[cfe-commits] r80674 - /cfe/trunk/include/clang/AST/Decl.h

[Douglas Gregor]

Author: dgregor
Date: Tue Sep  1 11:13:00 2009
New Revision: 80674

URL: http://llvm.org/viewvc/llvm-project?rev=80674&view=rev
Log:
Tip-toe around strict-aliasing violation. Fixes PR4061.

Modified:
    cfe/trunk/include/clang/AST/Decl.h

Modified: cfe/trunk/include/clang/AST/Decl.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/Decl.h?rev=80674&r1=80673&r2=80674&view=diff

==============================================================================
--- cfe/trunk/include/clang/AST/Decl.h (original)
+++ cfe/trunk/include/clang/AST/Decl.h Tue Sep  1 11:13:00 2009
@@ -290,11 +290,13 @@
   /// default argument.
   struct UninstantiatedDefaultArgument;
 
+  typedef llvm::PointerUnion4<Stmt *, EvaluatedStmt *, 
+                              UnparsedDefaultArgument *, 
+                              UninstantiatedDefaultArgument *> InitType;
+  
   /// \brief The initializer for this variable or, for a ParmVarDecl, the 
   /// C++ default argument.
-  mutable llvm::PointerUnion4<Stmt *, EvaluatedStmt *, 
-                              UnparsedDefaultArgument *, 
-                              UninstantiatedDefaultArgument *> Init;
+  mutable InitType Init;
   
 private:
   // FIXME: This can be packed into the bitfields in Decl.
@@ -368,7 +370,15 @@
   Stmt **getInitAddress() {
     if (EvaluatedStmt *ES = Init.dyn_cast<EvaluatedStmt*>())
       return &ES->Value;
-    return reinterpret_cast<Stmt **>(&Init); // FIXME: ugly hack
+    
+    // This union hack tip-toes around strict-aliasing rules.
+    union {
+      InitType *InitPtr;
+      Stmt **StmtPtr;
+    };
+    
+    InitPtr = &Init;
+    return StmtPtr;
   }
 
   void setInit(ASTContext &C, Expr *I);