[llvm-commits] CVS: llvm/include/Support/DenseMap.h

[Chris Lattner]

On Wed, 25 Feb 2004, Alkis Evlogimenos wrote:
> > Fix a bug in the densemap that was killing the local allocator, and probably
> > other clients.  The problem is that the nullVal member was left to the default
> > constructor to initialize, which for int's does nothing (ie, leaves it unspecified).
> >
> > To get a zero value, we must use T().  It's C++ wonderful? :)
>
> Wow... I always thought that all members had T() called if you didn't
> specify it.

Nope.  Strange but true:

   T v;
and
   T v = T();

act differently when T is an int, pointer or other primitive type.  I
personally think that this is foolish, as even a dumb compiler can
eliminate default dead initializations of primitives, but the C++ commitee
didn't ask me. :)

-Chris

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