Hi all!

I'm studying how to add a new target for the Freepascal compiler. The target is the missing armhf-FreeBSD. So I have looked at FPC guide ( https://wiki.freepascal.org/Porting_Free_Pascal#Adding_a_new_target) and looking at Overview section, item 2 says:

"Take the closest existing RTL as a start, copy it and start implementing"

I was thinking of starting with armhf-netbsd, that can I suppose to be the closest to the armhf-freebsd target. I'm right? Someone experienced adding new targets for FPC has another suggestion?

You need to add support of a new CPU to the existing freebsd target. The target would be arm-freebsd, since armhf is not treated as a separate CPU by FPC. You need to create arm startup files in the rtl/freebsd/arm folder.

Yuriy.

Yes, I know. But to add this new CPU support for the FPC/FreeBSD, it is better I start with files of rtl/freebsd/i386 or rtl/freebsd/x86_64 or use another start point, like rtl/netbsd/arm ?

The primary goal of a startup code is to get pointers to the command line parameters and the environment block. If arm-freebsd uses the stack to pass these pointers (the same way as i386-freebsd), then you need just to convert the i386 startup assembly to the arm assembly.
For start you need only the prt0.as file.

Yuriy.

Thanks for the hints!

Op 28/01/2020 om 18:08 schreef Fabio Luis Girardi via fpc-pascal:

That was written from the perspective of a new OS.

For adding a new architecture to an existing OS, probably the files systems/i_bsd.pas and t_bsd.pas are the main files.

A record with settings needs to be added to i_bsd and the calling of assembler and linker needs to be checked in t_bsd.

I strongly recommend to create pascal startup files for newly added targets.

Hi,

Fabio Luis Girardi wrote

I was thinking of starting with armhf-netbsd, that can I suppose to be the closest to the armhf-freebsd target. I'm right? Someone experienced adding new targets for FPC has another suggestion?

Well, you don't need to clone the entire RTL for just porting the thing to a different CPU architecture, if the OS support is already there, so I wouldn't follow that advice. And I'd just extend the existing FreeBSD RTL and for that, I could use the NetBSD one. They're heavily overlap anyway.

However, you need to add the new target it to the build system, and the compiler, which is quite complicated, as a system ID and various properties have to be added to quite a few places (compiler, /systems/t_bsd.pas, systems.pas, ppudump, FPMake and FPCMake, then regenerate all the Makefiles...) So it's quite an undertaking, not really feasible for submitting a simple patch. However, if you want I can assist in that part, so you can just iterate on the RTL, by having a working compiler already.

BTW the NetBSD/ARMHF port (by me, if I'm correct), was never really working fully, because I was too lazy to figure out some things, like the usual "always broken on BSD" differences in the stat structure, and how some syscalls have changed.

But maybe it's a time to figure out what's up with that. I still have the required NetBSD setup for that anyway.

Charlie

Hi,

There was some extra section on BSDs identifying which syscall version the binary uses, and some other stuff, IIRC. Which makes it difficult to add a Pascal startup code. But the assembly part can be minimized indeed. Not sure if that can be added by the internal assembler. Probably it can be generated by the compiler though?

Also there was some other thing with weak references I don't remember.

Charlie

Karoly Balogh (Charlie/SGR) schrieb am Mi., 29.
Jan. 2020, 01:22:

As a little anecdote: submitting a patch for a new target was exactly how I have started (and it was a completely new target, so more changes), so I wouldn't say that this isn't feasible for a patch ;) ( https://bugs.freepascal.org/view.php?id=14886 )

Regards,
Sven

Dear specialists,
Does somebody of you know, if it would be possible to build functional Android app from PPCJVM created .class files which will not depend on App compat jar library?
I have found two fully functional solutions, which do not used appcompat library.
Scatter on GOogle Play named create Android apps and one Termux project, which have been created by MR Sdrausty. It build .apk packages with minimal dependencies and fully functional, .dex sizes can be 40 100 KB, ETC.

But unfortunately, there is very very few projects, which can build .dex files from .class files, which have been created by Free Pascal compiler. My goal is to reduce memory allocations and increase GUI speed while touching screen with Android accessibility suite. I believe, that if resulting app have minimal dependencies, it allocates less memory and its GUI responsiveness can be much more faster.
Mr Sven Bard have created one functional app several ayears ago. it was metro organizer app.
It is very sad, that nobody have released good Android app builder which is based on PPCJVM, it would allow developers to create very small applications.