ZSystems

Using LLVM15, I get a bit further - meaning that I get a running ldc2/ldmd2 compiler, BUT no runtime library (phobos). (One can't just (re)use the Phobos lib that's already available for gdc/gdmd - at least not to my knowledge - as it is highly compiler-specific.

Steps were:

• Unpack 1.32.0 tarball
• create dedicated build dir and cd into it
• Run the following command in order to create Ninja build files from CMake: cmake -G Ninja .. \ -DCMAKE_BUILD_TYPE=Release \ -DCMAKE_INSTALL_PREFIX=$PWD/../install-ldc \ -DLLVM_CONFIG=/bin/llvm-config \ -DD_COMPILER=gdmd
• Run ninja in order to start the build

This way, one gets a bin subdir containing the compiler binaries and the corresponding config file (the paths therein are relative; specific to the build. Thus, the config is
not generally usable outside of the build environment). These binaries are usable. Proof:

~/src/ldc-1.32.0-src/build-ldc/bin$ ./ldc2 --version                                                                                         0:47:37
LDC - the LLVM D compiler (1.32.0):
  based on DMD v2.102.2 and LLVM 15.0.7
  built with gdc (SUSE Linux) 13.0.1 20230314 (experimental) [revision 42630fadbe248717859d61c0244c821c32b4e52c]
  Default target: s390x-suse-linux
  Host CPU: z15
  http://dlang.org - http://wiki.dlang.org/LDC

  Registered Targets:
    bpf     - BPF (host endian)
    bpfeb   - BPF (big endian)
    bpfel   - BPF (little endian)
    systemz - SystemZ
    wasm32  - WebAssembly 32-bit
    wasm64  - WebAssembly 64-bit

~/src/ldc-1.32.0-src/build-ldc/bin$ ldd ldc2                                                                                                 0:48:13
    linux-vdso64.so.1 (0x000003ffd1f89000)
    libLLVM.so.15 => /lib64/libLLVM.so.15 (0x000003ffb5700000)
    libgphobos.so.4 => /lib64/libgphobos.so.4 (0x000003ffb4c00000)
    libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x000003ffbb500000)
    libm.so.6 => /lib64/libm.so.6 (0x000003ffbac00000)
    libc.so.6 => /lib64/libc.so.6 (0x000003ffb4900000)
    libstdc++.so.6 => /lib64/libstdc++.so.6 (0x000003ffb4500000)
    libedit.so.0 => /lib64/libedit.so.0 (0x000003ffb5680000)
    libz.so.1 => /lib64/libz.so.1 (0x000003ffb5600000)
    /lib/ld64.so.1 (0x000003ffbb600000)
    libtinfo.so.6 => /lib64/libtinfo.so.6 (0x000003ffb4b80000)

~/src/ldc-1.32.0-src/build-ldc/bin$ ./ldmd2 --version                                                                                        0:49:02
LDC - the LLVM D compiler (1.32.0):
  based on DMD v2.102.2 and LLVM 15.0.7
  built with gdc (SUSE Linux) 13.0.1 20230314 (experimental) [revision 42630fadbe248717859d61c0244c821c32b4e52c]
  Default target: s390x-suse-linux
  Host CPU: z15
  http://dlang.org - http://wiki.dlang.org/LDC

  Registered Targets:
    bpf     - BPF (host endian)
    bpfeb   - BPF (big endian)
    bpfel   - BPF (little endian)
    systemz - SystemZ
    wasm32  - WebAssembly 32-bit
    wasm64  - WebAssembly 64-bit

:~/src/ldc-1.32.0-src/build-ldc/bin$ ldd ldmd2                                                                                                0:49:41
    linux-vdso64.so.1 (0x000003ffc7ea4000)
    libLLVM.so.15 => /lib64/libLLVM.so.15 (0x000003ff9a400000)
    libgphobos.so.4 => /lib64/libgphobos.so.4 (0x000003ff99900000)
    libgcc_s.so.1 => /lib64/libgcc_s.so.1 (0x000003ff9f900000)
    libm.so.6 => /lib64/libm.so.6 (0x000003ff9a300000)
    libc.so.6 => /lib64/libc.so.6 (0x000003ff99600000)
    libstdc++.so.6 => /lib64/libstdc++.so.6 (0x000003ff99200000)
    libedit.so.0 => /lib64/libedit.so.0 (0x000003ff99880000)
    libz.so.1 => /lib64/libz.so.1 (0x000003ff99580000)
    /lib/ld64.so.1 (0x000003ff9fa80000)
    libtinfo.so.6 => /lib64/libtinfo.so.6 (0x000003ff99500000)

The error msg dor the ninja build refers to a failing assertion - the last build cmd executed was:

cd /home/linux1/src/ldc-1.32.0-src/runtime/druntime/src && /home/linux1/src/ldc-1.32.0-src/build-ldc/bin/ldc2 -c --output-o -conf= -w -de -preview=dip1000 -preview=dtorfields -preview=fieldwise -g -link-defaultlib-debug -d-debug -I/home/linux1/src/ldc-1.32.0-src/runtime/druntime/src -od=/home/linux1/src/ldc-1.32.0-src/build-ldc/runtime/objects-debug -op <lots_of_d_src_files>

The error msg is:

rt/sections_elf_shared.d(1198): Error: static assert:  "Platform not supported."
ninja: build stopped: subcommand failed.

The path to the file in question is:

~/src/ldc-1.32.0-src$ find . -type f -name sections_elf_shared.d                                                                             0:53:03
./runtime/druntime/src/rt/sections_elf_shared.d

(I ain't got the platform-specific (z15 in specific / s390x in general) architectural knowledge to make the necessary contributions).

What's also worth mentioning is that there indeed is an ldc package in the devel:lanaguages:D project.
BUT: After having branched (and trying to build) that, I get:

[    8s] + exec rpmbuild -ba --define '_srcdefattr (-,root,root)' --nosignature --undefine _enable_debug_packages /home/abuild/rpmbuild/SOURCES/ldc.spec
[    9s] error: Architecture is not included: s390x

(At that point, I'm not sure whether it's better to continue working from/with the "plain" tarball (unpacked, of course ;-) ) or try to get the official package
build - at least - to the point where I get working ldc2/ldmd2 executables for s390x/z15.)