August 2025 - ruby-core - ml.ruby-lang.org

[ruby-core:122899] [Ruby Bug#21528] SyntaxError#message may have broken encoding with multibyte source under Prism
by alpaca-tc (Hiroyuki Ishii) 02 Aug '25

02 Aug '25

Issue #21528 has been reported by alpaca-tc (Hiroyuki Ishii). ---------------------------------------- Bug #21528: SyntaxError#message may have broken encoding with multibyte source under Prism https://bugs.ruby-lang.org/issues/21528 * Author: alpaca-tc (Hiroyuki Ishii) * Status: Open * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- Since the introduction of Prism, when parsing Ruby source code that contains multibyte characters, SyntaxError#message can sometimes have invalid encoding. Here is a reproducible example: ``` begin RubyVM::InstructionSequence.compile(<<~CODE, nil, nil, 1) if a # 0000000000000ああああああ # CODE rescue SyntaxError => e $e = e puts e.message # string contains a multibyte character that is cut off mid-byte. \xE3 # <compiled>:3: syntax errors found # 1 | if a # > 2 | # 0000000000000あああああ\xE3 ... # | ^ expected an `end` to close the conditional clause # > 3 | # # | ^ unexpected end-of-input, assuming it is closing the parent top level context puts e.message.valid_encoding? #=> expected true, but got false end ``` This appears to be caused by a truncation process in prism's error message generating that does not consider multibyte character boundaries. See: The truncation logic around [prism_compile.c L10696-L10709](https://github.com/ruby/ruby//blob/30a20bc166bc37acd7dcb3788… I'm not sure how to correctly fix it due to lack of knowledge about safe byte truncation. I discovered this issue through irb, which attempts to display source code even when it contains syntax errors. Because irb uses `SyntaxError#message`, it raised an `ArgumentError: invalid byte sequence in UTF-8`. See: https://github.com/ruby/irb/blob/f60dfa8549f746f69e9a6d160604a7a4974ffac1/l… If this is considered an irb issue, I already have a patch for IRB that handles it. -- https://bugs.ruby-lang.org/

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[ruby-core:122898] [Ruby Feature#21527] Proposal: Math.log1p and Math.expm1
by mame (Yusuke Endoh) 02 Aug '25

02 Aug '25

Issue #21527 has been reported by mame (Yusuke Endoh). ---------------------------------------- Feature #21527: Proposal: Math.log1p and Math.expm1 https://bugs.ruby-lang.org/issues/21527 * Author: mame (Yusuke Endoh) * Status: Open ---------------------------------------- Let's add `Math.log1p` and `Math.expm1`. * `Math.log1p(x)`: Computes `Math.log(x + 1)` * `Math.expm1(x)`: Computes `Math.exp(x) - 1` These methods are often more accurate than the straightforward computation, especially when `x` is close to zero. ``` # The current approach loses precision p Math.log(1 + 1.0e-16) #=> 0.0 p Math.exp(1.0e-16) - 1 #=> 0.0 # The proposed methods return the accurate result p Math.log1p(1.0e-16) #=> 1.0e-16 p Math.expm1(1.0e-16) #=> 1.0e-16 ``` Note that they are very standard; the C99 even defines `log1p()` and `expm1()`. Other major programming languages (Python, JavaScript, Java, Go, Rust, etc.) also provide them. PR: https://github.com/ruby/ruby/pull/14087 -- https://bugs.ruby-lang.org/

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[ruby-core:122897] [Ruby Feature#21526] cryptocurrency & cybersecurity
by umershafique89＠gmail.com (Muhammad umar) 01 Aug '25

01 Aug '25

Issue #21526 has been reported by umershafique89(a)gmail.com (Muhammad umar). ---------------------------------------- Feature #21526: cryptocurrency & cybersecurity https://bugs.ruby-lang.org/issues/21526 * Author: umershafique89(a)gmail.com (Muhammad umar) * Status: Open ---------------------------------------- -- https://bugs.ruby-lang.org/

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[ruby-core:120873] [Ruby master Bug#21111] RbConfig::CONFIG['CXX'] quietly set to "false" when Ruby cannot build C++ programs
by stanhu (Stan Hu) 01 Aug '25

01 Aug '25

Issue #21111 has been reported by stanhu (Stan Hu). ---------------------------------------- Bug #21111: RbConfig::CONFIG['CXX'] quietly set to "false" when Ruby cannot build C++ programs https://bugs.ruby-lang.org/issues/21111 * Author: stanhu (Stan Hu) * Status: Open * ruby -v: ruby 3.4.1 (2024-12-25 revision 48d4efcb85) +YJIT +PRISM [arm64-darwin24] * Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- As reported in https://gitlab.com/gitlab-org/gitlab-development-kit/-/issues/2222 and https://trac.macports.org/ticket/70750, we've had numerous macOS users experience problems with compiling Ruby C++ extensions after upgrading to XCode 16. Users have had to fix their XCode setups and reinstall Ruby when this happens. It turns out that when Ruby can't build a CXX program, it essentially sets CXX to the `false` string. From https://github.com/ruby/ruby/blob/7317f96727725ca37ddb06011918deb841de371c/…: ``` AS_IF([test -n "${rb_there_is_in_fact_no_gplusplus_but_autoconf_is_cheating_us}"], [ AC_MSG_NOTICE([Test skipped due to lack of a C++ compiler.]) ], [test -n "${CXX}"], [ RUBY_WERROR_FLAG([ AC_MSG_CHECKING([whether CXXFLAGS is valid]) AC_LANG_PUSH(C++) AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[@%:@include <cstdio>]], [[]])], [AC_MSG_RESULT(yes)],[ AC_MSG_RESULT(no) # The message mentions CXXFLAGS, but CPPFLAGS might also affects. AC_MSG_WARN([something wrong with CXXFLAGS="$CXXFLAGS"]) CXX=false ``` This causes C++ extensions, such as `unf_ext`, to fail while attempting to compile native extensions. There are no error messages because `false` is executed, so users only see: ``` Installing unf_ext 0.0.8.2 with native extensions Gem::Ext::BuildError: ERROR: Failed to build gem native extension. current directory: /Users/myuser/.rvm/gems/ruby-3.3.7/gems/unf_ext-0.0.8.2/ext/unf_ext /Users/kerrizor/.rvm/rubies/ruby-3.3.7/bin/ruby extconf.rb checking for -lstdc++... yes creating Makefile current directory: /Users/myuser/.rvm/gems/ruby-3.3.7/gems/unf_ext-0.0.8.2/ext/unf_ext make DESTDIR\= sitearchdir\=./.gem.20250203-69237-u2oi17 sitelibdir\=./.gem.20250203-69237-u2oi17 clean current directory: /Users/myuser/.rvm/gems/ruby-3.3.7/gems/unf_ext-0.0.8.2/ext/unf_ext make DESTDIR\= sitearchdir\=./.gem.20250203-69237-u2oi17 sitelibdir\=./.gem.20250203-69237-u2oi17 compiling unf.cc make: *** [unf.o] Error 1 ``` `unf_ext` only checks whether `RbConfig::CONFIG['CXX']` is defined, not that it is `false`: https://github.com/knu/ruby-unf_ext/blob/c72a36d0a5ea9fe3950611b0f289fc68a2…. Questions: 1. Should CXX just be set to `nil`? Or should all C++ extensions be expected to check for `false`? The latter seems surprising to me. 2. Should there be a way to fail the Ruby build if a valid C++ compiler is not found? -- https://bugs.ruby-lang.org/

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[ruby-core:122892] [Ruby Bug#21525] Inconsistent execution order for methods with constant blocks
by joel＠drapper.me (Joel Drapper) 01 Aug '25

01 Aug '25

Issue #21525 has been reported by joel(a)drapper.me (Joel Drapper). ---------------------------------------- Bug #21525: Inconsistent execution order for methods with constant blocks https://bugs.ruby-lang.org/issues/21525 * Author: joel(a)drapper.me (Joel Drapper) * Status: Open * ruby -v: ruby 3.4.5 (2025-08-01 revision 07f7832cff) +PRISM [arm64-darwin24] * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- If you call a method and pass in a splat of an array with a block argument coerced from calling a method, Ruby maintains the expected execution order and the called method receives a copy of the array prior to modification. In this example, the output is `[1, 2, 3]` since the copy is made before the `bar` method can modify it. ```ruby ARRAY = [1, 2, 3] def bar ARRAY.pop -> {} end def example(*args, &) puts args end example(*ARRAY, &bar) ``` However, when passing a constant, the block coercion itself is able to modify the array. ```ruby ARRAY = [1, 2, 3] module Foo module Bar def self.to_proc ARRAY.pop -> {} end end end def example(*args, &) puts args end example(*ARRAY, &Foo::Bar) ``` Another way to trigger this is to define a `const_missing` method that modifies the array. ```ruby ARRAY = [1, 2, 3] module Foo def self.const_missing(name) ARRAY.pop -> {} end end def example(*args, &) puts args end example(*ARRAY, &Foo::Bar) ``` In both these cases, the output is `[1, 2]` instead of the expected `[1, 2, 3]`. -- https://bugs.ruby-lang.org/

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