cross-compiling on Linux to macOS target

[efa]

hi,
I want try to cross-build from Linux to macOS.
This is something I regularly do for c files, so if hbmk2 can leave the .c file in tmp, I can manually cross-compile to both x64 and arm64
Please add an option to not delete temporary .c files

[alcz]

There is incremental build mode which leaves those files.
Use hbmk2 -inc option or the same option in .hbp file, it will then put your .c files in .hbmk/ subdir.
You can also setup cross compiling Harbour environment so that hbmk2 executes your .c cross compiler. Even if you prefer manually executing that, you will later need cross compiled Harbour libs anyway.

For cross compiling you need to setup few environment variables before
https://groups.google.com/g/harbour-devel/c/-MKTZ8eHBxU/m/Seez9Iw14V4J
https://groups.google.com/g/harbour-devel/c/gt4OPyThLhA/m/aleR6vFXAiUJ

Please search or ask harbour-devel, harbour-users mailing lists for some examples.

[lailton]

You can combine too with -workdir=output_folder
examples:
https://github.com/harbour/core/search?q=workdir&type=code

[efa]

Following your hints, I made some basic tests.
I set the env vars as so:

 export OSXROOT=/opt/osxcross
 export OSX=$OSXROOT/target/bin
 export OHOST=x86_64-apple-darwin18
 export OCROSS=$OHOST-

 export HB_BUILD_3RDEXT=no
 export HB_BUILD_CONTRIBS=no
 export HB_BUILD_DYN=no
 export HB_BUILD_NAME=$OHOST
 export HB_CCPATH=$OSX
 export HB_CCPREFIX=$OCROSS
 export HB_COMPILER=clang
 export HB_CPU=x86-64
 export HB_HOST_BIN=~/c/harbour-core/bin/linux/gcc
 export HB_PLATFORM=darwin
 export HB_WITH_CURSES=no
 export HB_USER_LDFLAGS="-L$OSXROOT/target/lib/"

I can compile the .c sources to .o and I can confirm are darwin obj:

$ file hello.o _hbmkaut_hello.o
hello.o:          Mach-O 64-bit x86_64 object, flags:<|SUBSECTIONS_VIA_SYMBOLS>
_hbmkaut_hello.o: Mach-O 64-bit x86_64 object, flags:<|SUBSECTIONS_VIA_SYMBOLS>

but the link stage stop.
The first thing that is missing is the lib 'hbextern' (and maybe the other follow) built for macOS/darwin:

$ ~/c/harbour-core/bin/linux/gcc/hbmk2 -workdir=. -inc hello.prg
hbmk2: Processing environment options: -plat=darwin -comp=clang -cpu=x86-64
       -build=x86_64-apple-darwin18
hbmk2: Compiling Harbour sources...
Harbour 3.2.0dev (r-2084736466)
Copyright (c) 1999-2021, https://harbour.github.io/
Compiling 'hello.prg'...
Lines 7, Functions/Procedures 1
Generating C source output to './hello.c'... Done.
hbmk2: Compiling...
hbmk2: Linking... hello
ld: library not found for -lhbextern
clang: error: linker command failed with exit code 1 (use -v to see invocation)
hbmk2: Error: Running linker. 1
x86_64-apple-darwin18-clang ./hello.o './_hbmkaut_hello.o'  -L/opt/osxcross/target/lib/ -lhbextern -lhbdebug -lhbvm -lhbrtl -lhblang -lhbcpage -lgtcgi -lgtpca -lgtstd -lgttrm -lhbrdd -lhbuddall -lhbusrrdd -lrddntx -lrddcdx -lrddnsx -lrddfpt -lhbrdd -lhbhsx -lhbsix -lhbrtl -lhbvm -lhbmacro -lhbcplr -lhbpp -lhbcommon -lm -lpcre -lz   -Wl,-headerpad,400 -o hello -L'/home/efa/c/harbour-core/lib'

I see there are no release/tag on github, are there some (recent) pre-built library mach/x86-64 (and maybe arm64) .a/.dylib, so I can avoid to cross-build all the harbour env, maybe I unable to do?
THANKS

[efa]

I saw the file harbour-1.0.1-darwin_9.5.0.bin.tar.gz at:
https://sourceforge.net/projects/harbour-project/files/binaries-osx/1.0.1/
is dated 2008, and I checked the .a lib inside ./usr/local/lib/harbour/, it miss:
hbuddall
rddnsx

[alcz]

Don't use those old libraries.
Depending on how complete your toolchain is (macOS system libs, headers), you should be able to build cross-compiled libraries with those settings just by issuing make.
Lately nobody contributed automatic build configurations, i think macOS binaries could be even built by Github Actions. I can make a one time build on a random x64 mac here, i'll share a link when it's done.

[alcz]

Not warranties whatsoever, but here they are.
https://os.allcom.pl/hb/bin/harbour-3.2.0dev-r2211112015-darwin.bin.tar.gz
https://os.allcom.pl/hb/bin/harbour-3.2.0dev-r2211112015-darwin.binsrc.tar.gz

Harbour Build Info
---------------------------
Version: Harbour 3.2.0dev (r2211112015)
Compiler: LLVM/Clang C 12.0 (clang-1200.0.32.29) (64-bit)
Platform: Darwin 19.6.0 x86_64
PCode version: 0.3
ChangeLog last entry: 2022-11-11 21:15 UTC+0100 Przemyslaw Czerpak (druzus/at/poczta.onet.pl)
ChangeLog ID: 9d578a24e6d5a2c3d20b68026b49147b4ccbb9cb
Built on: Nov 13 2022 19:37:05
Build options: (Clipper 5.3b) (Clipper 5.x undoc) 

[efa]

I got another link error:

$ ~/c/harbour-core/bin/linux/gcc/hbmk2 -workdir=. -inc hello 
hbmk2: Processing environment options: -plat=darwin -comp=clang -cpu=x86-64
       -build=x86_64-apple-darwin18
hbmk2: Processing local make script: hbmk.hbm
hbmk2: Compiling Harbour sources...
Harbour 3.2.0dev (r-2084736466)
Copyright (c) 1999-2021, https://harbour.github.io/
Compiling 'hello.prg'...
Lines 7, Functions/Procedures 1
Generating C source output to './hello.c'... Done.
hbmk2: Compiling...
hbmk2: Linking... hello
Undefined symbols for architecture x86_64:
  "___darwin_check_fd_set_overflow", referenced from:
      _hb_fsCanAccess in libhbrtl.a(filesys.o)
      _hb_fsPoll in libhbrtl.a(filesys.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
hbmk2: Error: Running linker. 1
x86_64-apple-darwin18-clang ./hello.o './_hbmkaut_hello.o'  -L/home/efa/c/harbour.src/lib/darwin/clang -L/opt/osxcross/target/lib/ -lhbextern -lhbdebug -lhbvm -lhbrtl -lhblang -lhbcpage -lgtcgi -lgtpca -lgtstd -lgttrm -lhbrdd -lhbuddall -lhbusrrdd -lrddntx -lrddcdx -lrddnsx -lrddfpt -lhbrdd -lhbhsx -lhbsix -lhbrtl -lhbvm -lhbmacro -lhbcplr -lhbpp -lhbcommon -lm -lpcre -lz   -Wl,-headerpad,400 -o hello -L'/home/efa/c/harbour-core/lib'

Now I'm generating the Darwin19 osxcross compiler tools to see if make difference, as my toolchain target 18 while I saw you used 19

[efa]

OK, now work:

$ ~/c/harbour-core/bin/linux/gcc/hbmk2 -workdir=. -inc hello 
hbmk2: Processing environment options: -plat=darwin -comp=clang -cpu=x86-64
       -build=x86_64-apple-darwin19
hbmk2: Processing local make script: hbmk.hbm
hbmk2: Compiling Harbour sources...
Harbour 3.2.0dev (r-2084736466)
Copyright (c) 1999-2021, https://harbour.github.io/
Compiling 'hello.prg'...
Lines 7, Functions/Procedures 1
Generating C source output to './hello.c'... Done.
hbmk2: Compiling...
hbmk2: Linking... hello

$ file hello
hello: Mach-O 64-bit x86_64 executable, flags:<NOUNDEFS|DYLDLINK|TWOLEVEL|PIE>

$ ls -l hello
-rwxr-xr-x 1 efa efa 1191000 Nov 17 22:55 hello

Will try to build something more complex now, with other deps.

Did you have an arm64 build too?

[efa]

I can say the cross-build from harbour source to macOS/x86_64 work well using CLANG and OSXCROSS: https://github.com/tpoechtrager/osxcross
Maybe you can flag Linux to macOS as supported in the platform matrix: https://github.com/harbour/core#platform-matrix

Now I want try build a binary for Apple Silicon.
Did you have the harbour lib built for ARM64 ?

thank you in advance

[lailton]

@efa,
Here you have harbour for mac arm64:
https://drive.google.com/file/d/1k_F5ZznwxBayYGI7_AQl1tWqk6WcUOYj/view?usp=share_link

[alcz]

Thanks for reporting! Good to know that it's possible to make such cross-build. Seems more practical for automated builds than personal usage.

[efa]

@efa, Here you have harbour for mac arm64: https://drive.google.com/file/d/1k_F5ZznwxBayYGI7_AQl1tWqk6WcUOYj/view?usp=share_link

what Darwin version do you use? 20, 21 or 22?
I'm trying with: macOS/SDK 11.1, Xcode 12.3 , darwin 20.2

[efa]

found, confirm do you used macOS 13.0 ?

[efa]

I got lot of warnings in the link phase:
ld: warning: object file (/home/efa/c/harbour_macOS.arm64/harbour_arm64/lib/darwin/clang/libhbrtl.a(arc4.o)) was built for newer macOS version (13.0) than being linked (11.1)
but the binary is generated and is a macOS/arm64:

$ file hello
hello: Mach-O 64-bit arm64 executable, flags:<NOUNDEFS|DYLDLINK|TWOLEVEL|PIE>