Free Pascal Wiki
Please note that all information detailed here is specific to Free Pascal 3.x and above, and does not apply to the older existing AROS Free Pascal 1.x port, nor does it apply to the older 0.99.x and 1.0.x versions of Free Pascal for classic Amiga/68k.
However, this port is very closely related to the recent supported classic Amiga/68k and MorphOS platforms as they share some of the same code with AROS in an attempt to unify the support in Free Pascal for these platforms.
This port is aimed at AROS (AROS Research Operating System), the open source implementation of the "classic Amiga operating system", which runs on modern processors like x86/x64/arm and PPC.
Because AROS is API compatible with Amiga (and binary compatible with Amiga 68k), there is much similarity when addressing Classic Amiga, MorphOS and AROS (all of which are supported by Free Pascal).
Free Pascal for AROS has its own Wiki page here (under slow and continues development).
An initial AROS contribution regarding a port of Free Pascal version 1.x was done by sasu in 2002, which was (partially) based on the support units for the Amiga 68k port of Free Pascal which in its own turn was mostly the work of Nils Sjoholm. Further development of this port ceased quickly thereafter.
A fresh new port based on Free Pascal 2.5.1 was anounced by ALB42 in the first half of 2011, which was again (partially) based on the Amiga 68k support units from Nils Sjoholm.
In xxxx, Karoly, better known for his ports of Free pascal to MorphOS and classic Amiga(OS), offered a helping hand. In 2014 this led to the start of integrating the supported 3 Amiganoid systems into the FPC 2.7.1 trunk.
As of FPC 3.0 release, AROS/i386 is officially supported as a target by Free Pascal.
- 2002-02-19 sasu ported Free Pascal 1.1 to AROS and commited his work into AROS Contrib repo 
- 2007-01-02 Not being actively developed and for saving build time and space, Free Pascal was removed from AROS Contrib. 
- 2011-04-18 ALB42 announced to have been working on a port of FPC 2.5 for AROS. 
- 2011-05-30 ALB42 makes his initial work on his port of Free Pascal 2.5.1 for AROS available to public. 
- 2011-06-18 ALB42 releases his initial progress on a native LCL implementation for AROS to public. 
- 2011-08-06 With commit of revision r18107 by Florian, AROS received its own branch in FPC sources. 
- more dates currently missing
- Most FPC rtl functions are supported
- AROS ABIv1 support is not implemented yet, see classic Amiga for now. (missing link)
- FPC sources are as much source compatible to AmigaOS 68k as possible, and could therefor be cross-compiled for Amiga 68k (if not using AROS specific functionality).
- The (cross) compiler is available for multiple platforms, including AROS/i386, Windows32/64 and linux32/64
- AROS Binutils are available
- Threads are not fully supported yet
- Executeprocess is not supported yet
- Support for fpGUI (native and LCL) was added by ALB42 in 2014 (working partially, in development)
- Support for Lazarus/MUI widgets was (re)started in 2014 by ALB42 (currently in early development, but very usable).
More elaborating status pages can be viewed on the Free Pascal for AROS wiki. (link is missing)
The current (cross) compiler is able to create AROS executables for AROS/i386 (abiv0).
Specific defines for AROS are - AROS - LCL_MUI (use LCL/MUI widgetset implementation), if omitted use fpGUI//LCL implemntation
Every operating system derived from or based upon classic AmigaOS, is neither Windows nor Linux. This results in paths being treated differently. Amiga/AROS/MorphOS uses the format "Drive Name:Directory 1/Subdirectory/Name of a file.extention" (without the quotes). Please keep this in mind when developing software that is intended to run cross-platform.
Requirements to start developing for AROS
- An AROS installation in case testing of the executables is required.
- Free Pascal for AROS, or (cross)compiler for a supported platform (Windows, Linux, Others ?).
- The AROS binutils (standard installed by most distros)
- No other dependencies required, but for completeness the AROS NDK.
Native development and/or testing executables is possible by installing AROS into a virtual machine, running AROS hosted (as single application) under Linux/Windows or on a dedicated AROS machine. All of which require minimal i386 processor.
- AROS homepage 
- AROS wikibook 
- AROS Support forums 
- Free Pascal for AROS wiki 
- Free Pascal for AROS FAQ (Short Introduction for those unfamiliar with AROS). (page needs verification and wiki-integration before adding link).
- Free Pascal for AROS Online reference  (not up to date, we could use some help)