I'm seeing a new failure on the master branch: 883/2538 Test #977: run-boost_histogram-histogram_ostream_ascii_test ......................................***Failed 0.00 sec /home/runner/work/boost/boost/libs/histogram/test/histogram_ostream_ascii_test.cpp(67): test 'str(h).c_str() == expected' ('BEGIN histogram(integer(0, 3, options=underflow | overflow))END' == 'BEGIN histogram(integer(0, 3, options=underflow | overflow)) +------------+ -1 0 | | 0 -1 |=== | 1 3 | ======== | 2 2 | ====== | 3 0 | | +------------+ END') failed in function 'void run_tests() [with Tag = boost::histogram::dynamic_tag]' 1 error detected. Histogram's master hasn't changed for 5 months, so this is probably caused by something else. The CI run is https://github.com/boostorg/boost/actions/runs/19686425029/job/56392904495 and it's being done in response to an Iterator change on master, although the change itself is non-functional.