CHANGELOG.md

22.0.0

New features:

Bug fixes:

• Fix File.utime to use nanoseconds (#2448).
• Capture the intercepted feature path during patching to reuse during patch require (#2441).
• Update Module#constants to filter invalid constant identifiers (#2452).
• Fixed -0.0 <=> 0.0 and -0.0 <=> 0 to return 0 like on CRuby (#1391).

Compatibility:

• Implement rb_sprintf in our format compiler to provide consistent formatting across C standard libraries.
• Update defined? to return frozen strings (#2450).
• Use compensated summation for {Array,Enumerable}#sum when floating point values are included.
• Module#attr_* methods now return an array of method names (#2498, @gogainda).

Performance:

• Regexp objects are now interned in a similar way to symbols.
• Improve performance of regexps using POSIX bracket expressions (e.g., [[:lower:]]) matching against ASCII-only strings (#2447).
• String#sub, sub!, gsub, and gsub! have been refactored for better performance.

Changes:

21.3.0

New features:

• TRegex is now used by default, which provides large speedups for matching regular expressions.
• Add Polyglot.languages to expose the list of available languages.
• Add Polyglot::InnerContext to eval code in any available language in an inner isolated context (#2169).
• Foreign objects now have a dynamically-generated class based on their interop traits like ForeignArray and are better integrated with Ruby objects (#2149).
• Foreign arrays now have all methods of Ruby Enumerable and many methods of Array (#2149).
• Foreign hashes now have all methods of Ruby Enumerable and many methods of Hash (#2149).
• Foreign iterables (InteropLibrary#hasIterator) now have all methods of Ruby Enumerable (#2149).
• Foreign objects now implement #instance_variables (readable non-invocable members) and #methods (invocable members + Ruby methods).

Bug fixes:

• Fix Marshal.load of multiple Symbols with an explicit encoding (#1624).
• Fix rb_str_modify_expand to preserve existing bytes (#2392).
• Fix String#scrub when replacement is frozen (#2398, @LillianZ).
• Fix Dir.mkdir error handling for Pathname paths (#2397).
• BasicSocket#*_nonblock(exception: false) now only return :wait_readable/:wait_writable for EAGAIN/EWOULDBLOCK like MRI (#2400).
• Fix issue with strspn used in the date C extension compiled as a macro on older glibc and then missing the __strspn_c1 symbol on newer glibc (#2406).
• Fix constant lookup when loading the same file multiple times (#2408).
• Fix handling of break, next and redo in define_method(name, &block) methods (#2418).
• Fix handling of incompatible types in Float#<=> (#2432, @chrisseaton).
• Fix issue with escaping curly braces for Dir.glob (#2425).
• Fix base64 decoding issue with missing output (#2435).
• Fix StringIO#ungetbyte to treat a byte as a byte, not a code point (#2436).
• Fix defined?(yield) when used inside a block (#2446).
• Fix a couple issues related to native memory allocation and release.

Compatibility:

• Implement Process::Status.wait (#2378).
• Update rb_str_modify and rb_str_modify_expand to raise a FrozenError when given a frozen string (#2392).
• Implement rb_fiber_* functions (#2402).
• Implement rb_str_vcatf.
• Add support for tracing allocations from C functions (#2403, @chrisseaton).
• Implement rb_str_catf.
• Search the executable in the passed env PATH for subprocesses (#2419).
• Accept a string as the pattern argument to StringScanner#scan and StringScanner#check (#2423).

Performance:

• Moved most of MonitorMixin to primitives to deal with interrupts more efficiently (#2375).
• Improved the performance of rb_enc_from_index by adding cached lookups (#2379, @nirvdrum).
• Improved the performance of many MatchData operations (#2384, @nirvdrum).
• Significantly improved performance of TRegex calls by allowing Truffle splitting (#2389, @nirvdrum).
• Improved String#gsub performance by adding a fast path for the string_byte_index primitive (#2380, @nirvdrum).
• Improved String#index performance by adding a fast path for the string_character_index primitive (#2383, @LillianZ).
• Optimized conversion of strings to integers if the string contained a numeric value (#2401, @nirvdrum).
• Use Truffle's ContextThreadLocal to speedup access to thread-local data.
• Provide a new fast path for rb_backref* and rb_lastline*functions from C extensions.

Changes:

• foreign_object.class on foreign objects is no longer special and uses Kernel#class (it used to return the java.lang.Class object for a Java type or getMetaObject(), but that is too incompatible with Ruby code).
• Java.import name imports a Java class in the enclosing module instead of always as a top-level constant.
• foreign_object.keys no longer returns members, use foreign_object.instance_variables or foreign_object.methods instead.
• foreign_object.respond_to?(:class) is now always true (before it was only for Java classes), since the method is always defined.

Security:

• Updated to Ruby 2.7.4 to fix CVE-2021-31810, CVE-2021-32066 and CVE-2021-31799.

21.2.0

New features:

• New TruffleRuby::ConcurrentMap data structure for use in concurrent-ruby (#2339, @wildmaples).

Bug fixes:

• Fix of different values of self in different scopes.
• Truffle::POSIX.select was being redefined repeatedly (#2332).
• Fix the --backtraces-raise and --backtraces-rescue options in JVM mode (#2335).
• Fix File.{atime, mtime, ctime} to include nanoseconds (#2337).
• Fix Array#[a, b] = "frozen string literal".freeze (#2355).
• rb_funcall() now releases the C-extension lock (similar to MRI).

Compatibility:

• Updated to Ruby 2.7.3. The resolv stdlib was not updated (resolv in 2.7.3 has bugs).
• Make interpolated strings frozen for compatibility with Ruby 2.7 (#2304, @kirs).
• require 'socket' now also requires 'io/wait' like CRuby (#2326).
• Support precision when formatting strings (#2281, @kirs).
• Make rpartition compatible with Ruby 2.7 (#2320, @gogainda).
• Include the type name in exception messages from rb_check_type (#2307).
• Fix Hash#rehash to remove duplicate keys after modifications (#2266, @MattAlp)
• Only fail rb_check_type for typed data, not wrapped untyped structs (#2331).
• Decide the visibility in Module#define_method based on self and the default definee (#2334).
• Configure mandir value in RbConfig::CONFIG and RbConfig::MAKEFILE_CONFIG (#2315).
• TruffleRuby now supports the Truffle polyglot Hash interop API.
• Implement Fiber#raise (#2338).
• Update File.basename to return new String instances (#2343).
• Allow Fiber#raise after Fiber#transfer like Ruby 3.0 (#2342).
• Fix ObjectSpace._id2ref for Symbols and frozen String literals (#2358).
• Implemented Enumerator::Lazy#filter_map (#2356).
• Fix LLVM toolchain issue on macOS 11.3 (#2352, oracle/graal#3383).
• Implement IO#set_encoding_by_bom (#2372, pawandubey).
• Implemented Enumerator::Lazy#with_index (#2356).
• Implement rb_backref_set.
• Fix Float#<=> when comparing Infinity to other #infinite? values.
• Implement date library as a C extension to improve compatibility (#2344).

Performance:

• Make #dig iterative to make it faster and compile better for calls with 3+ arguments (#2301, @chrisseaton, @jantnovi).
• Make Struct#dig faster in interpreter by avoiding exceptions (#2306, @kirs).
• Reduce the number of AST nodes created for methods and blocks (#2261).
• Fiber-local variables are much faster now by using less synchronization.
• Improved the performance of the exceptional case of String#chr (#2318, @chrisseaton).
• Improved the performance of IO#read_nonblock when no data is available to be read.
• TruffleSafepoint is now used instead of custom logic, which no longer invalidates JITed code for guest safepoints (e.g., Thread#{backtrace,raise,kill}, ObjectSpace, etc)
• Significantly improved performance of Time#strftime for common formats (#2361, @wildmaples, @chrisseaton).
• Faster solution for lazy integer length (#2365, @lemire, @chrisseaton).
• Speedup rb_funcallv*() by directly unwrapping the C arguments array instead of going through a Ruby Array (#2089).
• Improved the performance of several Truffle::RegexOperations methods (#2374, @wildmapes, @nirvdrum).

Changes:

• rb_iterate() (deprecated since 1.9) no longer magically passes the block to rb_funcall(), use rb_block_call() instead.

Security:

• Updated to Ruby 2.7.3 to fix CVE-2021-28965 and CVE-2021-28966.

21.1.0

New features:

• Access to local variables of the interactive Binding via language bindings is now supported: context.getBindings("ruby").putMember("my_var", 42); (#2030).
• VALUEs in C extensions now expose the Ruby object when viewed in the debugger, as long as they have not been converted to native values.
• Signal handlers can now be run without triggering multi-threading.
• Fibers no longer trigger Truffle multi-threading.

Bug fixes:

• Range#to_a wasn't working for long ranges (#2198, @tomstuart and @LillianZ).
• Show the interleaved host and guest stacktrace for host exceptions (#2226).
• Fix the label of the first location reported by Thread#backtrace_locations (#2229).
• Fix Thread.handle_interrupt to defer non-pure interrupts until the end of the handle_interrupt block (#2219).
• Clear and restore errinfo on entry and normal return from methods in C extensions (#2227).
• Fix extra whitespace in squiggly heredoc with escaped newline (#2238, @wildmaples and @norswap).
• Fix handling of signals with --single-threaded (#2265).
• Fix Enumerator::Lazy#{chunk_while, slice_before, slice_after, slice_when} to return instances of Enumerator::Lazy (#2273).
• Fix Truffle::Interop.source_location to return unavailable source sections for modules instead of null (#2257).
• Fix usage of Thread.handle_interrupt in MonitorMixin#mon_synchronize.
• Fixed TruffleRuby.synchronized to handle guest safepoints (#2277).
• Fix control flow bug when assigning constants using ||= (#1489).
• Fix Kernel#raise argument handling for hashes (#2298).
• Set errinfo when rb_protect captures a Ruby exception (#2245).
• Fixed handling of multiple optional arguments and keywords when passed a positional Hash (#2302).

Compatibility:

• Prepend the GraalVM LLVM Toolchain to PATH when installing gems (#1974, #1088, #1343, #1400, #1947, #1931, #1588).
• Installing the nokogiri gem now defaults to use the vendored libxml2 and libxslt, similar to CRuby, which means the corresponding system packages are no longer needed (#62).
• Implemented $LOAD_PATH.resolve_feature_path.
• Add Pathname#/ alias to Pathname#+ (#2178).
• Fixed issue with large Integers in Math.log (#2184).
• Updated Regexp.last_match to support Symbol and String parameter (#2179).
• Added support for numbered block parameters (_1 etc).
• Fixed String#upto issue with non-ascii strings (#2183).
• Implemented partial support for pattern matching (#2186).
• Make File.extname return '.' if the path ends with one (#2192, @tomstuart).
• Include fractional seconds in Time#inspect output (#2194, @tomstuart).
• Add support for Integer#[Range] and Integer#[start, length] (#2182, @gogainda).
• Allow private calls with self as an explicit receiver (#2196, @wildmaples).
• Fixed :perm parameter for File.write.
• Implemented Time#floor and #ceil (#2201, @wildmaples).
• Allow Range#include? and #member? with Time (#2202, @wildmaples).
• Implemented Comparable#clamp(Range) (#2200, @wildmaples).
• Added a Array#minmax to override Enumerable#minmax (#2199, @wildmaples).
• Implemented chomp parameter for IO.{readlines, foreach} (#2205).
• Implemented the Debug Inspector C API.
• Added beginless range support for Range#{new, bsearch, count, each, equal_value, first, inspect, max, min, size, cover?, include?, ===}.
• Added beginless range support for Array#{[], []=, slice, slice!, to_a, fill, values_at} (#2155, @LillianZ).
• Added beginless range support for String#{byteslice, slice, slice!} and Symbol#slice (#2211, @LillianZ).
• Added beginless range support for Kernel#{caller, caller_locations} and Thread#backtrace_locations (#2211, @LillianZ).
• Make rand work with exclusive range with Float (#1506, @gogainda)
• Fixed String#dump's formatting of escaped unicode characters (#2217, @meganniu).
• Switched to the io-console C extension from C ruby for better performance and compatibility in irb.
• Coerce the message to a String for BasicSocket#send (#2209, @HoneyryderChuck).
• Support buffer argument for UDPSocket#recvfrom_nonblock (#2209, @HoneyryderChuck).
• Fixed Integer#digits implementation to handle more bases (#2224, #2225).
• Support the inherit parameter for Module#{private, protected, public}_method_defined?.
• Implement Thread.pending_interrupt? and Thread#pending_interrupt? (#2219).
• Implement rb_lastline_set (#2170).
• Implemented Module#const_source_location (#2212, @tomstuart and @wildmaples).
• Do not call File.exist? in Dir.glob as File.exist? is often mocked (#2236, @gogainda).
• Coerce the inherit argument to a boolean in Module#const_defined? and Module#const_get (#2240).
• Refinements take place at Object#method and Module#instance_method (#2004, @ssnickolay).
• Add support for rb_scan_args_kw in C API (#2244, @LillianZ).
• Update random implementation layout to be more compatible (#2234).
• Set RbConfig::CONFIG['LIBPATHFLAG'/'RPATHFLAG'] like MRI to let $LIBPATH changes in extconf.rb work.
• Access to path and mode via rb_io_t from C has been changed to improve compatibility for io-console.
• Implemented the Time.at in: parameter.
• Implemented Kernel#raise cause parameter.
• Improved compatibility of Signal.trap and Kernel#trap (#2287, @chrisseaton).
• Implemented GC.stat(:total_allocated_objects) as 0 (#2292, @chrisseaton).
• ObjectSpace::WeakMap now supports immediate and frozen values as both keys and values (#2267).
• Call divmod when coercion to Float fails for #sleep (#2289, @LillianZ).

Performance:

• Multi-Tier compilation is now enabled by default, which improves warmup significantly.
• Improve the performance of checks for recursion (#2189, @LillianZ).
• Improve random number generation performance by avoiding synchronization (#2190, @ivoanjo).
• We now create a single call target per block by default instead of two.
• Some uses of class variables are now much better optimized (#2259, @chrisseaton).
• Several methods that need the caller frame are now always inlined in their caller, which speeds up the interpreter and reduces footprint.
• Pasting code in IRB should be reasonably fast, by updating to irb 1.3.3 and reline 0.2.3 (#2233).

Changes:

• Standalone builds of TruffleRuby are now based on JDK11 (they used JDK8 previously). There should be no user-visible changes. Similarly, JDK11 is now used by default in development instead of JDK8.
• The deprecated Truffle::System.synchronized has been removed.
• Java.synchronized has been removed, it did not work on host objects.

21.0.0

Release notes:

• The new IRB is quite slow when copy/pasting code into it. This is due to an inefficient io/console implementation which will be addressed in the next release. A workaround is to use irb --readline, which disables some IRB features but is much faster for copy/pasting code.

New features:

• Updated to Ruby 2.7.2 (#2004).

Bug fixes:

• Fix error message when the method name is not a Symbol or String for Kernel#respond_to? (#2132, @ssnickolay)
• Fixed setting of special variables in enumerators and enumerables (#1484).
• Fixed return value of Enumerable#count and Enumerable#uniq with multiple yielded arguments (#2145, @LillianZ).
• Fixed String#unpack for w* format (#2143).
• Fixed issue with Kernel#` when invalid UTF-8 given (#2118).
• Fixed issue with Method#to_proc and special variable storage (#2156).
• Add missing offset parameter for FFI::Pointer#put_array_of_* (#1525).
• Fixed issue with different Structs having the same hash values (#2214).

Compatibility:

• Implement String#undump (#2131, @kustosz)
• Errno constants with the same errno number are now the same class.
• Implement Enumerable#tally and Enumerable#filter_map (#2144 and #2152, @LillianZ).
• Implement Range#minmax.
• Pass more Enumerator::Lazy#uniq and Enumerator::Lazy#chunk specs (#2146, @LillianZ).
• Implement Enumerator#produce (#2160, @zverok)
• Implement Complex#<=> (#2004, @ssnickolay).
• Add warning for proc without block (#2004, @ssnickolay).
• Implemented FrozenError#receiver.
• Proc#<< and Proc#>> raises TypeError if passed not callable object (#2004, @ssnickolay).
• Support time and date related messages for Time (#2166).
• Updated Dir.{glob,[]} to raise ArgumentError for nul-separated strings.
• Kernel#lambda with no block in a method called with a block raises an exception (#2004, @ssnickolay).
• Implemented BigDecimal as C extension to improve compatibility.
• Comment lines can be placed between fluent dot now (#2004, @ssnickolay).
• Implemented rb_make_exception.
• **kwargs now accept non-Symbol keys like Ruby 2.7.
• Updated the Unicode Emoji version (#2173, @wildmaples).
• Added Enumerator::Yielder#to_proc.
• Implemented Enumerator::Lazy#eager.
• Updated Method#inspect to include paremeter information.
• Update Module#name to return the same frozen string.
• Implemented inherit argument for Module#autoload?.

Performance:

• Refactor and implement more performant MatchData#length (#2147, @LillianZ).
• Refactor and implement more performant Array#sample (#2148, @LillianZ).
• String#inspect is now more efficient.

Changes:

• All InteropLibrary messages are now exposed consistently as methods on Truffle::Interop (#2139). Some methods were renamed to match the scheme described in the documentation.

20.3.0

Bug fixes:

• Handle foreign null object as falsy value (#1902, @ssnickolay)
• Fixed return value of Enumerable#first with multiple yielded arguments (#2056, @LillianZ).
• Improve reliability of the post install hook by disabling RubyGems (#2075).
• Fixed top level exception handler to print exception cause (#2013).
• Fixed issue when extending FFI from File (#2094).
• Fixed issue with Kernel#freeze not freezing singleton class (#2093).
• Fixed String#encode with options issue (#2091, #2095, @LillianZ)
• Fixed issue with spawn when :close redirect is used (#2097).
• Fixed coverage issue when *eval is used (#2078).
• Use expanded load paths for feature matching (#1501).
• Fixed handling of post arguments for super() (#2111).
• Fixed SystemStackError sometimes replaced by an internal Java NoClassDefFoundError on JVM (#1743).
• Fixed constant/identifier detection in lexer for non-ASCII encodings (#2079, #2102, @ivoanjo).
• Fixed parsing of --jvm as an application argument (#2108).
• Fix rb_rescue2 to ignore the end marker (VALUE)0 (#2127, #2130).
• Fix status and output when SystemExit is subclassed and raised (#2128)
• Fix String#{chomp, chomp!} issue with invalid encoded strings (#2133).

Compatibility:

• Run at_exit handlers even if parsing the main script fails (#2047).
• Load required libraries (-r) before parsing the main script (#2047).
• String#split supports block (#2052, @ssnickolay)
• Implemented String#{grapheme_clusters, each_grapheme_cluster}.
• Fix the caller location for #method_added (#2059).
• Fix issue with Float#round when self is -0.0.
• Fix String#unpack issue with m0 format (#2065).
• Fix issue with File.absolute_path returning a path to current directory (#2062).
• Update Range#cover? to handle Range parameter.
• Fix String#{casecmp, casecmp?} parameter conversion.
• Fix Regexp issue which raised syntax error instead of RegexpError (#2066).
• Handle Object#autoload when autoload itself (#1616, @ssnickolay)
• Skip upgraded default gems while loading RubyGems (#2075).
• Verify that gem paths are correct before loading RubyGems (#2075).
• Implement rb_ivar_count.
• Implemented rb_yield_values2.
• Implemented Digest::Base#{update, <<} (#2100).
• Pass the final super specs (#2104, @chrisseaton).
• Fix arity for arguments with optional kwargs (#1669, @ssnickolay)
• Fix arity for Proc (#2098, @ssnickolay)
• Check bounds for FFI::Pointer accesses when the size of the memory behind is known.
• Implement negative line numbers for eval (#1482).
• Support refinements for #to_s called by string interpolation (#2110, @ssnickolay)
• Module#using raises error in method scope (#2112, @ssnickolay)
• File#path now returns a new mutable String on every call like MRI (#2115).
• Avoid infinite recursion when redefining Warning#warn and calling Kernel#warn (#2109).
• Convert objects with #to_path in $LOAD_PATH (#2119).
• Handle the functions being native for rb_thread_call_without_gvl() (#2090).
• Support refinements for Kernel#respond_to? (#2120, @ssnickolay)
• JCodings has been updated from 1.0.45 to 1.0.55.
• Joni has been updated from 2.1.30 to 2.1.40.

Performance:

• Calls with a literal block are no longer always split but instead the decision is made by the Truffle splitting heuristic.
• Symbol#to_proc is now AST-inlined in order to not rely on splitting and to avoid needing the caller frame to find refinements which apply.
• Symbol#to_proc is now globally cached per Symbol and refinements, to avoid creating many redundant CallTargets.
• Setting and access to the special variables $~ and $_ has been refactored to require less splitting.

Changes:

• Migrated from JLine 2 to JLine 3 for the readline standard library.

20.2.0

New features:

• Updated to Ruby 2.6.6.
• Use InteropLibrary#toDisplayString() to better display objects from other languages.
• Implement writing to the top scope for global variables (#2024).
• foreign_object.to_s now uses InteropLibrary#toDisplayString() (and still asString() if isString()).
• foreign_object.inspect has been improved to be more useful (include the language and meta object).
• foreign_object.class now calls getMetaObject() (except for Java classes, same as before).
• Add basic support for Linux ARM64.
• foreign_object.name = value will now call Interoplibrary#writeMember("name", value) instead of invokeMember("name=", value).
• Always show the Ruby core library files in backtraces (#1414).
• The Java stacktrace is now shown when sending SIGQUIT to the process, also on TruffleRuby Native, see Debugging for details (#2041).
• Calls to foreign objects with a block argument will now pass the block as the last argument.
• foreign.name will now use invokeMember if invocable and if not use readMember, see doc/contrib/interop_implicit_api.md for details.
• foreign.to_f and foreign.to_i will now attempt to convert to Ruby Float and Integer (#2038).
• foreign.equal?(other) now uses InteropLibrary#isIdentical(other) and foreign.object_id/__id__ now uses InteropLibrary#identityHashCode().

Bug fixes:

• Fix #class_exec, #module_exec, #instance_eval, and instance_exec to use activated refinements (#1988, @ssnickolay).
• Fixed missing method error for FFI calls with blocking: true when interrupted.
• Use upgraded default gems when installed (#1956).
• Fixed NameError when requiring an autoload path that does not define the autoload constant (#1905).
• Thread local IO buffers are now allocated using a stack to ensure safe operating if a signal handler uses one during an IO operation.
• Fixed TracePoint thread-safety by storing the state on the Ruby Thread (like MRI) instead of inside the TracePoint instance.
• Make require 'rubygems/package' succeed and define Gem::Deprecate correctly (#2014).
• Fix MBCLEN_CHARFOUND_P error.
• Fix rb_enc_str_new when NULL encoding is given with a constant string.
• Fixed rb_enc_precise_mbclen to handle more inputs.
• The output for --engine.TraceCompilation is now significantly easier to read, by having shorter method names and source names (oracle/graal#2052).
• Fix indentation for squiggly heredoc with single quotes (#1564).
• Only print members which are readable for foreign #inspect (#2027).
• Fixed the return value of the first call to Kernel#srand in a Thread (#2028).
• Fix missing flushing when printing an exception at top-level with a custom backtrace, which caused no output being shown (#1750, #1895).
• Use the mode of the given IO for IO#reopen(IO) which is important for the 3 standard IOs (#2034).
• Fix potential deadlock when running finalizers (#2041).
• Let require 'rubygems/specification' work before require 'rubygems'.

Compatibility:

• Implement UnboundMethod#bind_call.
• Implemented ObjectSpace::WeakMap (#1385, #1958).
• Implemented strtod and ruby_strtod (#2007).
• Fix detection of #find_type in FFI to ignore MakeMakefile#find_type from mkmf (#1896, #2010).
• Implemented rb_uv_to_utf8 (#1998, @skateman).
• Implemented rb_str_cat_cstr.
• Implemented rb_fstring.
• Support #refine for Module (#2021, @ssnickolay).
• Implemented rb_ident_hash_new.
• Improved the compatibility of Symbol.all_symbols (#2022, @chrisseaton).
• Implemented rb_enc_str_buf_cat.
• Implemented rb_int_positive_pow.
• Implemented rb_usascii_str_new_lit.
• Define #getch and #getpass on StringIO when io/console is required.
• Implemented rb_uv_to_utf8 (#1998).
• Single character IDs now behave more like those in MRI to improve C extension compatibility, so rb_funcall(a, '+', b) will now do the same thing as in MRI.
• Removed extra public methods on String.
• Implemented rb_array_sort and rb_array_sort_bang.
• Do not create a finalizers Thread if there are other public languages, which is helpful for polyglot cases (#2035).
• Implemented rb_enc_isalnum and rb_enc_isspace.
• RUBY_REVISION is now the full commit hash used to build TruffleRuby, similar to MRI 2.7+.
• Implemented rb_enc_mbc_to_codepoint.
• Changed the lookup methods to achieve Refinements specification (#2033, @ssnickolay)
• Implemented Digest::Instance#new (#2040).
• Implemented ONIGENC_MBC_CASE_FOLD.
• Fixed Thread#raise to call the exception class' constructor with no arguments when given no message (#2045).
• Fixed refine + super compatibility (#2039, #2048, @ssnickolay)
• Make the top-level exception handler more compatible with MRI (#2047).
• Implemented rb_enc_codelen.
• Implemented Ripper by using the C extension (#1585).

Changes:

• RubyGems gem commands updated to use the --no-document option by default.

Performance:

• Enable lazy translation from the parser AST to the Truffle AST for user code by default. This should improve application startup time (#1992).
• instance variable ... not initialized and similar warnings are now optimized to have no peak performance impact if they are not printed (depends on $VERBOSE).
• Implement integer modular exponentiation using BigInteger#mod_pow (#1999, @skateman)
• Fixed a performance issue when computing many substrings of a given non-leaf String with non-US-ASCII characters.
• Speedup native handle to Ruby object lookup for C extensions.

20.1.0

New features:

• Nightly builds of TruffleRuby are now available, see the README for details (#1483).
• ||= will not compile the right-hand-side if it's only executed once, to match the idiomatic lazy-initialisation use-case (blog post, #1887, @kipply).
• Added --metrics-profile-require option to profile searching, parsing, translating and loading files.
• Added support for captured variables for the Truffle instruments (e.g. Chrome debugger).

Bug fixes:

• Fixed Exception#dup to copy the Exception#backtrace string array.
• Fixed rb_warn and rb_warning when used as statements (#1886, @chrisseaton).
• Fixed NameError.new and NoMethodError.new :receiver argument.
• Correctly handle large numbers of arguments to rb_funcall (#1882).
• Added arity check to Module#{include, prepend}.
• Fix OpenSSL::Digest.{digest,hexdigest,base64digest} to handle algorithm, data arguments (#1889, @bdewater).
• Fixed SystemCallError.new parameter conversion.
• Fixed File#{chmod, umask} argument conversion check.
• Added warning in Hash.[] for non-array elements.
• Fixed File.lchmod to raise NotImplementedError when not available.
• RSTRING_PTR() now always returns a native pointer, resolving two bugs memcpying to (#1822) and from (#1772) Ruby Strings.
• Fixed issue with duping during splat (#1883).
• Fixed Dir#children implementation.
• Fixed SignalException.new error when bad parameter given.
• Added deprecation warning to Kernel#=~.
• Fixed puts for a foreign objects, e.g. puts Polyglot.eval('js', '[]') (#1881).
• Fixed Exception#full_message implementation.
• Updated Kernel.Complex() to handle the exception: false parameter.
• Fixed Kernel#dup to return self for Complex and Rational objects.
• Updated Kernel.Float() to handle the exception: false parameter.
• Fixed String#unpack M format (#1901).
• Fixed error when SystemCallError message contained non-ASCII characters.
• Fixed rb_rescue to allow null rescue methods. (#1909, @kipply).
• Fixed incorrect comparisons between bignums and doubles.
• Prevented some internal uses of Kernel#caller_locations to be overridden by user code (#1934).
• Fixed an issue caused by recursing inlining within Regexp#quote (#1927).
• Updated Kernel.Float() to return given string in error message (#1945).
• Parameters and arity of methods derived from method_missing should now match MRI (#1921).
• Fixed compile error in RB_FLOAT_TYPE_P macro (#1928).
• Fixed Symbol#match to call the block with the MatchData (#1933).
• Fixed Digest::SHA2.hexdigest error with long messages (#1922).
• Fixed Date.parse to dup the coerced string to not modify original (#1946).
• Update Comparable error messages for special constant values (#1941).
• Fixed File.ftype parameter conversion (#1961).
• Fixed Digest::Instance#file to not modify string literals (#1964).
• Make sure that string interpolation returns a String, and not a subclass (#1950).
• alias_method and instance_methods should now work correctly inside a refinement (#1942).
• Fixed Regexp.union parameter conversion (#1963).
• IO#read(n) no longer buffers more than needed, which could cause hanging if detecting readability via a native call such as select(2) (#1951).
• Fixed Random::DEFAULT.seed to be different on boot (#1965, @kipply)
• rb_encoding->name can now be read even if the rb_encoding is stored in native memory.
• Detect and cut off recursion when inspecting a foreign object, substituting an ellipsis instead.
• Fixed feature lookup order to check every $LOAD_PATH path entry for .rb, then every entry for native extension when require is called with no extension.
• Define the _DARWIN_C_SOURCE macro in extension makefiles (#1592).
• Change handling of var args in rb_rescue2 to handle usage in C extensions (#1823).
• Fixed incorrect Encoding::CompatibilityError raised for some interpolated Regexps (#1967).
• Actually unset environment variables with a nil value for Process.spawn instead of setting them to an empty String.
• Core library methods part of the Native Image heap are no longer added in the compilation queue on the first call, but after they reach the thresholds like other methods.
• Fix RbConfig::CONFIG['LIBRUBY_SO'] file extension.
• Fix char, short, unsigned char, unsigned int, and unsigned short types in Fiddle (#1971).
• Fix IO#select to reallocate its buffer if it is interrupted by a signal.
• Fix issue where interpolated string matched # within string as being a variable (#1495).
• Fix File.join to raise error on strings with null bytes.
• Fix initialization of Ruby Thread for foreign thread created in Java.
• Fix registration of default specs in RubyGems (#1987).

Compatibility:

• The C API type VALUE is now defined as unsigned long as on MRI. This enables switch (VALUE) and other expressions which rely on VALUE being an integer type (#1409, #1541, #1675, #1917, #1954).
• Implemented Float#{floor, ceil} with ndigits argument.
• Implemented Thread#fetch.
• Implemented Float#truncate with ndigits argument.
• Made String#{byteslice, slice, slice!} and Symbol#slice compatible with endless ranges.
• Implemented "instance variable not initialized" warning.
• Make Kernel#{caller, caller_locations} and Thread#backtrace_locations compatible with endless ranges.
• Implemented Dir#each_child.
• Implemented Kernel.{chomp, chop} and Kernel#{chomp, chop}.
• Implemented -p and -a, and -l CLI options.
• Convert the argument to File.realpath with #to_path (#1894).
• StringIO#binmode now sets the external encoding to BINARY like MRI (#1898).
• StringIO#inspect should not include the contents of the StringIO (#1898).
• Implemented rb_fd_* functions (#1623).
• Fixed uninitialized variable warnings in core and lib (#1897).
• Make Thread#backtrace support omit, length and range arguments.
• Implemented Range#%.
• Fixed the type of the flags field of rb_data_type_t (#1911).
• Implemented rb_obj_is_proc (#1908, @kipply, @XrXr).
• Implemented C API macro RARRAY_ASET().
• Implemented num2short (#1910, @kipply).
• RSTRING_END() now always returns a native pointer.
• Removed register specifier for rb_mem_clear() (#1924).
• Implemented Thread::Backtrace::Locations#base_label (#1920).
• Implemented rb_mProcess (#1936).
• Implemented rb_gc_latest_gc_info (#1937).
• Implemented RBASIC_CLASS (#1935).
• Yield 2 arguments for Hash#map if the arity of the block is > 1 (#1944).
• Add all Errno constants to match MRI, needed by recent RubyGems.
• Silence ruby_dep warnings since that gem is unmaintained.
• Clarify error message for not implemented Process.daemon (#1962).
• Allow multiple assignments in conditionals (#1513).
• Update NoMethodError#message to match MRI (#1957).
• Make StringIO work with --enable-frozen-string-literal (#1969).
• Support NULL for the status of rb_protect().
• Ensure BigDecimal#inspect does not call BigDecimal#to_s to avoid behaviour change on to_s override (#1960).
• Define all C-API rb_{c,m,e}* constants as C global variables (#1541).
• Raise ArgumentError for Socket.unpack_sockaddr_un if the socket family is incorrect.
• Implemented RTYPEDDATA_*() macros and rb_str_tmp_new() (#1975).
• Implemented rb_set_end_proc (#1959).
• Implemented rb_to_symbol.
• Implemented rb_class_instance_methods, rb_class_public_instance_methods, rb_class_protected_instance_methods, and rb_class_private_instance_methods.
• Implemented rb_tracepoint_new, rb_tracepoint_disable, rb_tracepoint_enable, and rb_tracepoint_enabled_p (#1450).
• Implemented RbConfig::CONFIG['AR'] and RbConfig::CONFIG['STRIP'] (#1973).
• Not yet implemented C API functions are now correctly detected as missing via mkmf's have_func (#1980).
• Accept RUBY_INTERNAL_EVENT_{NEWOBJ,FREEOBJ} events but warn they are not triggered (#1978, #1983).
• IO.copy_stream(in, STDOUT) now writes to STDOUT without buffering like MRI.
• Implemented RbConfig['vendordir'].
• Implemented Enumerator::ArithmeticSequence.
• Support (struct RBasic *)->flags and ->klass from ruby.h (#1891, #1884, #1978).

Changes:

• TRUFFLERUBY_RESILIENT_GEM_HOME has been removed. Unset GEM_HOME and GEM_PATH instead if you need to.
• The deprecated Truffle::System.full_memory_barrier, Truffle::Primitive.logical_processors, and Truffle::AtomicReference have been removed.
• The implicit interface for allowing Ruby objects to behave as polyglot arrays with #size, #[] methods has been removed and replaced with an explicit interface where each method starts with polyglot_*.
• Hash keys are no longer reported as polyglot members.
• All remaining implicit polyglot behaviour for #[] method was replaced with polyglot_* methods.
• Rename dynamic API to match InteropLibrary. All the methods keep the name as it is in InteropLibrary with the following changes: use snake_case, add polyglot_ prefix, drop get and is prefix, append ? on all predicates.
• Split Truffle::Interop.write into .write_array_element and .write_member methods.
• Rename Truffle::Interop.size to .array_size.
• Rename Truffle::Interop.is_boolean? to .boolean?.
• Split Truffle::Interop.read into .read_member and .read_array_element.
• Drop is_ prefix in Truffle::Interop.is_array_element_* predicates.
• Truffle::Interop.hash_keys_as_members has been added to treat a Ruby Hash as a polyglot object with the Hash keys as members.

Performance:

• Optimized RSTRING_PTR() accesses by going to native directly, optimized various core methods, use Mode=latency and tune GC heap size for Bundler. This speeds up bundle install from 84s to 19s for a small Gemfile with 6 gems (#1398).
• Fixed memory footprint issue due to large compilation on Native Image, notably during bundle install (#1893).
• ArrayBuilderNode now uses a new Truffle library for manipulating array stores.
• Ruby objects passed to C extensions are now converted less often to native handles.
• Calling blocking system calls and running C code with unblocking actions has been refactored to remove some optimisation boundaries.
• return expressions are now rewritten as implicit return expressions where control flow allows this to be safely done as a tail optimisation. This can improve interpreter performance by up to 50% in some benchmarks, and can be applied to approximately 80% of return nodes seen in Rails and its dependencies (#1977).
• The old array strategy code has been removed and all remaining nodes converted to the new ArrayStoreLibrary.
• Updated nil to be a global immutable singleton (#1835).

20.0.0

New features:

• Enable and document --coverage option (#1840, @chrisseaton).
• Update the internal LLVM toolchain to LLVM 9 and reduce its download size.
• Updated to Ruby 2.6.5 (#1749).
• Automatically set PKG_CONFIG_PATH as needed for compiling OpenSSL on macOS (#1830).

Bug fixes:

• Fix Tempfile#{size,length} when the IO is not flushed (#1765, @rafaelfranca).
• Dump and load instance variables in subclasses of Exception (#1766, @rafaelfranca).
• Fix Date._iso8601 and Date._rfc3339 when the string is an invalid date (#1773, @rafaelfranca).
• Fail earlier for bad handle unwrapping (#1777, @chrisseaton).
• Match out of range ArgumentError message with MRI (#1774, @rafaelfranca).
• Raise Encoding::CompatibilityError with incompatible encodings on Regexp (#1775, @rafaelfranca).
• Fixed interactions between attributes and instance variables in Struct (#1776, @chrisseaton).
• Coercion fixes for TCPServer.new (#1780, @XrXr).
• Fix Float#<=> not calling coerce when other argument responds to it (#1783, @XrXr).
• Do not warn / crash when requiring a file that sets and trigger autoload on itself (#1779, @XrXr).
• Strip trailing whitespaces when creating a BigDecimal with a String (#1796, @XrXr).
• Default close_others in Process.exec to false like Ruby 2.6 (#1798, @XrXr).
• Don't clone methods when setting method to the same visibility (#1794, @XrXr).
• BigDecimal() deal with large rationals precisely (#1797, @XrXr).
• Make it possible to call instance_exec with rb_block_call (#1802, @XrXr).
• Check for duplicate members in Struct.new (#1803, @XrXr).
• Process::Status#to_i return raw waitpid(2) status (#1800, @XrXr).
• Process#exec: set close-on-exec to false for fd redirection (#1805, @XrXr, @rafaelfranca).
• Building C extensions should now work with frozen string literals (#1786).
• Keep the Truffle working directory in sync with the native working directory.
• Rename to_native to polyglot_to_native to match polyglot_pointer? and polyglot_address methods.
• Fixed missing partial evaluation boundary in Array#{sort,sort!} (#1727).
• Fixed the class of self and the wrapping Module for Kernel#load(path, wrap=true) (#1739).
• Fixed missing polyglot type declaration for RSTRING_PTR to help with native/managed interop.
• Fixed Module#to_s and Module#inspect to not return an extra #<Class: for singleton classes.
• Arrays backed by native storage now allocate the correct amount of memory (#1828).
• Fixed issue in ConditionVariable#wait that could lose a ConditionVariable#signal.
• Do not expose TruffleRuby-specific method Array#swap (#1816).
• Fixed #inspect on broken UTF-8 sequences (#1842, @chrisseaton).
• Truffle::Interop.keys should report methods of String and Symbol (#1817).
• Kernel#sprintf encoding validity has been fixed (#1852, @XrXr).
• Fixed ArrayIndexOutOfBoundsException in File.fnmatch (#1845).
• Make String#concat work with no or multiple arguments (#1519).
• Make Array#concat work with no or multiple arguments (#1519).
• Coerce BigDecimal(arg) using to_str (#1826).
• Fixed NameError#dup, NoMethodError#dup, and SystemCallError#dup to copy internal fields.
• Make Enumerable#chunk work without a block (#1518).
• Fixed issue with SystemCallError.new setting a backtrace too early.
• Fixed BigDecimal#to_s formatting issue (#1711).
• Run END keyword block only once at exit.
• Implement Numeric#clone to return self.
• Fixed Symbol#to_proc to create a Proc with nil source_location (#1663).
• Make GC.start work with keyword arguments.
• Fixed Kernel#clone for nil, true, false, Integer, and Symbol.
• Make top-level methods available in Context#getBindings() (#1838).
• Made Kernel#caller_locations accept a range argument, and return nil when appropriate.
• Made rb_respond_to work with primitives (#1869, @chrisseaton).
• Fixed issue with missing backtrace for rescue $ERROR_INFO (#1660).
• Fixed Struct#hash for keyword_init: true Struct.
• Fixed String#{upcase!,downcase!,swapcase!}(:ascii) for non-ASCII-compatible encodings like UTF-16.
• Fixed String#capitalize! for strings that weren't full ASCII.
• Fixed enumeration issue in ENV.{select, filter}.
• Fixed Complex and Rational should be frozen after initializing.
• Fixed printf should raise error when not enough arguments for positional argument.
• Removed "shadowing outer local variable" warning.
• Fixed parameter conversion to String in ENV methods.
• Fixed deprecation warning when ENV.index is called.
• Fixed issue with ENV.each_key.
• Fixed ENV.replace implementation.
• Fixed ENV.udpate implementation.
• Fixed argument handling in Kernel.printf.
• Fixed character length after conversion to binary from a non-US-ASCII String.
• Fixed issue with installing latest bundler (#1880).
• Fixed type conversion for Numeric#step step parameter.
• Fixed Kernel#Integer conversion.
• Fixed IO.try_convert parameter conversion.
• Fixed linking of always-inline C API functions with -std=gnu90 (#1837, #1879).
• Avoid race conditions during gem install by using a single download thread.
• Do not use gems precompiled for MRI on TruffleRuby (#1837).
• Fixed printing foreign arrays that were also pointers (#1679).
• Fixed nil#=~ to not warn.
• Fixed Enumerable#collect to give user block arity in the block passed to Enumerable#each.

Compatibility:

• Implemented String#start_with?(Regexp) (#1771, @zhublik).
• Various improvements to SignalException and signal handling (#1790, @XrXr).
• Implemented rb_utf8_str_new, rb_utf8_str_new_cstr, rb_utf8_str_new_static (#1788, @chrisseaton).
• Implemented the unit argument of Time.at (#1791, @XrXr).
• Implemented keyword_init: true for Struct.new (#1789, @XrXr).
• Implemented MatchData#dup (#1792, @XrXr).
• Implemented a native storage strategy for Array to allow better C extension compatibility.
• Implemented rb_check_symbol_cstr (#1814).
• Implemented rb_hash_start (#1841, @XrXr).
• JCodings has been updated from 1.0.42 to 1.0.45.
• Joni has been updated from 2.1.25 to 2.1.30.
• Implemented Method#<< and Method#>> (#1821).
• The .bundle file extension is now used for C extensions on macOS (#1819, #1837).
• Implemented Comparable#clamp (#1517).
• Implemented rb_gc_register_mark_object and rb_enc_str_asciionly_p (#1856, @chrisseaton).
• Implemented rb_io_set_nonblock (#1741).
• Include the major kernel version in RUBY_PLATFORM on macOS like MRI (#1860, @eightbitraptor).
• Implemented Enumerator::Chain, Enumerator#+, and Enumerable#chain (#1859, #1858).
• Implemented Thread#backtrace_locations and Exception#backtrace_locations (#1556).
• Implemented rb_module_new, rb_define_class_id, rb_define_module_id, (#1876, @XrXr, @chrisseaton).
• Implemented -n CLI option (#1532).
• Cache the Symbol of method names in call nodes only when needed (#1872).
• Implemented rb_get_alloc_func and related functions (#1874, @XrXr).
• Implemented rb_module_new, rb_define_class_id, rb_define_module_id, (#1876, @chrisseaton).
• Implemented ENV.slice.
• Support for the Darkfish theme for RDoc generation has been added back.
• Implemented Kernel#system exception: true option.
• Implemented Random.bytes.
• Implemented Random.random_number.
• Added the ability to parse endless ranges.
• Made Range#{to_a, step, each, bsearch, step, last, max, min, to_s, ==} compatible with endless ranges.
• Made Array#{[], []=, values_at, fill, slice!} compatible with endless ranges.
• Defined Array#{min, max} methods.

Performance:

• Use a smaller limit for identity-based inline caches to improve warmup by avoiding too many deoptimizations.
• long[] array storage now correctly declare that they accept int values, reducing deoptimisations and promotions to Object[] storage.
• Enable inline caching of Symbol conversion for rb_iv_get and rb_iv_set.
• rb_type information is now cached on classes as a hidden variable to improve performance.
• Change to using thread local buffers for socket calls to reduce allocations.
• Refactor IO.select to reduce copying and optimisation boundaries.
• Refactor various String and Rope nodes to avoid Truffle performance warnings.
• Reading caller frames should now work in more cases without deoptimisation.

19.3.0

New features:

• Compilation of C extensions is now done with an internal LLVM toolchain producing both native code and bitcode. This means more C extensions should compile out of the box and this should resolve most linker-related issues.
• It is no longer necessary to install LLVM for installing C extensions on TruffleRuby.
• It is no longer necessary to install libc++ and libc++abi for installing C++ extensions on TruffleRuby.
• On macOS, it is no longer necessary to install the system headers package (#1417).
• License updated to EPL 2.0/GPL 2.0/LGPL 2.1 like recent JRuby.

Bug fixes:

• rb_undef_method now works for private methods (#1731, @cky).
• Fixed several issues when requiring C extensions concurrently (#1565).
• self.method ||= value with a private method now works correctly (#1673).
• Fixed RegexpError: invalid multibyte escape for binary regexps with a non-binary String (#1433).
• Arrays now report their methods to other languages for interopability (#1768).
• Installing sassc now works due to using the LLVM toolchain (#1753).
• Renamed Truffle::Interop.respond_to? to avoid conflict with Ruby's respond_to? (#1491).
• Warn only if $VERBOSE is true when a magic comment is ignored (#1757, @nirvdrum).
• Make C extensions use the same libssl as the one used for the openssl C extension (#1770).

Compatibility:

• GC.stat can now take an optional argument (#1716, @kirs).
• Kernel#load with wrap has been implemented (#1739).
• Implemented Kernel#spawn with :chdir (#1492).
• Implemented rb_str_drop_bytes, notably used by OpenSSL (#1740, @cky).
• Include executables of default gems, needed for rails new in Rails 6.
• Use compilation flags similar to MRI for C extension compilation.
• Warn for gem update --system as it is not fully supported yet and is often not needed.
• Pass -undefined dynamic_lookup to the linker on macOS like MRI.

Performance:

• Core methods are no longer always cloned, which reduces memory footprint and should improve warmup.
• Inline cache calls to rb_intern() with a constant name in C extensions.
• Improve allocation speed of native handles for C extensions.
• Improve the performance of NIL_P and INT2FIX in C extensions.
• Various fixes to improve Rack performance.
• Optimize String#gsub(String) by not creating a Regexp and using String#index instead.
• Fixed "FrameWithoutBoxing should not be materialized" compilation issue in TryNode.

19.2.0, August 2019

New features:

• Fiddle has been implemented.

Bug fixes:

• Set RbConfig::CONFIG['ruby_version'] to the same value as the TruffleRuby version. This fixes reusing C extensions between different versions of TruffleRuby with Bundler (#1715).
• Fixed Symbol#match returning MatchData (#1706, @zhublik).
• Allow Time#strftime to be called with binary format strings.
• Do not modify the argument passed to IO#write when the encoding does not match (#1714).
• Use the class where the method was defined to check if an UnboundMethod can be used for #define_method (#1710).
• Fixed setting $~ for Enumerable and Enumerator::Lazy's #grep and #grep_v.
• Improved errors when interacting with single-threaded languages (#1709).

Compatibility:

• Added Kernel#then (#1703, @zhublik).
• FFI::Struct#[]= is now supported for inline character arrays.
• blocking: true is now supported for FFI::Library#attach_function.
• Implemented Proc#>> and #<< (#1688).
• Thread.report_on_exception is now true by default like MRI 2.5+.
• BigDecimal compatibility has been generally improved in several ways.

Changes:

• An interop read message sent to a Proc will no longer call the Proc.

Performance:

• Several String methods have been made faster by the usage of vector instructions when searching for a single-byte character in a String.
• Methods needing the caller frame are now better optimized.

19.1.0, June 2019

Ruby is an experimental language in the GraalVM 19.1.0 release

Bug fixes:

• Sharing for thread-safety of objects is now triggered later as intended, e.g., when a second Thread is started.
• Fixed Array#to_h so it doesn't set a default value (#1698).
• Removed extra public methods on IO (#1702).
• Fixed Process.kill(signal, Process.pid) when the signal is trapped as :IGNORE (#1702).
• Fixed Addrinfo.new(String) to reliably find the address family (#1702).
• Fixed argument checks in BasicSocket#setsockopt (#1460).
• Fixed ObjectSpace.trace_object_allocations (#1456).
• Fixed BigDecimal#{clone,dup} so it now just returns the receiver, per Ruby 2.5+ semantics (#1680).
• Fixed creating BigDecimal instances from non-finite Float values (#1685).
• Fixed BigDecimal#inspect output for non-finite values (e.g, NaN or -Infinity) (#1683).
• Fixed BigDecimal#hash to return the same value for two BigDecimal objects that are equal (#1656).
• Added missing BigDecimal constant definitions (#1684).
• Implemented rb_eval_string_protect.
• Fixed rb_get_kwargs to correctly handle optional and rest arguments.
• Calling Kernel#raise with a raised exception will no longer set the cause of the exception to itself (#1682).
• Return a FFI::Function correctly for functions returning a callback.
• Convert to intuitive Ruby exceptions when INVOKE fails (#1690).
• Implemented FFI::Pointer#clear (#1687).
• Procs will now yield to the block in their declaration context even when called with a block argument (#1657).
• Fixed problems with calling POSIX methods if Symbol#[] is redefined (#1665).
• Fixed sharing of Array and Hash elements for thread-safety of objects (#1601).
• Fixed concurrent modifications of Gem::Specification::LOAD_CACHE (#1601).
• Fix TCPServer#accept to set #do_not_reverse_lookup correctly on the created TCPSocket.

Compatibility:

• Exceptions from coerce are no longer rescued, like MRI.
• Implemented Integer#{allbits?,anybits?,nobits?}.
• Integer#{ceil,floor,truncate} now accept a precision and Integer#round accepts a rounding mode.
• Added missing Enumerable#filter and Enumerator::Lazy#filter aliases to the respective select method (#1610).
• Implemented more Ripper methods as no-ops (#1694, @Mogztter).
• Implemented rb_enc_sprintf (#1702).
• Implemented ENV#{filter,filter!} aliases for select and select!.
• Non-blocking StringIO and Socket APIs now support exception: false like MRI (#1702).
• Increased compatibility of BigDecimal.
• String#-@ now performs string deduplication (#1608).
• Hash#merge now preserves the key order from the original hash for merged values (#1650).
• Coerce values given to FFI::Pointer methods.
• FrozenError is now defined and is used for can't modify frozen object exceptions.
• StringIO is now available by default like in MRI, because it is required by RubyGems.

Changes:

• Interactive sources (like the GraalVM polyglot shell) now all share the same binding (#1695).
• Hash code calculation has been improved to reduce hash collisions for Hash and other cases.

Performance:

• eval(code, binding) for a fixed code containing blocks is now much faster. This improves the performance of rendering ERB templates containing loops.
• rb_str_cat is faster due to the C string now being concatenated without first being converted to a Ruby string or having its encoding checked. As a side effect the behaviour of rb_str_cat should now more closely match that of MRI.

19.0.0, May 2019

Ruby is an experimental language in the GraalVM 19.0.0 release

Bug fixes:

• The debugger now sees global variables as the global scope.
• Temporary variables are no longer visible in the debugger.
• Setting breakpoints on some lines has been fixed.
• The OpenSSL C extension is now always recompiled, fixing various bugs when using the extension (e.g., when using Bundler in TravisCI) (#1676, #1627, #1632).
• Initialize $0 when not run from the 'ruby' launcher, which is needed to require gems (#1653).

Compatibility:

• do...end blocks can now have rescue/else/ensure clauses like MRI (#1618).

Changes:

• TruffleRuby.sulong? has been replaced by TruffleRuby.cexts?, and TruffleRuby.graal? has been replaced by TruffleRuby.jit?. The old methods will continue to work for now, but will produce warnings, and will be removed at a future release.

1.0 RC 16, 19 April 2019

Bug fixes:

• Fixed Hash#merge with no arguments to return a new copy of the receiver (#1645).
• Fixed yield with a splat and keyword arguments (#1613).
• Fixed rb_scan_args to correctly handle kwargs in combination with optional args.
• Many fixes for FFI::Pointer to be more compatible with the ffi gem.

New features:

• Rounding modes have been implemented or improved for Float, Rational, BigDecimal (#1509).
• Support Homebrew installed in other prefixes than /usr/local (#1583).
• Added a pure-Ruby implementation of FFI which passes almost all Ruby FFI specs (#1529, #1524).

Changes:

• Support for the Darkfish theme for RDoc generation has been removed.

Compatibility:

• The KeyError raised from ENV#fetch and Hash#fetch now matches MRI's message formatting (#1633).
• Add the missing key and receiver values to KeyError raised from ENV#fetch.
• String#unicode_normalize has been moved to the core library like in MRI.
• StringScanner will now match a regexp beginning with ^ even when not scanning from the start of the string.
• Module#define_method is now public like in MRI.
• Kernel#warn now supports the uplevel: keyword argument.

1.0 RC 15, 5 April 2019

Bug fixes:

• Improved compatibility with MRI's Float#to_s formatting (#1626).
• Fixed String#inspect when the string uses a non-UTF-8 ASCII-compatible encoding and has non-ASCII characters.
• Fixed puts for strings with non-ASCII-compatible encodings.
• rb_protect now returns Qnil when an error occurs.
• Fixed a race condition when using the interpolate-once (/o) modifier in regular expressions.
• Calling StringIO#close multiple times no longer raises an exception (#1640).
• Fixed a bug in include file resolution when compiling C extensions.

New features:

• Process.clock_getres has been implemented.

Changes:

• debug, profile, profiler, which were already marked as unsupported, have been removed.
• Our experimental JRuby-compatible Java interop has been removed - use Polyglot and Java instead.
• The Trufle handle patches applied to psych C extension have now been removed.
• The rb_tr_handle_* functions have been removed as they are no longer used in any C extension patches.
• Underscores and dots in options have become hyphens, so --exceptions.print_uncaught_java is now --exceptions-print-uncaught-java, for example.
• The rb_tr_handle_* functions have been removed as they are no longer used in any C extension patches.

Bug fixes:

• autoload :C, "path"; require "path" now correctly triggers the autoload.
• Fixed UDPSocket#bind to specify family and socktype when resolving address.
• The shell standard library can now be require-d.
• Fixed a bug where for could result in a NullPointerException when trying to assign the iteration variable.
• Existing global variables can now become aliases of other global variables (#1590).

Compatibility:

• ERB now uses StringScanner and not the fallback, like on MRI. As a result strscan is required by require 'erb' (#1615).
• Yield different number of arguments for Hash#each and Hash#each_pair based on the block arity like MRI (#1629).
• Add support for the base keyword argument to Dir.{[], glob}.

1.0 RC 14, 18 March 2019

Updated to Ruby 2.6.2.

Bug fixes:

• Implement rb_io_wait_writable (#1586).
• Fixed error when using arrows keys first within irb or pry (#1478, #1486).
• Coerce the right hand side for all BigDecimal operations (#1598).
• Combining multiple ** arguments containing duplicate keys produced an incorrect hash. This has now been fixed (#1469).
• IO#read_nonblock now returns the passed buffer object, if one is supplied.
• Worked out autoloading issue (#1614).

New features:

• Implemented String#delete_prefix, #delete_suffix, and related methods.
• Implemented Dir.children and Dir#children.
• Implemented Integer#sqrt.

Changes:

• -Xoptions has been removed - use --help:languages instead.
• -Xlog= has been removed - use --log.level= instead.
• -J has been removed - use --vm. instead.
• -J-cp lib.jar and so on have removed - use --vm.cp=lib.jar or --vm.classpath=lib.jar instead.
• --jvm. and --native. have been deprecated, use --vm. instead to pass VM options.
• -Xoption=value has been removed - use --option=value instead.
• The -X option now works as in MRI.
• --help:debug is now --help:internal.
• ripper is still not implemented, but the module now exists and has some methods that are implemented as no-ops.

1.0 RC 13, 5 March 2019

Note that as TruffleRuby RC 13 is built on Ruby 2.4.4 it is still vulnerable to CVE-2018-16395. This will be fixed in the next release.

New features:

• Host interop with Java now works on SubstrateVM too.

Bug fixes:

• Fixed Enumerator::Lazy which wrongly rescued StandardError (#1557).
• Fixed several problems with Numeric#step related to default arguments, infinite sequences, and bad argument types (#1520).
• Fixed incorrect raising of ArgumentError with Range#step when at least one component of the Range is Float::INFINITY (#1503).
• Fixed the wrong encoding being associated with certain forms of heredoc strings (#1563).
• Call #coerce on right hand operator if BigDecimal is the left hand operator (#1533, @Quintasan).
• Fixed return type of division of Integer.MIN_VALUE and Long.MIN_VALUE by -1 (#1581).
• Exception#cause is now correctly set for internal exceptions (#1560).
• rb_num2ull is now implemented as well as being declared in the ruby.h header (#1573).
• rb_sym_to_s is now implemented (#1575).
• R_TYPE_P now returns the type number for a wider set of Ruby objects (#1574).
• rb_fix2str has now been implemented.
• rb_protect will now work even if NilClass#== has been redefined.
• BigDecimal has been moved out of the Truffle module to match MRI.
• StringIO#puts now correctly handles to_s methods which do not return strings (#1577).
• Array#each now behaves like MRI when the array is modified (#1580).
• Clarified that $SAFE can never be set to a non-zero value.
• Fix compatibility with RubyGems 3 (#1558).
• Kernel#respond_to? now returns false if a method is protected and the include_all argument is false (#1568).

Changes:

• TRUFFLERUBY_CEXT_ENABLED is no longer supported and C extensions are now always built, regardless of the value of this environment variable.
• Getting a substring of a string created by a C extension now uses less memory as only the requested portion will be copied to a managed string.
• -Xoptions has been deprecated and will be removed - use --help:languages instead.
• -Xlog= has been deprecated and will be removed - use --log.level= instead.
• -J has been deprecated and will be removed - use --jvm. instead.
• -J-cp lib.jar and so on have been deprecated and will be removed - use --jvm.cp=lib.jar or --jvm.classpath=lib.jar instead.
• -J-cmd, --jvm.cmd, JAVA_HOME, JAVACMD, and JAVA_OPTS do not work in any released configuration of TruffleRuby, so have been removed.
• -Xoption=value has been deprecated and will be removed - use --option=value instead.
• TracePoint now raises an ArgumentError for unsupported events.
• TracePoint.trace and TracePoint#inspect have been implemented.

Compatibility:

• Improved the exception when an -S file isn't found.
• Removed the message from exceptions raised by bare raise to better match MRI (#1487).
• TracePoint now handles the :class event.

Performance:

• Sped up String handling in native extensions, quite substantially in some cases, by reducing conversions between native and managed strings and allowing for mutable metadata in native strings.

1.0 RC 12, 4 February 2019

Bug fixes:

• Fixed a bug with String#lines and similar methods with multibyte characters (#1543).
• Fixed an issue with String#{encode,encode!} double-processing strings using XML conversion options and a new destination encoding (#1545).
• Fixed a bug where a raised cloned exception would be caught as the original exception (#1542).
• Fixed a bug with StringScanner and patterns starting with ^ (#1544).
• Fixed Enumerable::Lazy#uniq with infinite streams (#1516).

Compatibility:

• Change to a new system for handling Ruby objects in C extensions which greatly increases compatibility with MRI.
• Implemented BigDecimal#to_r (#1521).
• Symbol#to_proc now returns -1 like on MRI (#1462).

1.0 RC 11, 15 January 2019

New features:

• macOS clocks CLOCK_MONOTONIC_RAW, _MONOTONIC_RAW_APPROX, _UPTIME_RAW, _UPTIME_RAW_APPROX, and _PROCESS_CPUTIME_ID have been implemented (#1480).
• TruffleRuby now automatically detects native access and threading permissions from the Context API, and can run code with no permissions given (Context.create()).

Bug fixes:

• FFI::Pointer now does the correct range checks for signed and unsigned values.
• Allow signal 0 to be used with Process.kill (#1474).
• IO#dup now properly sets the new IO instance to be close-on-exec.
• IO#reopen now properly resets the receiver to be close-on-exec.
• StringIO#set_encoding no longer raises an exception if the underlying String is frozen (#1473).
• Fix handling of Symbol encodings in Marshal#dump and Marshal#load (#1530).

Compatibility:

• Implemented Dir.each_child.
• Adding missing support for the close_others option to exec and spawn.
• Implemented the missing MatchData#named_captures method (#1512).

Changes:

• Process::CLOCK_ constants have been given the same value as in standard Ruby.

Performance:

• Sped up accesses to native memory through FFI::Pointer.
• All core files now make use of frozen String literals, reducing the number of String allocations for core methods.
• New -Xclone.disable option to disable all manual cloning.

1.0 RC 10, 5 December 2018

New features:

• The nkf and kconv standard libraries were added (#1439).
• Mutex and ConditionVariable have a new fast path for acquiring locks that are unlocked.
• Queue and SizedQueue, #close and #closed?, have been implemented.
• Kernel#clone(freeze) has been implemented (#1454).
• Warning.warn has been implemented (#1470).
• Thread.report_on_exception has been implemented (#1476).
• The emulation symbols for Process.clock_gettime have been implemented.

Bug fixes:

• Added rb_eEncodingError for C extensions (#1437).
• Fixed race condition when creating threads (#1445).
• Handle exception: false for IO#write_nonblock (#1457, @ioquatix).
• Fixed Socket#connect_nonblock for the EISCONN case (#1465, @ioquatix).
• File.expand_path now raises an exception for a non-absolute user-home.
• ArgumentError messages now better match MRI (#1467).
• Added support for :float_millisecond, :millisecond, and :second time units to Process.clock_gettime (#1468).
• Fixed backtrace of re-raised exceptions (#1459).
• Updated an exception message in Psych related to loading a non-existing class so that it now matches MRI.
• Fixed a JRuby-style Java interop compatibility issue seen in test-unit.
• Fixed problem with calling warn if $stderr has been reassigned.
• Fixed definition of RB_ENCODING_GET_INLINED (#1440).

Changes:

• Timezone messages are now logged at CONFIG level, use -Xlog=CONFIG to debug if the timezone is incorrectly shown as UTC.

1.0 RC 9, 5 November 2018

Security:

• CVE-2018-16396, tainted flags are not propagated in Array#pack and String#unpack with some directives has been mitigated by adding additional taint operations.

New features:

• LLVM for Oracle Linux 7 can now be installed without building from source.

Bug fixes:

• Times can now be created with UTC offsets in +/-HH:MM:SS format.
• Proc#to_s now has ASCII-8BIT as its encoding instead of the incorrect UTF-8.
• String#% now has the correct encoding for UTF-8 and US-ASCII format strings, instead of the incorrect ASCII-8BIT.
• Updated BigDecimal#to_s to use e instead of E for exponent notation.
• Fixed BigDecimal#to_s to allow f as a format flag to indicate conventional floating point notation. Previously only F was allowed.

Changes:

• The supported version of LLVM for Oracle Linux has been updated from 3.8 to 4.0.
• mysql2 is now patched to avoid a bug in passing NULL to rb_scan_args, and now passes the majority of its test suite.
• The post-install script now automatically detects if recompiling the OpenSSL C extension is needed. The post-install script should always be run in TravisCI as well, see doc/user/standalone-distribution.md.
• Detect when the system libssl is incompatible more accurately and add instructions on how to recompile the extension.

1.0 RC 8, 19 October 2018

New features:

• Java.synchronized(object) { } and TruffleRuby.synchronized(object) { } methods have been added.
• Added a TruffleRuby::AtomicReference class.
• Ubuntu 18.04 LTS is now supported.
• macOS 10.14 (Mojave) is now supported.

Changes:

• Random seeds now use Java's NativePRNGNonBlocking.
• The supported version of Fedora is now 28, upgraded from 25.
• The FFI gem has been updated from 1.9.18 to 1.9.25.
• JCodings has been updated from 1.0.30 to 1.0.40.
• Joni has been updated from 2.1.16 to 2.1.25.

Performance:

• Performance of setting the last exception on a thread has now been improved.

1.0 RC 7, 3 October 2018

New features:

• Useful inspect strings have been added for more foreign objects.
• The C extension API now defines a preprocessor macro TRUFFLERUBY.
• Added the rbconfig/sizeof native extension for better MRI compatibility.
• Support for pg 1.1. The extension now compiles successfully, but may still have issues with some datatypes.

Bug fixes:

• readline can now be interrupted by the interrupt signal (Ctrl+C). This fixes Ctrl+C to work in IRB.
• Better compatibility with C extensions due to a new "managed struct" type.
• Fixed compilation warnings which produced confusing messages for end users (#1422).
• Improved compatibility with Truffle polyglot STDIO.
• Fixed version check preventing TruffleRuby from working with Bundler 2.0 and later (#1413).
• Fixed problem with Kernel.public_send not tracking its caller properly (#1425).
• rb_thread_call_without_gvl() no longer holds the C-extensions lock.
• Fixed caller_locations when called inside method_added.
• Fixed mon_initialize when called inside initialize_copy (#1428).
• Mutex correctly raises a TypeError when trying to serialize with Marshal.dump.

Performance:

• Reduced memory footprint for private/internal AST nodes.
• Increased the number of cases in which string equality checks will become compile-time constants.
• Major performance improvement for exceptional paths where the rescue body does not access the exception object (e.g., x.size rescue 0).

Changes:

• Many clean-ups to our internal patching mechanism used to make some native extensions run on TruffleRuby.
• Removed obsoleted patches for Bundler compatibility now that Bundler 1.16.5 has built-in support for TruffleRuby.
• Reimplemented exceptions and other APIs that can return a backtrace to use Truffle's lazy stacktraces API.

1.0 RC 6, 3 September 2018

New features:

• Polyglot.export can now be used with primitives, and will now convert strings to Java, and .import will convert them from Java.
• Implemented --encoding, --external-encoding, --internal-encoding.
• rb_object_tainted and similar C functions have been implemented.
• rb_struct_define_under has been implemented.
• RbConfig::CONFIG['sysconfdir'] has been implemented.
• Etc has been implemented (#1403).
• The -Xcexts=false option disables C extensions.
• Instrumentation such as the CPUSampler reports methods in a clearer way like Foo#bar, Gem::Specification.each_spec, block in Foo#bar instead of just bar, each_spec, block in bar (which is what MRI displays in backtraces).
• TruffleRuby is now usable as a JSR 223 (javax.script) language.
• A migration guide from JRuby (doc/user/jruby-migration.md) is now included.
• kind_of? works as an alias for is_a? on foreign objects.
• Boxed foreign strings unbox on to_s, to_str, and inspect.

Bug fixes:

• Fix false-positive circular warning during autoload.
• Fix Truffle::AtomicReference for concurrent-ruby.
• Correctly look up llvm-link along clang and opt so it is no longer needed to add LLVM to PATH on macOS for Homebrew and MacPorts.
• Fix alias to work when in a refinement module (#1394).
• Array#reject! no longer truncates the array if the block raises an exception for an element.
• WeakRef now has the same inheritance and methods as MRI's version.
• Support -Wl linker argument for C extensions. Fixes compilation ofmysql2 and pg.
• Using Module#const_get with a scoped argument will now correctly autoload the constant if needed.
• Loaded files are read as raw bytes, rather than as a UTF-8 string and then converted back into bytes.
• Return 'DEFAULT' for Signal.trap(:INT) {}. Avoids a backtrace when quitting a Sinatra server with Ctrl+C.
• Support Signal.trap('PIPE', 'SYSTEM_DEFAULT'), used by the gem rouge (#1411).
• Fix arity checks and handling of arity -2 for rb_define_method().
• Setting $SAFE to a negative value now raises a SecurityError.
• The offset of DATA is now correct in the presence of heredocs.
• Fix double-loading of the json gem, which led to duplicate constant definition warnings.
• Fix definition of RB_NIL_P to be early enough. Fixes compilation of msgpack.
• Fix compilation of megamorphic interop calls.
• Kernel#singleton_methods now correctly ignores prepended modules of non-singleton classes. Fixes loading sass when activesupport is loaded.
• Object identity numbers should never be negative.

Performance:

• Optimize keyword rest arguments (def foo(**kwrest)).
• Optimize rejected (non-Symbol keys) keyword arguments.
• Source SecureRandom.random_bytes from /dev/urandom rather than OpenSSL.
• C extension bitcode is no longer encoded as Base64 to pass it to Sulong.
• Faster String#== using vectorization.

Changes:

• Clarified that all sources that come in from the Polyglot API eval method will be treated as UTF-8, and cannot be re-interpreted as another encoding using a magic comment.
• The -Xembedded option can now be set set on the launcher command line.
• The -Xplatform.native=false option can now load the core library, by enabling -Xpolyglot.stdio.
• $SAFE and Thread#safe_level now cannot be set to 1 - raising an error rather than warning as before. -Xsafe allows it to be set, but there are still no checks.
• Foreign objects are now printed as #<Foreign:system-identity-hash-code>, except for foreign arrays which are now printed as #<Foreign [elements...]>.
• Foreign objects to_s now calls inspect rather than Java's toString.
• The embedded configuration (-Xembedded) now warns about features which may not work well embedded, such as signals.
• The -Xsync.stdio option has been removed - use standard Ruby STDOUT.sync = true in your program instead.

1.0 RC 5, 3 August 2018

New features:

• It is no longer needed to add LLVM (/usr/local/opt/llvm@4/bin) to PATH on macOS.
• Improve error message when LLVM, clang or opt is missing.
• Automatically find LLVM and libssl with MacPorts on macOS (#1386).
• --log.ruby.level= can be used to set the log level from any launcher.
• Add documentation about installing with Ruby managers/installers and how to run TruffleRuby in CI such as TravisCI (#1062, #1070).
• String#unpack1 has been implemented.

Bug fixes:

• Allow any name for constants with rb_const_get()/rb_const_set() (#1380).
• Fix defined? with an autoload constant to not raise but return nil if the autoload fails (#1377).
• Binary Ruby Strings can now only be converted to Java Strings if they only contain US-ASCII characters. Otherwise, they would produce garbled Java Strings (#1376).
• #autoload now correctly calls main.require(path) dynamically.
• Hide internal file from user-level backtraces (#1375).
• Show caller information in warnings from the core library (#1375).
• #require and #require_relative should keep symlinks in $" and __FILE__ (#1383).
• Random seeds now always come directly from /dev/urandom for MRI compatibility.
• SIGINFO, SIGEMT and SIGPWR are now defined (#1382).
• Optional and operator assignment expressions now return the value assigned, not the value returned by an assignment method (#1391).
• WeakRef.new will now return the correct type of object, even if WeakRef is subclassed (#1391).
• Resolving constants in prepended modules failed, this has now been fixed (#1391).
• Send and Symbol#to_proc now take account of refinements at their call sites (#1391).
• Better warning when the timezone cannot be found on WSL (#1393).
• Allow special encoding names in String#force_encoding and raise an exception on bad encoding names (#1397).
• Fix Socket.getifaddrs which would wrongly return an empty array (#1375).
• Binding now remembers the file and line at which it was created for #eval. This is notably used by pry's binding.pry.
• Resolve symlinks in GEM_HOME and GEM_PATH to avoid related problems (#1383).
• Refactor and fix #autoload so other threads see the constant defined while the autoload is in progress (#1332).
• Strings backed by NativeRopes now make a copy of the rope when duped.
• String#unpack now taints return strings if the format was tainted, and now does not taint the return array if the format was tainted.
• Lots of fixes to Array#pack and String#unpack tainting, and a better implementation of P and p.
• Array literals could evaluate an element twice under some circumstances. This has now been fixed.

Performance:

• Optimize required and optional keyword arguments.
• rb_enc_to_index is now faster by eliminating an expensive look-up.

Changes:

• -Xlog= now needs log level names to be upper case.
• -Dtruffleruby.log and TRUFFLERUBY_LOG have been removed - use -Dpolyglot.log.ruby.level.
• The log format, handlers, etc are now managed by the Truffle logging system.
• The custom log levels PERFORMANCE and PATCH have been removed.

1.0 RC 4, 18 July 2018

TruffleRuby was not updated in RC 4

1.0 RC 3, 2 July 2018

New features:

• is_a? can be called on foreign objects.

Bug fixes:

• It is no longer needed to have ruby in $PATH to run the post-install hook.
• Qnil/Qtrue/Qfalse/Qundef can now be used as initial value for global variables in C extensions.
• Fixed error message when the runtime libssl has no SSLv2 support (on Ubuntu 16.04 for instance).
• RbConfig::CONFIG['extra_bindirs'] is now a String as other RbConfig values.
• SIGPIPE is correctly caught on SubstrateVM, and the corresponding write() raises Errno::EPIPE when the read end of a pipe or socket is closed.
• Use the magic encoding comment for determining the source encoding when using eval().
• Fixed a couple bugs where the encoding was not preserved correctly.

Performance:

• Faster stat()-related calls, by returning the relevant field directly and avoiding extra allocations.
• rb_str_new()/rb_str_new_cstr() are much faster by avoiding extra copying and allocations.
• String#{sub,sub!} are faster in the common case of an empty replacement string.
• Eliminated many unnecessary memory copy operations when reading from IO with a delimiter (e.g., IO#each), leading to overall improved IO reading for common use cases such as iterating through lines in a File.
• Use the byte[] of the given Ruby String when calling eval() directly for parsing.

1.0 RC 2, 6 June 2018

New features:

• We are now compatible with Ruby 2.4.4.
• object.class on a Java Class object will give you an object on which you can call instance methods, rather than static methods which is what you get by default.
• The log level can now also be set with -Dtruffleruby.log=info or TRUFFLERUBY_LOG=info.
• -Xbacktraces.raise will print Ruby backtraces whenever an exception is raised.
• Java.import name imports Java classes as top-level constants.
• Coercion of foreign numbers to Ruby numbers now works.
• to_s works on all foreign objects and calls the Java toString.
• to_str will try to UNBOX and then re-try to_str, in order to provoke the unboxing of foreign strings.

Changes:

• The version string now mentions if you're running GraalVM Community Edition (GraalVM CE) or GraalVM Enterprise Edition (GraalVM EE).
• The inline JavaScript functionality -Xinline_js has been removed.
• Line numbers < 0, in the various eval methods, are now warned about, because we don't support these at all. Line numbers > 1 are warned about (at the fine level) but they are shimmed by adding blank lines in front to get to the correct offset. Line numbers starting at 0 are also warned about at the fine level and set to 1 instead.
• The erb standard library has been patched to stop using a -1 line number.
• -Xbacktraces.interleave_java now includes all the trailing Java frames.
• Objects with a [] method, except for Hash, now do not return anything for KEYS, to avoid the impression that you could READ them. KEYINFO also returns nothing for these objects, except for Array where it returns information on indices.
• String now returns false for HAS_KEYS.
• The supported additional functionality module has been renamed from Truffle to TruffleRuby. Anything not documented in doc/user/truffleruby-additions.md should not be used.
• Imprecise wrong gem directory detection was replaced. TruffleRuby newly marks its gem directories with a marker file, and warns if you try to use TruffleRuby with a gem directory which is lacking the marker.

Bug fixes:

• TruffleRuby on SubstrateVM now correctly determines the system timezone.
• Kernel#require_relative now coerces the feature argument to a path and canonicalizes it before requiring, and it now uses the current directory as the directory for a synthetic file name from #instance_eval.

1.0 RC 1, 17 April 2018

New features:

• The Ruby version has been updated to version 2.3.7.

Security:

• CVE-2018-6914, CVE-2018-8779, CVE-2018-8780, CVE-2018-8777, CVE-2017-17742 and CVE-2018-8778 have been mitigated.

Changes:

• RubyTruffleError has been removed and uses replaced with standard exceptions.
• C++ libraries like libc++ are now not needed if you don't run C++ extensions. libc++abi is now never needed. Documentation updated to make it more clear what the minimum requirements for pure Ruby, C extensions, and C++ extensions separately.
• C extensions are now built by default - TRUFFLERUBY_CEXT_ENABLED is assumed true unless set to false.
• The KEYS interop message now returns an array of Java strings, rather than Ruby strings. KEYS on an array no longer returns indices.
• HAS_SIZE now only returns true for Array.
• A method call on a foreign object that looks like an operator (the method name does not begin with a letter) will call IS_BOXED on the object and based on that will possibly UNBOX and convert to Ruby.
• Now using the native version of Psych.
• The supported version of LLVM on Oracle Linux has been dropped to 3.8.
• The supported version of Fedora has been dropped to 25, and the supported version of LLVM to 3.8, due to LLVM incompatibilities. The instructions for installing libssl have changed to match.

0.33, April 2018

New features:

• The Ruby version has been updated to version 2.3.6.
• Context pre-initialization with TruffleRuby --native, which significantly improves startup time and loads the did_you_mean gem ahead of time.
• The default VM is changed to SubstrateVM, where the startup is significantly better. Use --jvm option for full JVM VM.
• The Truffle::Interop module has been replaced with a new Polyglot module which is designed to use more idiomatic Ruby syntax rather than explicit methods. A new document describes polyglot programming at a higher level.
• The REMOVABLE, MODIFIABLE and INSERTABLE Truffle interop key info flags have been implemented.
• equal? on foreign objects will check if the underlying objects are equal if both are Java interop objects.
• delete on foreign objects will send REMOVE, size will send GET_SIZE, and keys will send KEYS. respond_to?(:size) will send HAS_SIZE, respond_to?(:keys) will send HAS_KEYS.
• Added a new Java-interop API similar to the one in the Nashorn JavaScript implementation, as also implemented by Graal.js. The Java.type method returns a Java class object on which you can use normal interop methods. Needs the --jvm flag to be used.
• Supported and tested versions of LLVM for different platforms have been more precisely documented.

Changes:

• Interop semantics of INVOKE, READ, WRITE, KEYS and KEY_INFO have changed significantly, so that INVOKE maps to Ruby method calls, READ calls [] or returns (bound) Method objects, and WRITE calls []=.

Performance:

• Dir.glob is much faster and more memory efficient in cases that can reduce to direct filename lookups.
• SecureRandom now defers loading OpenSSL until it's needed, reducing time to load SecureRandom.
• Array#dup and Array#shift have been made constant-time operations by sharing the array storage and keeping a starting index.

Bug fixes:

• Interop key-info works with non-string-like names.

Internal changes:

• Changes to the lexer and translator to reduce regular expression calls.
• Some JRuby sources have been updated to 9.1.13.0.

0.32, March 2018

New features:

• A new embedded configuration is used when TruffleRuby is used from another language or application. This disables features like signals which may conflict with the embedding application, and threads which may conflict with other languages, and enables features such as the use of polyglot IO streams.

Performance:

• Conversion of ASCII-only Ruby strings to Java strings is now faster.
• Several operations on multi-byte character strings are now faster.
• Native I/O reads are about 22% faster.

Bug fixes:

• The launcher accepts --native and similar options in the TRUFFLERUBYOPT environment variable.

Internal changes:

• The launcher is now part of the TruffleRuby repository, rather than part of the GraalVM repository.
• ArrayBuilderNode now uses ArrayStrategies and ArrayMirrors to remove direct knowledge of array storage.
• RStringPtr and RStringPtrEnd now report as pointers for interop purposes, fixing several issues with char * usage in C extensions.