[BUG] claude segfaults, so does install.sh

[michkrom]

Preflight Checklist

• I have searched existing issues and this hasn't been reported yet
• This is a single bug report (please file separate reports for different bugs)
• I am using the latest version of Claude Code

What's Wrong?

Arch Endevour latest as of 8/24/26.
Running install script via bash -> seg fault
Installing via npm, ok, but then claude -> seg fault

What Should Happen?

Duh!

Error Messages/Logs

$ claude
Segmentation fault         (core dumped) claude
$ curl -fsSL https://claude.ai/install.sh | bash
Setting up Claude Code...
bash: line 226:  8777 Segmentation fault         (core dumped) "$binary_path" install ${TARGET:+"$TARGET"}
Installation was killed before it could finish (exit code 139).

Steps to Reproduce

curl -fsSL https://claude.ai/install.sh | bash

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

No response

Claude Code Version

latest

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

No response

[michkrom]

(No debugging symbols found in /home/m/.nvm/versions/node/v26.7.0/lib/node_modules/@anthropic-ai/claude-code/bin/claude.exe)
(gdb) r
Starting program: /home/m/.nvm/versions/node/v26.7.0/lib/node_modules/@anthropic-ai/claude-code/bin/claude.exe
Downloading 1.34 M separate debug info for /lib64/ld-linux-x86-64.so.2
Downloading 20.27 K separate debug info for /usr/lib/libpthread.so.0
Downloading 26.15 K separate debug info for /usr/lib/librt.so.1
Downloading 10.81 M separate debug info for /usr/lib/libc.so.6
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
Downloading 19.52 K separate debug info for /usr/lib/libdl.so.2
Downloading 4.02 M separate debug info for /usr/lib/libm.so.6

Program received signal SIGSEGV, Segmentation fault.
0x0000000001d10458 in free ()
(gdb) bt
#0 0x0000000001d10458 in free ()
#1 0x00007ffff7c3530a in __newlocale (category_mask=, locale=, base=) at newlocale.c:291
#2 0x0000000001abd282 in ?? ()
#3 0x00007ffff7c9d7fc in __pthread_once_slow (once_control=0x54deb1c, init_routine=0x1abc1d0) at pthread_once.c:116
#4 0x00007ffff7c9d879 in ___pthread_once (once_control=, init_routine=) at pthread_once.c:143
#5 0x0000000001abc2d2 in ?? ()
#6 0x0000000001ace6cf in ?? ()
#7 0x0000000001abdc0a in ?? ()
#8 0x0000000001abe9c4 in ?? ()
#9 0x00007ffff7c9d7fc in __pthread_once_slow (once_control=0x54deb28, init_routine=0x1abe990) at pthread_once.c:116
#10 0x00007ffff7c9d879 in ___pthread_once (once_control=, init_routine=) at pthread_once.c:143
#11 0x0000000001abea15 in ?? ()
#12 0x0000000001abead7 in ?? ()
#13 0x0000000001abb922 in ?? ()
#14 0x0000000001abb724 in ?? ()
#15 0x0000000001aadadd in ?? ()
#16 0x00007ffff7c27892 in __libc_start_main_impl (main=0x1b1b550, argc=1, argv=0x7fffffffe158, init=0x1aada90, fini=, rtld_fini=, stack_end=0x7fffffffe148) at ../csu/libc-start.c:355
#17 0x0000000001953a2e in ?? ()
(gdb)

[mrwiora]

Running on archlinux - latest updates, kernel 7.1.9, glibc 2.44+r24 - same issue
temporary returning to old version works

~/.local/share/claude/versions/2.1.241 was the latest I used.

[donperi]

Same issue, CachyOS

[michkrom]

This version works:
npm install -g @anthropic-ai/claude-code@2.1.205

[sy-kr]

Same issue - Arch kernel 7.1.5, glibc 2.44. latest Claude code update. Native install script also segfaults.

[LucFauvel]

Same issue here with kernel 7.1.9-arch1-2, glibc 2.44. Update bricked it.

#0  0x0000000001d10458 in free ()
#1  0x00007ffff7c3530a in __newlocale (category_mask=<optimized out>, locale=<optimized out>, base=<optimized out>) at newlocale.c:291
#2  0x0000000001abd282 in ?? ()
#3  0x00007ffff7c9d7fc in __pthread_once_slow (once_control=0x54deb1c, init_routine=0x1abc1d0) at pthread_once.c:116
#4  0x00007ffff7c9d879 in ___pthread_once (once_control=<optimized out>, init_routine=<optimized out>) at pthread_once.c:143
#5  0x0000000001abc2d2 in ?? ()
#6  0x0000000001ace6cf in ?? ()
#7  0x0000000001abdc0a in ?? ()
#8  0x0000000001abe9c4 in ?? ()
#9  0x00007ffff7c9d7fc in __pthread_once_slow (once_control=0x54deb28, init_routine=0x1abe990) at pthread_once.c:116
#10 0x00007ffff7c9d879 in ___pthread_once (once_control=<optimized out>, init_routine=<optimized out>) at pthread_once.c:143
#11 0x0000000001abea15 in ?? ()
#12 0x0000000001abead7 in ?? ()
#13 0x0000000001abb922 in ?? ()
#14 0x0000000001abb724 in ?? ()
#15 0x0000000001aadadd in ?? ()
#16 0x00007ffff7c27892 in __libc_start_main_impl (main=0x1b1b550, argc=1, argv=0x7fffffffdce8, init=0x1aada90, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffdcd8)
    at ../csu/libc-start.c:355
#17 0x0000000001953a2e in ?? ()

Crash doesn't happen on glibc 2.43

Seems to be a bun issue. mimalloc's free is declared and overwriting glibc's free and in glibc 2.44, that free is used earlier in __newlocale exposing the issue.

Issue seems present even in Microsoft's base mimalloc repo.

Turns out issue is unreachable on upstream Microsoft mimalloc, but it is reachable in Bun's fork. Opened a PR. oven-sh/mimalloc#29

[bovinemagnet]

same issue on arch linux (Garuda Linux)

[davgar99]

Environment

• Arch Linux, kernel 7.1.9-arch1-2
• glibc 2.44+r24+g16be1518495f-1
• x86-64
• Node.js v26.7.0
• npm 12.0.2

Version testing

Claude Code	Installation method	Result
2.1.243	Native installer/bootstrap	Segfault, exit 139
2.1.243	Direct checksum-verified native binary	Segfault
2.1.243	npm package	Same native binary and segfault
2.1.242	npm package	Segfault
2.1.241	npm package	Works normally

Both claude --version and claude --help fail on versions 2.1.242 and 2.1.243. Both commands work on 2.1.241 without an LD_PRELOAD compatibility wrapper.

The stack trace matches the one already reported:

free()
__newlocale() at newlocale.c:291

Additional checks

• The installed glibc package passes Arch package-integrity checks.
• Installing glibc-locales did not help.
• Version 2.1.243 still crashes under both C.UTF-8 and en_US.UTF-8.
• Other applications using the same glibc installation work normally.
• This appears consistent with an early allocator/mimalloc initialization or symbol-interposition regression, rather than missing locale data or a corrupted glibc installation.

Installer problem

The native install.sh script always downloads and executes the latest Claude binary as its bootstrap, even when the user requests stable or a specific older version.

Because the 2.1.243 bootstrap itself segfaults, affected users cannot use the official script to install an older version or the stable channel.

Current workaround

Install the last working npm release:

npm install -g @anthropic-ai/claude-code@2.1.241

Temporarily disable automatic updates:

{
  "env": {
    "DISABLE_AUTOUPDATER": "1"
  }
}

It would be helpful to fix both:

1. The native binary’s compatibility with glibc 2.44.
2. The installer’s reliance on the latest binary when an older target was explicitly requested.

[LucFauvel]

Fixed in 2.1.246