feat: support non libc allocators

[not-matthias]

• feat(memtrack): accept IPC before creating tracker to avoid timeouts
• chore: print number of events written to disk
• feat(memtrack): track memalign calls
• feat(memtrack): support dynamically and statically linked allocators

[codspeed-hq]

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing cod-1715-support-non-libc-allocators (6545b69) with main (1ac1eae)}

Summary

✅ 4 untouched benchmarks

[Copilot]

Pull request overview

This pull request enhances the memtrack eBPF-based memory tracking system to support multiple memory allocators beyond the standard libc. The changes enable tracking of statically and dynamically linked allocators like jemalloc and mimalloc, which are commonly used in Rust and other performance-critical applications.

Changes:

• Refactored IPC connection initialization to happen before creating the Tracker instance to avoid timeouts
• Added comprehensive allocator discovery system supporting libc, jemalloc, and mimalloc (both static and dynamic linking)
• Extended eBPF probe attachment to support allocator-specific symbol names and added memalign tracking

Reviewed changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
crates/memtrack/src/main.rs	Reordered IPC connection to happen before tracker initialization; added event counter logging
crates/memtrack/src/libc.rs	Removed old libc-specific path discovery (replaced by new allocators module)
crates/memtrack/src/lib.rs	Updated exports to include new AllocatorKind and AllocatorLib types
crates/memtrack/src/ebpf/tracker.rs	Updated to use new allocator discovery system instead of libc-specific logic
crates/memtrack/src/ebpf/memtrack.rs	Refactored probe attachment macros; added allocator-specific probe attachment methods
crates/memtrack/src/ebpf/c/memtrack.bpf.c	Added memalign probe support
crates/memtrack/src/allocators/mod.rs	New allocator discovery framework defining AllocatorKind enum and AllocatorLib struct
crates/memtrack/src/allocators/dynamic.rs	Implements discovery of dynamically linked allocator libraries across various Linux distributions
crates/memtrack/src/allocators/static_linked.rs	Implements discovery of statically linked allocators in CodSpeed analysis binaries
crates/memtrack/Cargo.toml	Added object crate dependency for ELF symbol parsing
Cargo.lock	Updated with object crate dependency

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[Copilot]

The attach_standard_probes method is used differently for Libc vs. non-libc allocators. For Libc (line 298), the result is returned and can fail the operation. However, for Jemalloc and Mimalloc (lines 302, 307), the result is explicitly discarded with let _ = .... This inconsistency could be confusing. Consider documenting why the result is discarded for non-libc allocators, or refactoring to make the intent clearer (e.g., a separate method like try_attach_standard_probes that never fails).

[GuillaumeLagrange]

olgtm