Compiling Pascal code with Lazarus LCL in Linux

Question

I am trying to compile/port on Linux a project which was originally written in Delphi on Windows. I have zero experience with Delphi on Windows and I have only very limited experience with Pascal.

I am running in Ubuntu 22.04.3 LTS and I have installed system-provided Freepascal and Lazarus with sudo apt install fp-units-* lcl-* lazarus lcl fpc-* (I've reached this list by trials and errors which helped me making progress towards trivial errors).

When I try to compile the top level program file, it fails as follows:

$ fpc myprogr.dpr
Free Pascal Compiler version 3.2.2+dfsg-9ubuntu1 [2022/04/11] for x86_64
Copyright (c) 1993-2021 by Florian Klaempfl and others
Target OS: Linux for x86-64
Compiling myprogr.dpr
myprogr.dpr(4,3) Fatal: Can't find unit Forms used by myprogr
Fatal: Compilation aborted
Error: /usr/bin/ppcx64 returned an error exitcode

which is weird because the stuff is there:

$ dpkg -S /usr/lib/lazarus/2.2.0/lcl/forms.pp
lazarus-src-2.2: /usr/lib/lazarus/2.2.0/lcl/forms.pp
$ ls -l /usr/lib/lazarus/2.2.0/lcl/forms.pp 
-rw-r--r-- 1 root root 92597 Jan  2  2022 /usr/lib/lazarus/2.2.0/lcl/forms.pp

And that leads me to believe that something is wrong with the packages I am utilizing, but anyway I manually add the path, and the failure becomes:

$ fpc -Fu/usr/lib/lazarus/2.2.0/lcl/ myprogr.dpr
Free Pascal Compiler version 3.2.2+dfsg-9ubuntu1 [2022/04/11] for x86_64
Copyright (c) 1993-2021 by Florian Klaempfl and others
Target OS: Linux for x86-64
Compiling myprogr.dpr
Compiling /usr/lib/lazarus/2.2.0/lcl/forms.pp
forms.pp(24,2) Fatal: Cannot open include file "lcl_defines.inc"
Fatal: Compilation aborted
Error: /usr/bin/ppcx64 returned an error exitcode

Weird again as before because:

$ dpkg -S lcl_defines.inc
lazarus-src-2.2: /usr/lib/lazarus/2.2.0/lcl/include/lcl_defines.inc
$ ls -l /usr/lib/lazarus/2.2.0/lcl/include/lcl_defines.inc
-rw-r--r-- 1 root root 325 Jul 11  2020 /usr/lib/lazarus/2.2.0/lcl/include/lcl_defines.inc

which I can make again progress with:

$ fpc -Fu/usr/lib/lazarus/2.2.0/lcl/ -I/usr/lib/lazarus/2.2.0/lcl/include/ myprogr.dpr
Free Pascal Compiler version 3.2.2+dfsg-9ubuntu1 [2022/04/11] for x86_64
Copyright (c) 1993-2021 by Florian Klaempfl and others
Target OS: Linux for x86-64
Compiling myprogr.dpr
Compiling /usr/lib/lazarus/2.2.0/lcl/forms.pp
Compiling /usr/lib/lazarus/2.2.0/lcl/lclstrconsts.pas
Writing Resource String Table file: lclstrconsts.rsj
lclstrconsts.pas(481) Error: Writing Resource String Table file: > /usr/lib/lazarus/2.2.0/lcl/lclstrconsts.rsj
lclstrconsts.pas(481) Fatal: There were 1 errors compiling module, stopping
Fatal: Compilation aborted
Error: /usr/bin/ppcx64 returned an error exitcode

And that continues the weirdness because:

$ dpkg -S lclstrconsts.rsj
lcl-units-2.2: /usr/lib/lazarus/2.2.0/lcl/units/x86_64-linux/lclstrconsts.rsj
$ ls -l /usr/lib/lazarus/2.2.0/lcl/units/x86_64-linux/lclstrconsts.rsj
-rw-r--r-- 1 root root 77783 Apr 11  2022 /usr/lib/lazarus/2.2.0/lcl/units/x86_64-linux/lclstrconsts.rsj

on top of which why is the compiler trying to write in global location rather than locally, but I digress.

Of course I looked at the Freepascal, Lazarus and a bit at the Ubuntu/Debian documentation (as well as generic web search), and nothing seemed to indicate this sort of problems...

I can jump into the rabbit hole and continue to reverse engineer all of this which potentially might even succeed compiling the project as I need, but instead I'd rather ask: am I doing something obviously wrong? Is the Freepascal and Lazarus projects in my distro broken (which means, should I rather compile them from source)?

Answer 1

As @HeartWare as noticed in a comment, the root cause of the impossibility to move forward is that the code uses Windows, Forms and many other Microsoft-specific units which do not have a Linux equivalent. This is unfortunate, but the most unfortunate aspect is that it's not clear at all from reading the documentation as a newbie, where it sounds like they have ported all units for all OSes.

But the most time consuming issue is that to compile the code I need a whopping

fpc -Fu/usr/share/lazarus/2.2.2/lcl/                    \
    -Fu/usr/share/lazarus/2.2.2/components/lazutils/    \
    -Fu/usr/share/lazarus/2.2.2/lcl/widgetset/          \
    -Fu/usr/share/fpcsrc/3.2.2/rtl/linux                \
    -Fu/usr/share/lazarus/2.2.2/lcl/nonwin32/           \
    -Fu/usr/share/fpcsrc/3.2.2/packages/pasjpeg/src/    \
    -Fi/usr/share/lazarus/2.2.2/lcl/include/            \
    -Fi/usr/share/fpcsrc/3.2.2/rtl/inc/                 \
    -Fi/usr/share/fpcsrc/3.2.2/rtl/linux                \
    -Fi/usr/share/fpcsrc/3.2.2/rtl/x86_64/              \
    -Fi/usr/share/fpcsrc/3.2.2/rtl/unix/                \
    -Fi/usr/share/fpcsrc/3.2.2/rtl/win/                 \
    -Fi/usr/share/fpcsrc/3.2.2/rtl/linux/x86_64/        \
    -FU./lib                                            \
    -MDELPHI                                            \
     my.dpr

This is both with the OS-provided and with the freepascal.org-provided (binary) installation. Being familiar with several other programming languages, this sounds really counterintuitive, in that the stuff in /usr is always automatically included by the compilers/interpreters because so specified in some global configuration, e.g. /usr/include/ in C.

I still don't understand if that's the way it is for FreePascal or if it's something wrong with the binary installs for my OS which lack a global configuration setting.