[PATCH] D21109: IR: Call dropAllReferences from GlobalVariable's destructor.

[Peter Collingbourne via llvm-commits]

pcc added a comment.

It's only a problem for classes that need to override `dropAllReferences`. Most classes are fine with the `User::~User` behaviour, which just clears operands using `User::dropAllReferences`.


http://reviews.llvm.org/D21109