I started out on a project using Lazarus/Fpc 32 bit (2.0.0/3.0.4) and now I want to switch to the 64 bit version of Lazarus/Fpc. I have installed both 32 and 64 bit versions using the downloadable installers so they are separate programs in their separate folder trees.

I thought that I could start Lazarus 64 bit and then open the 32 bit project and save it as a 64 bit project afterwards, but that failed completely...
Turns out I have to also install some dependencies that the project uses. Most important is the PasLibVlc library...

Since Lazarus can compile across platforms, can it also be directed to compile on the *same* platform (Windows) but using different bit versions (32 bit and 64 bit)?

Since I have both installed on my laptop it would be nice to be able to manage both 32 and 64 bit versions from the same environment, if possible.

But how should I go about telling my Lazarus 32 bit about the 64 bit compiler already installed (it is the same version)?

And how do I differentiate between the different target executables when building? Can Lazarus be told to build both at the same time?

Bo Berglund wrote

Since I have both installed on my laptop it would be nice to be able to manage both 32 and 64 bit versions from the same environment, if possible.

I found the following method:

Build modes can be used to handle this.

I have enabled build modes Win32 and Win64 and set these to different executable output names. I also modified the target OS and CPU family correspondingly.

Still it is a manual operation to select the correct build mode depending on which IDE I have opened.
Is there some way to automatically select build mode depending on the version of the IDE (32 or 64 bit on Windows)?

In the 64 bit IDE I can now build both 32 and 64 bit executables just by switching the build mode.

But if I use Lazarus 32 bit then it it works fine to build the 32 bit version but complains when I try to build the 64 bit version:

"Compiler:
C:\Programs\lazarus_2.0\fpc\3.0.4\bin\i386-...\fpc.exe does not support target x86_64-win64"

It seems like the 64 bit fpc compiler can handle both targets but the 32 bit one not....

Is this solvable?

OTH, if the 64 bit Lazarus can handle both 32 and 64 bit Windows, why bother with the 32 bit Lazarus?

This is easy to do that, you only need one Lazarus, the 64bit version and the cross-i386 fpc compiler, you can remove Lazarus 32. The only point to be careful is the default target for a new project will be Win64 and you have to add a Win32 build mode to all your projects. But the default target is saved with the project so this is a one time setup. And to not overlap 32 and 64 build files you must be sure the Output directory path contain $(TargetCPU).

The files to install are lazarus-2.0.2-fpc-3.0.4-win64 first, then lazarus-2.0.2-fpc-3.0.4-cross-i386-win32-win64, both available from https://sourceforge.net/projects/lazarus/files/Lazarus%20Windows%2064%20bits/Lazarus%202.0.2/

Patrick

Thanks for the description!

Right now I have the following installed in my Win7 x64 environment: Lazarus 1.6
Lazarus 1.8
Lazarus 1.8.4 32 bit
Lazarus 2.0.0 32 bit
Lazarus 2.0.0 64 bit

All of these have internbal fpc directories containing the correspondiing fpc compiler files.

Do you recommend uninstalling ALL of these and instead get and install Lazarus 2.0.2 as described above?

What happens with the project history of the removed versions? Is there some file I can save to keep that available?

I don't know your workflow and why you keep the old version of Lazarus? for maintenance of older version of your applications?

In this case do not remove them but install the 2.0.2 Lazarus and cross-compiler in a new Lazarus 2.0.2 directory then create a new config for 2.0.2 as usual.

Patrick

Patrick Chevalley wrote

I don't know your workflow and why you keep the old version of Lazarus? for maintenance of older version of your applications?

Not really, I tend to instal the latest version now and then and so I build up a library of older versions, which I don't use anymore... So I will remove them shortly, but first install 2.0.2 as you suggested.

In this case do not remove them but install the 2.0.2 Lazarus and cross-compiler in a new Lazarus 2.0.2 directory then create a new config for 2.0.2 as usual.

Is there a cross-compiler which allows building the programs for Linux too (Linux running on the same CPU)?
Maybe also for Linux on ARM (Raspberry Pi)?

Currently I install Lazarus/FPC on the linux machines and then I use Subversion to get the sources over to Linux and build there. It would be more convenient to be able to build the tools in my main environment and use on Linux by moving the binary over.

The same with me (plus some more, in particular trunk installations for Lazarus and fpc). This is indispensable for testing when your code should not be tied to the newest IDE version.

Normally, it is no problem to switch between different versions. But be aware: When loading an project in a new version may change the project in a way that it is not readable by the old version again. Laz 2.0, for example, can add the line "Application.Scaled" to the project unit when you use the High-dpi features - this is a problem for 1.6. (You may enclose the line by an $IFDEF which helps for some time, but after some changes the IDE is very persistent and adds the line again). Or Lazarus trunk introduces a new file structure, you must save every new project with checed "Maximize compatibility of project files" in "Project options" > "Miscellaneous"; otherwise the project will have no files in Laz 2.0.2 or older.

It is probably possible to cross compile from Windows to Linux (Gtk2) but this is difficult to setup because you need to copy a lot a Linux library to your Windows system. I don't know if Fpcupdeluxe can help with that?

The other way is much more easy because the win32 LCL do not expect the Windows DLL to be there for linking. So compiling for Win32 or Win64 from Linux is just a matter of changing the target in the build mode.

Patrick

Patrick Chevalley wrote

It is probably possible to cross compile from Windows to Linux (Gtk2) but this is difficult to setup because you need to copy a lot a Linux library to your Windows system. I don't know if Fpcupdeluxe can help with that? The other way is much more easy because the win32 LCL do not expect the Windows DLL to be there for linking. So compiling for Win32 or Win64 from Linux is just a matter of changing the target in the build mode.

OK, I see...
Meanwhile I have installed 2.0.2 as you suggested with the cross-compiler and used OPM to get Indy installed and then manually installed the PasLibVlc package.
Next I opened the old project and built the two targets WIn 32 and 64 and it all went well!

So I will start uninstalling the old versions now (freeing up 6+ GB of disk), and I also found Lazarus 1.4 in my disk...