Delphi – Loading BDE BPL from another directory

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-- When searching for duplicate or out of date BPLs, doing a file search in windows doesn't look in the virtualstores, you'll have to locate and zap the whole virtualstore area for your process or user, or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