unexpected behaviour with boost range join on rvalue

[Matei David <matei@…>]

I'm trying to append one element to a range, and iterate over the resulting compound range. When the rhs of the join is an lvalue, everything seems ok. However, when the rhs of the join is an rvalue, I'm seeing something unexpected.

Specifically, when such a joined range is accessed directly by a for(auto e : range) loop, or when it is saved in a variable using auto, then iterated over, the singleton in the second container is not produced correctly. If however the joined range is passed by reference (other than non-const lvalue, obviously), then iterated over, the result is correct.

[Matei David <matei@…>]

I'm using gcc-4.8.2 and clang-3.5. I'm compiling with:

[g++|clang++] -std=c++11 -Wall -Wextra -pedantic example-join.cpp -o example-join

The results I'm seeing are either "12 34", which is ok, or "12 0", which is not ok. Note that the last element is not even default constructed (which would be 99, not 0).