Read debugging information at runtime from an application-Collection of common programming errors

What are the common formats/types of debugging symbols?

DWARF and STABS (those are embedded inside executable, in special sections), Program Database (PDB; external file, used by MSVC).

How do they relate to compilers and platforms? Is it always the same format on GCC and MinGW among platforms?

GCC uses DWARF/STABS (I think it’s a GCC compile-time option) both on Linux (ELF) and Windows (PE), don’t know about others. MSVC always uses PDB.

Can I check in runtime whether the build has them and what format are they in?

You can parse the executable image and see if there are sections with debugging info (see STABS documentation and DWARF specs). PDB files are distributed either with executables or via symbol servers (so if you don’t want to go online, check if there is X.pdb for X.exe/X.dll).

About how to read and use those symbols – I don’t know about DWARF/STABS (there’s probably something around GNU binutils that can locate and extract those), but for PDB your best bet is to use dbghelp – its usage is pretty well documented and there are a lot of examples available on the net. There’s also DIA SDK that can be used to query PDB files.

Are the debugging symbols standardised well enough that I can expect some degree of portability for such solutions?

DWARF has a formal specification, and it’s complicated as hell. PDB AFAIK is not documented, but dbghelp/DIA are, and are the recommended way.