porting.txt

Porting is much easier than it used to be.

Countless things are no longer required.

As long as you are porting to just another processor,
but not another OS, e.g. NT, Linux, Darwin, Solaris, etc.
there is almost nothing to do.

You need to know endian (big or little), word size (32 or 64).

Here is a good example, of just adding another Linux port:


C:\s\cm3>git grep -i riscv

optional but nice, trivial         : .gitignore:RISCV64_LINUX
not needed                         : m3-libs/libm3/src/os/POSIX/m3makefile-old2:    "RISCV64" : "riscv64",
important or will get compile error: m3-libs/m3core/src/runtime/POSIX/RTSignalC.c:#elif defined(__riscv) || defined(__riscv64)
important, create a little file like this:
  m3-sys/cminstall/src/config-no-install/RISCV64.common:readonly TARGET_ARCH = "RISCV64"
  m3-sys/cminstall/src/config-no-install/RISCV64_LINUX:readonly TARGET = "RISCV64_LINUX" % code generation target
  m3-sys/cminstall/src/config-no-install/RISCV64_LINUX:% readonly GNU_PLATFORM = "riscv64-linux" % "cpu-os" string for GNUm3-sys/cminstall/src/config-no-install/RISCV64_LINUX:include("RISCV64.common")

important for ease of porting and using:
  scripts/python/pylib.py:                 "SPARC64", "MIPS32", "MIPS64EL", "MIPS64", "PA32", "PA64", "RISCV64", "SH"]:
  scripts/python/pylib.py:    return a.endswith("_nt") or a.startswith("arm64") or a.startswith("riscv")

optional: scripts/python/targets.txt:RISCV64_LINUX

no longer useful:
  www/uploaded-archives/targets.txt:RISCV64_LINUX

Because the Modula-3 system including the compiler is written in Modula-3, you need a working Modula-3 install.
You will do a partial cross build.
Make a git branch.
Update those files.
Commit.
cd scripts/python
./boot1.py <the name of your new system>
This will produce cm3-boot-<your new system>-<timestamp>.tgz.
Copy that to your system.
Your native system must have make + C compiler and linker.
Extract cm3-boot.tgz
cd cm3-boot.
make
./cm3
 make sure it kinda runs
sudo mkdir -p /cm3/bin
mv cm3 /cm3/bin
export PATH=/cm3/bin:$PATH
git clone on the new system
cd scripts/python
./boot2.py
Voila.
./make-dist.py
Put a release on github.

This will possibly be even easier in future.

This is using the C backend.
If you want to use gcc or other, you may have significant more work to do.