From: "yahonda (Yasuo Honda) via ruby-core" <ruby-core@...>
Date: 2026-04-21T07:02:13+00:00
Subject: [ruby-core:125329] [Ruby Bug#22009] ERROR: AddressSanitizer: attempting to call malloc_usable_size() for pointer which is not owned: with ASAN and DEBUG enabled build

Issue #22009 has been updated by yahonda (Yasuo Honda).


With Claude Code help,  It only reproduces with both ASAN and DEBUG options enabled. But not sure if this is the right fix though.

https://github.com/ruby/ruby/commit/e47063e5bc52929924b633cffed33fc9132030c4

----------------------------------------
Bug #22009: ERROR: AddressSanitizer: attempting to call malloc_usable_size() for pointer which is not owned: with ASAN and DEBUG enabled build
https://bugs.ruby-lang.org/issues/22009#change-117080

* Author: yahonda (Yasuo Honda)
* Status: Open
* Backport: 3.3: UNKNOWN, 3.4: UNKNOWN, 4.0: UNKNOWN
----------------------------------------
### Background

I am using ruby-head built and deployed by https://github.com/ruby/ruby-dev-builder for my repository.
https://github.com/rsim/oracle-enhanced/blob/master/.github/workflows/ruby_head.yml

Recently, the `ruby-head` version has not been updated since `ruby 4.1.0dev (2026-03-29T05:57:51Z :detached: f9175a9e5f) +PRISM [aarch64-linux]`.

According to the ruby-dev-builder log file:

- The last successful build : https://github.com/ruby/ruby-dev-builder/actions/runs/23716940676
- The first failing build :https://github.com/ruby/ruby-dev-builder/actions/runs/23763490942
- The latest failing build : https://github.com/ruby/ruby-dev-builder/actions/runs/24686105004

### Steps to reproduce

```
mkdir work
cd work
git clone https://github.com/ruby/ruby.git
git clone https://github.com/ruby/ruby-dev-builder.git

cd ruby

../ruby-dev-builder/asan_libs.rb \
  --prefix=$HOME/.rubies/ruby-asan \
  --cc=clang \
  --cflags='-fsanitize=address -fno-omit-frame-pointer -ggdb3 -O3' \
  --ldflags="-Wl,-rpath=$HOME/.rubies/ruby-asan/lib" \
  --makeopts=-j4

export cppflags="-DENABLE_PATH_CHECK=0 -DRUBY_DEBUG=1 -DVM_CHECK_MODE=1 -DUSE_MN_THREADS=0"
export optflags="-O3 -fno-omit-frame-pointer"
export debugflags="-fsanitize=address -ggdb3"
export CC=clang
export cflags="-I$HOME/.rubies/ruby-asan/include"
export LDFLAGS="-L$HOME/.rubies/ruby-asan/lib -Wl,-rpath=$HOME/.rubies/ruby-asan/lib"
export RUBY_TEST_TIMEOUT_SCALE=5

./autogen.sh
./configure --prefix=$HOME/.rubies/ruby-asan --enable-shared --disable-install-doc --enable-yjit
make -j4 && make install
make test-spec MSPECOPT="spec/ruby/library/objectspace/dump_all_spec.rb" 2>&1 | tee error.log
```

### Expected behavior
This spec should pass.

### Actual behavior
It raises `ERROR: AddressSanitizer: attempting to call malloc_usable_size() for pointer which is not owned:`


---Files--------------------------------
error.log (1.69 MB)


-- 
https://bugs.ruby-lang.org/
______________________________________________
 ruby-core mailing list -- ruby-core@ml.ruby-lang.org
 To unsubscribe send an email to ruby-core-leave@ml.ruby-lang.org
 ruby-core info -- https://ml.ruby-lang.org/mailman3/lists/ruby-core.ml.ruby-lang.org/