https://bugs.winehq.org/show_bug.cgi?id=36509
--- Comment #4 from Austin English austinenglish@gmail.com --- (In reply to Vincent Povirk from comment #3)
There's nothing in test_createDebugger that calls into Mono. The unknown frames must be in mscoree.
Fair; looks like a valgrind thing, since debug symbols should be there:
austin@laptop:~/wine-valgrind/dlls/mscoree$ file *so mscoree.dll.so: ELF 32-bit LSB pie executable, Intel 80386, version 1 (SYSV), dynamically linked, with debug_info, not stripped