Compile ruby for iPhone SDK

build_ruby_for_ios.sh

#!/bin/bash

# First, install Xcode and accompanying command-line tools

wget https://cache.ruby-lang.org/pub/ruby/3.0/ruby-3.0.2.tar.gz
tar -zxvf ruby-3.0.2.tar.gz

cd ruby-3.0.2

./configure --prefix=/tmp \
  --build=x86_64-apple-darwin20 \
  --target=aarch64-apple-darwin20 \
  --with-gmp=/usr/local/opt/gmp \
  --with-mpfr=/usr/local/opt/mpfr \
  --with-mpc=/usr/local/opt/libmpc \
  --with-isl=/usr/local/opt/isl \
  --with-native-system-header-dir=/usr/include \
  --with-sysroot=$(xcrun --sdk iphoneos --show-sdk-path) \
  AS_FOR_TARGET=/usr/bin/as LD_FOR_TARGET=/usr/bin/ld \
  NM_FOR_TARGET=/usr/bin/nm RANLIB_FOR_TARGET=/usr/bin/ranlib \
  AR_FOR_TARGET=/usr/bin/ar LIPO_FOR_TARGET=/usr/bin/lipo \
  --disable-multilib

# makes a fat binary that supports all the given archs
make CC="$(xcrun --sdk iphoneos --find clang) -fdeclspec -isysroot $(xcrun --sdk iphoneos --show-sdk-path) -arch armv7 -arch armv7s -arch arm64"

# ruby and headers, etc will be placed in the /tmp directory
make install

# Sources:
# https://www.ruby-lang.org/en/documentation/installation/#building-from-source
# https://github.com/iains/gcc-darwin-arm64/issues/34
# https://coderwall.com/p/heonhw/compiling-for-ios-outside-of-xcode-with-xcrun

# Can we package ruby as an iOS Framework and/or Swift package?
# https://github.com/carsonmcdonald/ios-ruby-embedded (check out the Rakefile)
# https://www.raywenderlich.com/17753301-creating-a-framework-for-ios
# https://forums.swift.org/t/packaging-static-library-in-spm-package-for-ios-executable/41245/5
# https://developer.apple.com/documentation/swift_packages/distributing_binary_frameworks_as_swift_packages