From: Argyrios Kyrtzidis <akyrtzi@gmail.com>
Date: Fri, 22 Apr 2011 23:57:57 +0000 (+0000)
Subject: Don't allow reinterpret_cast to reference of vector element and property expression... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=bb29d1ba8b0895e3923c724f49845636f35b4bde;p=clang

Don't allow reinterpret_cast to reference of vector element and property expression. Thanks goes to Eli Friedman!

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@130036 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 6e130b1797..910536ab7a 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -2879,8 +2879,8 @@ def err_bad_cxx_cast_member_pointer_size : Error<
   "cannot %select{||reinterpret_cast||C-style cast|}0 from member pointer "
   "type %1 to member pointer type %2 of different size">;
 def err_bad_static_cast_incomplete : Error<"%0 is an incomplete type">;
-def err_bad_reinterpret_cast_bitfield : Error<
-  "reinterpret_cast of a bit-field to %2 needs its address which is not allowed">;
+def err_bad_reinterpret_cast_reference : Error<
+  "reinterpret_cast of a %0 to %1 needs its address which is not allowed">;
 
 // These messages don't adhere to the pattern.
 // FIXME: Display the path somehow better.
diff --git a/lib/Sema/SemaCXXCast.cpp b/lib/Sema/SemaCXXCast.cpp
index 29475539d7..743fdd2566 100644
--- a/lib/Sema/SemaCXXCast.cpp
+++ b/lib/Sema/SemaCXXCast.cpp
@@ -1327,9 +1327,18 @@ static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr,
     //   same effect as the conversion *reinterpret_cast<T*>(&x) with the
     //   built-in & and * operators.
 
-    // Cannot get address of a bitfield.
-    if (SrcExpr.get()->getObjectKind() == OK_BitField) {
-      msg = diag::err_bad_reinterpret_cast_bitfield;
+    const char *inappropriate = 0;
+    switch (SrcExpr.get()->getObjectKind()) {
+    default: break;
+    case OK_BitField:        inappropriate = "bit-field";           break;
+    case OK_VectorComponent: inappropriate = "vector element";      break;
+    case OK_ObjCProperty:    inappropriate = "property expression"; break;
+    }
+    if (inappropriate) {
+      Self.Diag(OpRange.getBegin(), diag::err_bad_reinterpret_cast_reference)
+          << inappropriate << DestType
+          << OpRange << SrcExpr.get()->getSourceRange();
+      msg = 0; SrcExpr = ExprError();
       return TC_NotApplicable;
     }
 
diff --git a/test/SemaCXX/reinterpret-cast.cpp b/test/SemaCXX/reinterpret-cast.cpp
index 2ec45b37cd..f5262496c4 100644
--- a/test/SemaCXX/reinterpret-cast.cpp
+++ b/test/SemaCXX/reinterpret-cast.cpp
@@ -111,5 +111,8 @@ void const_arrays() {
 
 namespace PR9564 {
   struct a { int a : 10; }; a x;
-  int *y = &reinterpret_cast<int&>(x.a); // expected-error {{reinterpret_cast of a bit-field to 'int &' needs its address which is not allowed}}
+  int *y = &reinterpret_cast<int&>(x.a); // expected-error {{not allowed}}
+
+  __attribute((ext_vector_type(4))) typedef float v4;
+  float& w(v4 &a) { return reinterpret_cast<float&>(a[1]); } // expected-error {{not allowed}}
 }