[Attributor] Make unimplemented method pure virtual.

Otherwise the compiler mistakes it for a vtable anchor.

llvm-svn: 371298

diff --git a/llvm/include/llvm/Transforms/IPO/Attributor.h b/llvm/include/llvm/Transforms/IPO/Attributor.h
index 4e98465..84aab8f 100644 (file)
--- a/llvm/include/llvm/Transforms/IPO/Attributor.h
+++ b/llvm/include/llvm/Transforms/IPO/Attributor.h
@@ -1713,9 +1713,9 @@ struct AAValueSimplify : public StateWrapper<BooleanState, AbstractAttribute>,
   ///}
 
   /// Return an assumed simplified value if a single candidate is found. If
-  /// there cannot be one, return original value. If it is not clear yet, return the
-  /// Optional::NoneType.
-  virtual Optional<Value *> getAssumedSimplifiedValue(Attributor &A) const;
+  /// there cannot be one, return original value. If it is not clear yet, return
+  /// the Optional::NoneType.
+  virtual Optional<Value *> getAssumedSimplifiedValue(Attributor &A) const = 0;
 
   /// Create an abstract attribute view for the position \p IRP.
   static AAValueSimplify &createForPosition(const IRPosition &IRP,