[cfe-commits] r44486 - /cfe/trunk/AST/Expr.cpp

[Chris Lattner]

Author: lattner
Date: Sat Dec  1 00:07:34 2007
New Revision: 44486

URL: http://llvm.org/viewvc/llvm-project?rev=44486&view=rev
Log:
make the unused expression warning less noisy by not warning about comma exprs whose
LHS and RHS both have side effects.

Modified:
    cfe/trunk/AST/Expr.cpp

Modified: cfe/trunk/AST/Expr.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/AST/Expr.cpp?rev=44486&r1=44485&r2=44486&view=diff

==============================================================================
--- cfe/trunk/AST/Expr.cpp (original)
+++ cfe/trunk/AST/Expr.cpp Sat Dec  1 00:07:34 2007
@@ -243,8 +243,15 @@
       return UO->getSubExpr()->hasLocalSideEffect();
     }
   }
-  case BinaryOperatorClass:
-    return cast<BinaryOperator>(this)->isAssignmentOp();
+  case BinaryOperatorClass: {
+    const BinaryOperator *BinOp = cast<BinaryOperator>(this);
+    // Consider comma to have side effects if the LHS and RHS both do.
+    if (BinOp->getOpcode() == BinaryOperator::Comma)
+      return BinOp->getLHS()->hasLocalSideEffect() &&
+             BinOp->getRHS()->hasLocalSideEffect();
+      
+    return BinOp->isAssignmentOp();
+  }
   case CompoundAssignOperatorClass:
     return true;