PotentiallyPotentiallyEvaluated contexts; specifically, doing precisely
-  // what the standard requires involves mutating the AST once we decide
-  // whether an expression is potentially evaluated. Rather than actually try and
-  // model this correctly, we just make sure to handle the important cases:
-  // for types with a trivial copy constructor/destructor, we build the AST
-  // as if it were potentially evaluated, and we give an error in other cases
-  // if the context turns out to be potentially evaluatable.
-  // FIXME: If anyone actually cares about this case, try to implement
-  // it correctly, or at least improve the diagnostic output a bit.
-  if (getLangOptions().CPlusPlus && E->isGLValue()) {
-    if (ExprEvalContexts.back().Context == PotentiallyPotentiallyEvaluated &&
-        E->getType()->isRecordType() &&
-        (!E->getType().isTriviallyCopyableType(Context) ||
-         E->getType().isDestructedType())) {
-      ExprEvalContexts.back()
-          .addDiagnostic(E->getExprLoc(),
-              PDiag(diag::err_cannot_pass_non_pod_to_vararg_ppe)
-                  << E->getType());
-    } else if (ExprEvalContexts.back().Context != Unevaluated) {
-      ExprResult Temp = PerformCopyInitialization(
-                         InitializedEntity::InitializeTemporary(E->getType()),
-                                                  E->getExprLoc(),
-                                                  Owned(E));
-      if (Temp.isInvalid())
-        return ExprError();
-      E = Temp.get();
-    }
+  // FIXME: add some way to gate this entire thing for correctness in
+  // potentially potentially evaluated contexts.
+  if (getLangOptions().CPlusPlus && E->isGLValue() && 
+      ExprEvalContexts.back().Context != Unevaluated) {
+    ExprResult Temp = PerformCopyInitialization(
+                       InitializedEntity::InitializeTemporary(E->getType()),
+                                                E->getExprLoc(),
+                                                Owned(E));
+    if (Temp.isInvalid())
+      return ExprError();
+    E = Temp.get();
   }
 
   return Owned(E);
diff --git a/test/SemaCXX/vararg-non-pod.cpp b/test/SemaCXX/vararg-non-pod.cpp
index aaf6cc1191..42c27fb30e 100644
--- a/test/SemaCXX/vararg-non-pod.cpp
+++ b/test/SemaCXX/vararg-non-pod.cpp
@@ -88,8 +88,7 @@ Base &get_base(...);
 int eat_base(...);
 
 void test_typeid(Base &base) {
-  (void)typeid(get_base(base)); // expected-warning{{cannot pass object of non-POD type 'Base' through variadic function; call will abort at runtime}} \
-                                // expected-error {{potentially evaluatable, but not obviously potentially evaluatable}}
+  (void)typeid(get_base(base)); // expected-warning{{cannot pass object of non-POD type 'Base' through variadic function; call will abort at runtime}}
   (void)typeid(eat_base(base)); // okay
 }