Solving Delphi BPL Package problems where BPLs won't load but you've already recompiled (Windows VirtualStore filesystem issue)

Warren  P picture Warren P · Aug 28, 2012 · Viewed 31.8k times · Source

My general question is how do you troubleshoot "My BPL won't load due to a dependency that just won't go away, no matter how much I clean up and recompile". Update You may think you have a clean recompiled system, but thanks to the inverse-miracle that is Windows and its file system virtualization mis-features, you haven't.

When I try to load my designtime package (in this case named dclFsTee.bpl) into my Delphi IDE (it's the fast report 4 teechart wrapper component package), it complains:

The program can't start because tee7100.bpl is missing from your computer. Try reinstalling ...

That tee7100.bpl is not referenced on any DCP or DCU file on my system THAT I KNOW OF. But clearly, something is wrong, and I can't find the problem.

All Delphi users face a hundred "won't compile or won't load" problems with BPLs. The universal refrain when asked what to do is to clean up your computer.

However, I've now spent hours cleaning up my computer, and while everything compiles file, clearly there must be something out of date hiding somewhere, because the resulting BPL file that I'm trying to load still wants to load a version of a TeeChart BPL that I removed from this system days ago, along with every trace I could find.

The traces of TeeChart stuff in Delphi 2007 that I removed include everything in the $(BDS)\Lib and $(BDS)\Lib\debug folder, and all DCP and BPL folders on the system. Also every TeeChart-unit-named dcu file is gone.

Once you've gotten to the end of the road, what do you try next? (Format the hard drive, buy new computer.) Seriously. I think I'm a smart guy, but I have a 1 tb hard drive, a library path that runs to 80+ folders, and a source code repository that seems to be well organized, but clearly something is hiding where I can't find it.

I have TeeChart Standard 2012, with full source code, and as far as I know, my development machine no longer contains any old TeeChart BPLs or DCP files from the "tee chart tee7100.bpl" version that ships with delphi.

I have run the "recompile.exe" wizard that comes with teechart, which appears to just run MSBuild and build the packages, after writing a {$DEFINE x} declaration to the tee.inc files (there are two of them in the source distribution).

However, somehow, silently it seems like one of the implicit imports into one of the packages is drawing in some stale file which has not been rebuilt, and which therefore tries to load the tee7100.bpl. The new bpl name is tee911.bpl.

Rather than ask the pretty-specific-to-fastreport question, I'm only mentioning it as a specific instance of a general world of hurt that I have faced dozens of times while developing in Delphi.

I'm only giving the fast-report details so you can see that this is in fact a specific instance of a general problem that one faces sometimes inside Delphi IDE when dealing with a component source code or package, or set of packages, with dependencies. Cleaning up your computer so that your code even builds can be tricky.

So here is my Delphi package-to-package-dependency-resolution question:

  1. What is the most effective way to find or trace implicit-load-of-some-no-longer-wanted BPL-problems so that my code (which builds and compiles just fine!) will actually load into the Delphi IDE. The BPL file that results from running Recompile seems to be linking properly to the right DCP files, and no old/stale DCP or DCU files are present. The new DCP file name is tee911.dcp, for instance.

  2. Can you get somehow, any idea of what package is actually stale, and what is being read and linked and imported statically when the .bpl links? (I'm thinking maybe like a special MAP-like file for BPL files?)

Update After many hours of fighting with this, and using every trick I know, I realized I hadn't checked for some VirtualStore related issues caused by file virtualization in Windows 7. That means that Windows 7 lies to the programs that run on top of it. It gives you another version of the file, that isn't the one you want. This can be deadly in several ways; One; You recompile a BPL but that's not the one that loads. The BPL that was killing me was in the SysWow64 folder that was part of the VirtualStore. Note that the virtualstore basically makes phantom files appear that are only there if you're a certain "low privelege" program, which Delphi 2007 on Win7/64 bit, apparently is. To remove BPL files in your SysWow64 VIRTUALSTORE folder for your current user account:

   del %HOMEPATH%\AppData\Local\VirtualStore\Windows\SysWow64\*.bpl

... Some days I just hate Windows architecture. Anyways, I'm not going to put the above as the answer, because I'd like to know if anyone has a better way or any tip or suggestion that might help next time.

Answer

Warren  P picture Warren P · Jan 22, 2013

Okay nobody else answered so I'll put this here to be helpful for future people:

-- Remember Windows VirtualStore when cleaning up broken systems which have old versions of DLLs on them including TeeChart, FastReport, Indy and so on which tend to be involved in messes because they can exist both as "out of box packages that ship with delphi" as well as frequently installed as upgraded versions if you purchased and installed them from the vendors directly, or third, you may have your own compiled copy in your company's mega-component-pack-directory.

-- When searching for duplicate or out of date BPLs, doing a file search in windows doesn't look in the virtualstores, you'll have to locate and zap the whole virtualstore area for your process or user, or program, manually.

The second level of this issue is this:

The dependency graph for FastReports is complex:

  • It depends on Indy and you might have your own version of Indy, and Delphi itself has one, and other things on your hard drive might have their own copy of Indy.

  • It supports various editions of TeeChart, including the binaries that come with Delphi, and perhaps the Standard version or other purchased version of TeeChart that you might have bought from Steema.

  • It uses a precompiled header include file to do the compilation and not just ONE but TWO different copies of an identically named include (.inc) file.

  • When you use their own compiler tool (recompile FastReport) it works pretty reliably but isn't the best for when you want to build everything in your project from a single build script, thus the source of my problem.

  • The key is to learn everything there is to know about the dependencies of all the components in your giant pile of packages, and to organize your system cleanly so that you don't have old stuff (like Indy and TeeChart bpls, dcp, or dcu files) lying around. Cleaning that up is quite a complex job if you don't know what you're doing.

    • A utility to really remove all traces of the version of Indy and TeeChart that ship with your system, and the "Embarcadero edition" of FastReports is key to getting this situation resolved. A general tip is that "if a version of X ships with Delphi and you are going to install a new version, prepare to suffer until your system is really cleaned up".

    • A really amazing technique to avoid all this crap is to just not install Indy, FastReport or TeeChart (uncheck them or skip them) during your initial Delphi IDE install, then install them yourself, one by one, from sources. Just because a version comes pre-installed in Delphi doesn't make that a good thing. (Update: You can no longer unselect Indy during install, it's part of the base Delphi product since at least Delphi XE8. A clean-up utility to remove the built-in Indy from Delphi's own lib dirs is necessary for anyone who builds their own.)

    • Another really amazing technique is to run the Installers for commercial components on a virtual machine, then just collect up the pascal source code and transfer that onto your clean development machine, and build it yourself. That way you can avoid the terrible things that happen when you've got BPLs and stuff scattered around your system, and even installed into C:\Windows\System32 (on 32 bit systems) and C:\Windows\SysWow64 (the equivalent path on 64 bit systems).