mruby 2.1.2 Release Notes

We are announcing the stable release of mruby 2.1 series - mruby 2.1.2.

New Features

Core Language Features

• Support for Argument Forwarding, which allows you to forward argyments in the form def foo(...).

mruby VM and bytecode

• Add OP_LOADI16 instruction that loads a 16-bit integer into a register.
• Remove endian information/flags from compiled binary format.
• The version of the mruby binary has changed from 0006 to 0007.

for mruby Developer

• Add new C APIs.
  • mrb_float_to_cstr() - Convert Float to C String.
  • mrb_singleton_class_ptr() - Get pointer of Singleton class. #4973
  • mrb_utf8len() - Get size of UTF-8 string. #4712
  • mrb_utf8_strlen() - Get length of UTF-8 string. #4712
  • mrb_get_arg1() - Retrieve the first and only argument from mrb_state.

Update Features

Core Libraries

• Add to the libraries included by default in the mruby VM.
  • mruby-eval
  • mruby-complex
  • mruby-rational
• Support MRB_DISABLE_STDIO for mruby-pack and mruby-sprintf. #4954
• Support IO#pread and IO#pwrite on macOS.
• Improve Kernel.#eval to call method with the same name as a variable name without any arguments.
• IO#readchar supports UTF-8 characters.

Tools

• Remove -e / -E options from mrbc.

for mruby Developer

• Support width specifier with mrb_float_to_str().
• Support integer and float combination in mrb_equal().

Improve mruby build

• A mruby can be built without GNU Bison. (a3ec6ede)
• Supports GitHub Actions. #4903
  Execute CI of the following platforms updating the repository.
  • Ubuntu 16.04
  • Ubuntu 18.04 (gcc)
  • Ubuntu 18.04 (clang)
  • macOS
  • Windows (MinGW)
  • Windows (Cygwin)
  • Windows (MSVC)

Breaking Changes

• IO#readchar returns a UTF-8 character fragment instead of EOFError if EOF is reached in the middle of UTF-8 characters. (86271572)
  This behavior is different from CRuby, but it is a mruby specification that supports either ASCII or UTF-8 exclusively.
• Remove mrb_run() from C APIs.

Major bug fixes

• Segmentation fault at mrb_io_s_select. #4966
• Segmentation fault at mrb_vm_exec. #4973
• Some Hash methods are inconsistent with values when hash has duplicate key. 181f7b97
• Get local variable names from orphan block. #5014
• Memory leaks in some places when out of memory. f1523d24
• Heap buffer overflow in mruby interpreter. #5042
• Type tag not used when calculating hash code. #5049