I'm using gcc-8.2 on an x86_64 ubuntu-18.04 machine.
Sorry I can't narrow it down more than that.
I hope that's enough to repro.
$ cat tests/test-suite.log
=============================================
libunwind 1.4-rc1: tests/test-suite.log
=============================================
# TOTAL: 37
# PASS: 36
# SKIP: 0
# XFAIL: 0
# FAIL: 1
# XPASS: 0
# ERROR: 0
.. contents:: :depth: 2
FAIL: run-coredump-unwind-mdi
=============================
Segmentation fault (core dumped)
FAILURE: procedure names are missing/incorrect
FAIL run-coredump-unwind-mdi (exit status: 255)