Reduce the number of move constructions when constructing a std::function.  This fixes http://llvm.org/bugs/show_bug.cgi?id=12105.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@151652 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed