Crash reporter

The Firefox crash reporter is a separate binary that runs out-of-process whenever Firefox crashes. It captures a minidump, lets the user submit it, and uploads to Mozilla's crash backend (Socorro / crash-stats). Source: toolkit/crashreporter/.

Components

Path	Role
toolkit/crashreporter/breakpad-client/	Vendored Google Breakpad client used at crash time
toolkit/crashreporter/google-breakpad/	Vendored Breakpad symbol/minidump library
toolkit/crashreporter/client/app/	Modern Rust crash-reporter UI app
toolkit/crashreporter/crash_helper_server/	Rust helper process for crash collection
toolkit/crashreporter/crash_helper_client/	Rust client library used by Firefox
toolkit/crashreporter/minidump-analyzer/	Local symbolication and analysis
toolkit/crashreporter/mozwer-rust/	Windows Error Reporting integration
toolkit/crashreporter/nsExceptionHandler.{h,cpp}	The C++ glue that integrates Breakpad with Gecko

How it works

1. At startup, nsExceptionHandler installs a Breakpad signal handler.
2. On crash, Breakpad writes a minidump to disk.
3. The crash helper (out of process) coordinates collection and is spawned for each child-process crash to avoid re-crashing in the dying process.
4. On next launch, Firefox shows the crash reporter UI (the Rust app under client/app/), letting the user review and submit.
5. Submitted reports go to Mozilla's Socorro pipeline at crash-stats.mozilla.com.

Why Rust

The newer reporter components (client/app, crash_helper_server, crash_helper_client, mozwer-rust, minidump-analyzer/android/) are written in Rust because crash handling is one of the highest-stakes places in the codebase: a bug in crash code can prevent reports from arriving and hide regressions. Rust's safety properties reduce that risk.

Related

• Build system — these are workspace crates listed in Cargo.toml.
• Telemetry / Glean — crash counts and crash-related metrics flow through Glean too.