[cfe-commits] [PATCH] C++11 nullptr-convert standalone tool

[Edwin Vane]

  So I tried looking for ImplicitCastExpr where the CastKind was CK_NullToPointer or CK_NullToMemberPointer. This does handle most of the cases with a single simple matcher. However, there are two test of my test cases failing:

  int *p;
  p = static_cast<T*>(reinterpret_cast<int*>((void*)NULL));
  // CHECK: p = nullptr;

  template <typename T>
  struct Bar {
    Bar(T *p = NULL) : m_p(p) {
    // CHECK: Bar(T *p = nullptr) : m_p(p) {

  In the first case, the NULL gets replaced but the explicit casts do not. This is expected given the simple matcher. I expect the fix here is to match all cast expressions and use Expr::isNullPointerConstant().

  The second case doesn't work because there's no implicit cast involved. Looking at the AST dump I see this:

  template <typename T = int> struct Bar {
      struct Bar;
      Bar(int *p) : m_p((ImplicitCastExpr 0x428fad8 <basic.cpp:67:26> 'int *' <LValueToRValue>
    (DeclRefExpr 0x428fa80 <col:26> 'int *' lvalue ParmVar 0x428e880 'p' 'int *'))

  and

  template <typename T> struct Bar {
      struct Bar;
      Bar<T>(T *p = (IntegerLiteral 0x428c550 <basic.cpp:7:14> 'int' 0)
  ) : m_p((DeclRefExpr 0x428c598 <basic.cpp:67:26> 'T *' lvalue ParmVar 0x4284e00 'p' 'T *')

  It seems to me that in this template case, there should be an implicit cast since we know T* will be some sort of pointer type. Is that a bug or something I just have to live with?

http://llvm-reviews.chandlerc.com/D136