[llvm-commits] [llvm] r112106 - /llvm/trunk/include/llvm/ADT/SmallVector.h

[John McCall]

Author: rjmccall
Date: Wed Aug 25 18:11:24 2010
New Revision: 112106

URL: http://llvm.org/viewvc/llvm-project?rev=112106&view=rev
Log:
Provide an explicit specialization of SmallVector at N=0 which does
not require its type argument to be complete if no members are
actually used.


Modified:
    llvm/trunk/include/llvm/ADT/SmallVector.h

Modified: llvm/trunk/include/llvm/ADT/SmallVector.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ADT/SmallVector.h?rev=112106&r1=112105&r2=112106&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ADT/SmallVector.h (original)
+++ llvm/trunk/include/llvm/ADT/SmallVector.h Wed Aug 25 18:11:24 2010
@@ -707,6 +707,39 @@
 
 };
 
+/// Specialize SmallVector at N=0.  This specialization guarantees
+/// that it can be instantiated at an incomplete T if none of its
+/// members are required.
+template <typename T>
+class SmallVector<T,0> : public SmallVectorImpl<T> {
+public:
+  SmallVector() : SmallVectorImpl<T>(0) {
+  }
+
+  explicit SmallVector(unsigned Size, const T &Value = T())
+    : SmallVectorImpl<T>(0) {
+    this->reserve(Size);
+    while (Size--)
+      this->push_back(Value);
+  }
+
+  template<typename ItTy>
+  SmallVector(ItTy S, ItTy E) : SmallVectorImpl<T>(0) {
+    this->append(S, E);
+  }
+
+  SmallVector(const SmallVector &RHS) : SmallVectorImpl<T>(0) {
+    if (!RHS.empty())
+      SmallVectorImpl<T>::operator=(RHS);
+  }
+
+  const SmallVector &operator=(const SmallVector &RHS) {
+    SmallVectorImpl<T>::operator=(RHS);
+    return *this;
+  }
+
+};
+
 } // End llvm namespace
 
 namespace std {