We've got this large application written in Delphi 5, and development is ongoing to this day. There is research going on into migrating to newer versions, but so far there is no success, as some 3rd party components have not been updated in ages and do not work on later versions.

In the meantime however people need to continue work on it. Now Delphi 5 IDE is no real treat. It's pretty bug-ridden and lacks a lot of features of contemporary IDEs which makes it difficult to use. Especially when it comes to debugging.

So I was wondering - would it be possible to use Visual Studio in the process? As far as I know the .PDB file format is pretty old and is well documented. Could it be possible to make the Delphi compiler to somehow generate a .PDB files for it's compiled results? Then the program could be debugged with Visual Studio, possibly to a much greater extent than in the original IDE.

Well, the absolute Holy Grail would be to move all development to VS, just keeping the compiler from Delphi, but I imagine that would be pretty impossible.