What is the symbol `myLibrary!__scrt_stub_for_is_c_termination_complete+0x12345`

That is a "no idea where it crashed" diagnostic. The +0x12345 offset is far too large. Not uncommon at all, you need good PDBs to get accurate stack traces. Without them it doesn't know anything about the code you wrote and can only go by named DLL entrypoints.

Since the crash appears to be detected in the C runtime library, you might well get lucky by enabling the Microsoft Symbol Server and let it produce the PDB you need. Assuming you opened the minidump in VS, use Tools > Options > Debugging > Symbols to enable the server. General and WinDbg advice is available in this MSDN page.

Is a library name : myLibrary
Is a function name : __scrt_stub_for_is_c_termination_complete
Is a distance from function offset : +0x12345

If you enter the disassembly mode, then you can see a function's address

Also you can see in the (quick)watch to function name, same as disassembly

you can assuming exception raised from specific function and which line.

Watch out : If you debug in Release build , it would be hard to find which code raise the exception. In this case you can compare your assembly between Debug and Release (I cannot explain how it works 'til describing.). Use Debug Build to ease to Debug.

Happy Coding :)