Conceptual-Machines Crash Analysis
Parsing Crash Logs
Never read crash log files directly — they are huge and waste context. Use the parser script:
# Extract crashed thread only (default)
.claude/skills/crash-analysis/parse-crash.sh <crash-file>
# Extract all threads (when you need more context)
.claude/skills/crash-analysis/parse-crash.sh <crash-file> --all-threads
Supports both .ips (JSON, modern macOS) and .crash (text, older) formats.
Finding Crash Logs
macOS crash logs are stored at:
~/Library/Logs/DiagnosticReports/MAGDA-*.ips
To find the most recent crash:
ls -t ~/Library/Logs/DiagnosticReports/MAGDA-*.ips | head -1
Analysis Workflow
- Parse the crash log with the script
- Identify the crash type (SIGSEGV, SIGABRT, EXC_BAD_ACCESS, etc.)
- Look at the top frames for MAGDA code (source file + line number are included)
- If the crash is in a third-party plugin (e.g. "Kick 3", "Serum"), note it — host can't fix plugin bugs
- If the crash is in JUCE internals, check what MAGDA code triggered it (look further down the stack)
- Search the codebase for the relevant source file and line to understand the bug
Common Crash Patterns
| Signal | Meaning | Typical Cause |
|---|---|---|
| SIGSEGV (EXC_BAD_ACCESS) | Null/dangling pointer | Use-after-free, null deref |
| SIGABRT | Assertion/abort | JUCE assertion, malloc corruption, std::abort |
| EXC_BAD_INSTRUCTION | Illegal instruction | Undefined behavior, bad vtable |
| EXC_BREAKPOINT | Debugger trap | __builtin_trap, Swift precondition |
Plugin crashes during shutdown
If the crash is in a plugin dylib during exit() / __cxa_finalize_ranges, it's a buggy plugin static destructor. The _exit(0) workaround in magda_daw_main.cpp should prevent these.
Timer callback crashes
Crashes in juce::Timer::TimerThread::callTimers() often mean a component was deleted while its timer was still running. Check that stopTimer() is called in destructors.
Audio thread crashes
Crashes in threads named "JUCE Audio" or "Tracktion" are audio-thread issues. Common causes: allocating memory, locking mutexes, or accessing deleted objects from the audio callback.
Windows Crash Analysis (.dmp files)
Windows users send .dmp minidump files. Use the scripts below — never read .dmp files directly.
Quick parse (no symbols)
python3 .claude/skills/crash-analysis/parse-minidump.py /path/to/file.dmp
With PDB symbolization (function names + offsets)
From v0.4.6 onwards, each release includes MAGDA-X.Y.Z-Windows-x86_64.pdb.
Download it from the GitHub release assets, then:
python3 .claude/skills/crash-analysis/parse-minidump.py file.dmp --pdb MAGDA-X.Y.Z-Windows-x86_64.pdb
Semi-automated analysis (parse + Claude + optional Linear issue)
Requires: pip install anthropic
# Parse + Claude analysis (downloads PDB automatically for known versions)
ANTHROPIC_API_KEY=... GITHUB_TOKEN=... \
python3 .claude/skills/crash-analysis/analyze-crash.py \
--dump file.dmp --version 0.4.6
# Also create a Linear issue
ANTHROPIC_API_KEY=... GITHUB_TOKEN=... LINEAR_API_KEY=... LINEAR_TEAM_ID=... \
python3 .claude/skills/crash-analysis/analyze-crash.py \
--dump file.dmp --version 0.4.6 --create-issue
# With a local PDB (skips download)
ANTHROPIC_API_KEY=... \
python3 .claude/skills/crash-analysis/analyze-crash.py \
--dump file.dmp --pdb MAGDA.pdb
Reading the output
| Field | What to look for |
|---|---|
| Exception code | 0xC0000005 = access violation (most common) |
| AV address | 0x0 = null deref; 0xFFFFFFFFFFFFFFFF = sentinel/corruption |
| Rcx register | In x64, this is this — garbage here means the object is corrupt/freed |
| Stack scan | MAGDA.exe offsets narrow the subsystem; with PDB they resolve to function names |
Common Windows crash patterns
| Pattern | Likely cause |
|---|---|
| AV read at 0x0 | Null pointer dereference |
| AV read at 0xFFFFFFFFFFFFFFFF | Dangling std::list iterator or sentinel value used as pointer |
| Rcx = ASCII/UTF bytes | String buffer being used as this pointer — memory corruption or bad cast |
| Rbp = small integer (0, 1, 2) | Stack frame pointer corrupted — look for buffer overflows |
| Crash on project reopen | Serialization/deserialization bug, often with non-ASCII paths on Windows |