[BUG] Bundled ripgrep fails on Raspberry Pi 5 due to jemalloc page size mismatch

Bug Report: Bundled ripgrep fails on Raspberry Pi 5 due to jemalloc page size mismatch

Summary

Custom slash commands in Claude Code fail to load on Raspberry Pi 5 (and potentially other 16KB page size ARM systems) because the bundled ripgrep binary was compiled with jemalloc configured for 4KB pages.

Environment

• Device: Raspberry Pi 5 Model B Rev 1.1
• OS: Debian GNU/Linux 12 (bookworm)
• Kernel: 6.12.47+rpt-rpi-2712
• Architecture: aarch64
• Page Size: 16384 bytes (16KB)
• Claude Code Version: 2.0.14

Steps to Reproduce

1. Install Claude Code on Raspberry Pi 5
2. Create custom slash commands in .claude/commands/ with proper frontmatter
3. Start Claude Code session
4. Try to use custom slash commands (e.g., /my-command)
5. Commands are not recognized

Root Cause

The bundled ripgrep binary at ~/.claude/local/node_modules/@anthropic-ai/claude-code/vendor/ripgrep/arm64-linux/rg fails with jemalloc error:

<jemalloc>: Unsupported system page size
memory allocation of 160 bytes failed

This occurs because:

1. The binary was compiled with jemalloc configured for 4KB pages (common in cloud/server ARM systems)
2. Raspberry Pi 5 uses 16KB pages (via getconf PAGESIZE = 16384)
3. jemalloc's internal structures are sized at compile-time based on page size
4. When there's a mismatch, memory allocation fails immediately

Impact

• Custom slash commands don't load - The command scanning process silently fails
• No error shown to user - The failure happens during startup and is only visible in debug logs
• Affects all 16KB page ARM systems - Not just Raspberry Pi 5

Debug Log Evidence

From ~/.claude/debug/*.txt:

[ERROR] Error: Command failed: /home/pi/.claude/local/.../rg --files --hidden --follow --glob *.md /path/.claude/commands
[DEBUG] Total plugin commands loaded: 0
[DEBUG] Slash commands included in SlashCommand tool:

Workaround

Replace the bundled ripgrep with a symlink to system ripgrep (compiled for correct page size):

# Backup broken binary
mv ~/.claude/local/node_modules/@anthropic-ai/claude-code/vendor/ripgrep/arm64-linux/rg \
   ~/.claude/local/node_modules/@anthropic-ai/claude-code/vendor/ripgrep/arm64-linux/rg.broken

# Link to system ripgrep
ln -s /usr/bin/rg \
   ~/.claude/local/node_modules/@anthropic-ai/claude-code/vendor/ripgrep/arm64-linux/rg

Or use the automated fix script:

#!/bin/bash
# fix_claude_ripgrep.sh
set -e

RIPGREP_PATH="$HOME/.claude/local/node_modules/@anthropic-ai/claude-code/vendor/ripgrep/arm64-linux"
RIPGREP_BINARY="$RIPGREP_PATH/rg"
SYSTEM_RIPGREP="/usr/bin/rg"

# Check page size
PAGE_SIZE=$(getconf PAGESIZE)
if [ "$PAGE_SIZE" != "16384" ]; then
    echo "Page size is ${PAGE_SIZE} bytes, not 16KB. No fix needed."
    exit 0
fi

# Check if already fixed
if [ -L "$RIPGREP_BINARY" ]; then
    echo "Already fixed: $(readlink -f "$RIPGREP_BINARY")"
    exit 0
fi

# Apply fix
[ -f "$RIPGREP_BINARY" ] && mv "$RIPGREP_BINARY" "$RIPGREP_BINARY.broken"
ln -s "$SYSTEM_RIPGREP" "$RIPGREP_BINARY"
echo "Fix applied! Restart Claude Code for custom slash commands to load."

Suggested Solutions

Option 1: Compile for 16KB pages (Quick Fix)
Compile the arm64-linux ripgrep binary with jemalloc configured for 16KB pages, or use the system allocator instead of jemalloc.

Option 2: Bundle both versions (Better)

• Bundle both arm64-linux-4k/rg and arm64-linux-16k/rg
• Detect page size at runtime and use appropriate binary

Option 3: Fallback to system ripgrep (Best)

• Detect if bundled ripgrep fails
• Automatically fallback to system ripgrep if available
• Show warning if neither works

Option 4: Drop bundled ripgrep for ARM (Pragmatic)

• Check for system ripgrep on ARM systems during installation
• Only bundle ripgrep for platforms where it's commonly missing (Windows, older systems)

Why This Matters

• Apple Silicon Macs work fine - The arm64-darwin binary is properly compiled for 16KB pages
• Growing ARM adoption - More developers using Raspberry Pi, ARM servers, Apple Silicon
• Silent failure - Users don't know why their custom commands don't work

Related Issues

This is distinct from:

• #3569 (aarch64 architecture detection) - That's about installation
• #2151 (MCP servers on Pi) - That's about MCP, not core ripgrep functionality
• Other ripgrep issues - Those are about usage, not compilation incompatibility

Additional Context

• System ripgrep (/usr/bin/rg version 13.0.0) works perfectly on the same system
• The issue persists across Claude Code updates (binary is re-bundled each time)
• This affects any functionality that relies on ripgrep for file scanning