Is it possible to regenerate symbols for an exe?

Question

One of my co-workers shipped a hot fix build to a customer, and subsequently deleted the pdb file. The build in question is crashing (intermittently) and we have a couple of crash dumps. We have all the source code in version control, and can compile it to an equivalent .exe and get symbols for that one. However, those symbols don't match the crash dump exactly. It seems like several of the functions are off by some constant offset, but we've only looked at a handful.

I'd love to be able to do the following (I can fake parts of this manually, but it's a huge amount of work): get a stack trace for each thread in the dump and cast pointers in the dump to the appropriate type and have them show up in the Visual Studio debugger. I'm using 2005, if that matters.

Is there a tool to let us recreate a pdb given the source code, all the .obj files, and the original .exe? Or is there a setting when we compile/link to say "make it exactly like this other exe you just did" or something like that?

Quick update, based on answers so far: I have the exe file that we sent to the customer, just not the pdb that corresponds to it, if that helps. I'd just as soon not send them a new build (if possible), because it takes about a week of running to get the crash dumps, and the customer is already at the "why isn't this already fixed?" stage. (If we do send another build, I'd prefer it to be one that either fixes the problem or has additional debugging in the area of interest, not just the same code.) I know it's possible to do some of this manually with a lot of guesswork; that's what we're currently doing. But it's a pain, so I'm hoping there's a way to automate it.

Answer 1

When you have the sources, it's quite easy to find the correspondence between them and the exe file. Just ask them to send you the exe file along with the crash log and use IDA.

What you are asking is much more difficult than that, considering also that you need it for "one use only".

Answer 2

If your build system enables you to recreate any binary from any revision you have in your history, then you should be able to get the build ID from the customer, and regenerate that same exact build ID, along with all the binaries and so forth. That will take a while if you have a large project, of course, but it will also yield the debugging file that you need.

If you have no way to perform an exact reproduction of a build, then look at this situation, think hard about some others that might crop up, and start moving to make it possible to regenerate all successful builds and associated files in the project's history. This will make it much easier to be able to work problems like this in the future.

Answer 3

You cannot recreate a PDB to match a pre-existing executable. The PDB contains a "finger print" that is unique for each compilation. Unless you can make the old PDB magically reappear, you should whack your cow-orker in the back of the head (Gibbs-style, if you watch NCIS), recompile the whole thing, store the PDB somewhere safe, and ship a new executable to your customer, and let the crashes come.