Pure-Go Race Detector v0.8.4 (2025-12-19)

Production-ready race detection without CGO!

Works with CGO_ENABLED=0 - perfect for Docker, cloud functions, and embedded systems.

Bug Fixes

Issue #33: GetVersion() Missing 'v' Prefix

Release binaries returned version without 'v' prefix (0.8.3 instead of v0.8.3), causing racedetector test to fail on external projects:

go: errors parsing go.mod:
require github.com/kolkov/racedetector: version "0.8.3" invalid

Issue #34: Type Names in make/new Incorrectly Instrumented

Code like make([]*CustomType, 0) caused compilation errors because type names were incorrectly instrumented as variable reads:

SexpFunction (type) is not an expression

Changes

• GetVersion() now ensures 'v' prefix for non-dev versions
• extractReads() skips type expression AST nodes (ArrayType, MapType, ChanType, etc.)
• Special handling for make/new - skip first argument (always a type)

Found while testing on zygomys project.

Installation:

go install github.com/kolkov/racedetector/cmd/racedetector@v0.8.4

Quick Start:

racedetector build main.go
racedetector run main.go
racedetector test ./...

Documentation: https://github.com/kolkov/racedetector#readme

Pure-Go Race Detector v0.8.3 (2025-12-19T19:05:28Z)

Production-ready race detection without CGO!

Works with CGO_ENABLED=0 - perfect for Docker, cloud functions, and embedded systems.

Changelog

🐛 Bug Fixes

• 962743f: fix(instrument): SelectorExpr in IncDecStmt now instrumented (#30) (#31) (@kolkov)

Installation:

# Using go install (recommended):
go install github.com/kolkov/racedetector/cmd/racedetector@v0.8.3

# Or download binary for your platform above

Quick Start:

# Build with race detection:
racedetector build main.go

# Run with race detection:
racedetector run main.go

Documentation: https://github.com/kolkov/racedetector#readme

Report Issues: https://github.com/kolkov/racedetector/issues

Pure-Go Race Detector v0.8.2

Production-ready race detection without CGO!

Works with CGO_ENABLED=0 - perfect for Docker, cloud functions, and embedded systems.

🐛 Bug Fix: Issue #27 - Pointer Dereferences Not Instrumented

Critical bug found by @thepudds (Go Team member)

Pointer dereferences like *ptr++ were not being instrumented, causing false negatives:

func update(ptr *int) {  // ptr doesn't escape (correct)
    *ptr++               // BUT *ptr accesses potentially shared memory!
}

Root cause: Go parser uses *ast.StarExpr for pointer dereference in IncDecStmt, but our code only checked *ast.UnaryExpr.

Changes:

• Added *ast.StarExpr handling in visitor.go
• Added test cases for Issue #27 reproduction
• Race now correctly detected in @thepudds example

Before fix: 0 writes, 0 reads instrumented for *ptr++
After fix: Race correctly detected ✅

Acknowledgments

Thanks to @thepudds for finding this critical bug and providing the reproduction case!

Installation

# Using go install (recommended):
go install github.com/kolkov/racedetector/cmd/racedetector@v0.8.2

# Or download binary for your platform above

Quick Start

# Build with race detection:
racedetector build main.go

# Run with race detection:
racedetector run main.go

# Test with race detection:
racedetector test ./...

Documentation: https://github.com/kolkov/racedetector#readme
Report Issues: https://github.com/kolkov/racedetector/issues

Pure-Go Race Detector v0.8.1

Production-ready race detection without CGO!

What's New

Escape Analysis Integration

• Uses compiler go build -gcflags="-m" to detect stack-local variables
• 30-50% reduction in instrumentation on real codebases
• Named return value false positives eliminated

New toolexec Command

go build -toolexec="racedetector toolexec" ./...

Intercepts compile calls for complex build systems and IDE integration.

Tested On

• zygomys (Issue #17): lexer.go 14 writes/35 reads → 9 writes/18 reads

Installation

go install github.com/kolkov/racedetector/cmd/racedetector@v0.8.1

Fixes

• #17 - False positives on named return values

Full Changelog: v0.7.2...v0.8.1

Pure-Go Race Detector v0.7.2

Production-ready race detection without CGO!

Works with CGO_ENABLED=0 - perfect for Docker, cloud functions, and embedded systems.

What's Fixed

Stack Trace Display (Issue #17)

• Expanded isInternalStackFrame() filter to cover all racedetector packages
• Updated captureCallerPC() to skip 6 frames for accurate user code PC
• Test functions are now correctly shown in stack traces

False Positives on Stack-Local Variables (Issue #20)

• Skip instrumentation of named return values (stack-local)
• Skip instrumentation of function parameters (pass-by-value copies)
• Added isStackLocal() check in instrumentor

Phase 2 Roadmap

Detailed tasks created for further false positive reduction:

• #21: Loop variables (~30% reduction)
• #22: Short declarations (~40% reduction)
• #23: go/types integration (~20% reduction)

Installation:

# Using go install (recommended):
go install github.com/kolkov/racedetector/cmd/racedetector@v0.7.2

# Or download binary for your platform above

Quick Start:

# Build with race detection:
racedetector build main.go

# Run with race detection:
racedetector run main.go

Documentation: https://github.com/kolkov/racedetector#readme

Report Issues: https://github.com/kolkov/racedetector/issues

Pure-Go Race Detector v0.7.1 - Hotfix Release

Production-ready race detection without CGO!

Works with CGO_ENABLED=0 - perfect for Docker, cloud functions, and embedded systems.

Bug Fixes (Thanks @glycerine!)

Issue #15: Test command flags

• -c flag now works correctly (compile only, don't run)
• -o flag now works correctly (output file path)
• Version injection fixed (was hardcoded v0.4.10)

Issue #16: CGO file handling

• CGO files (import "C") are now detected and copied unchanged
• Skips instrumentation to avoid C symbol errors

Issue #17: Stack traces

• Stack traces now show user code location instead of internal frames
• Filters out OnWrite, OnRead, runtime.* frames

Performance Note

Stack trace capture adds ~145ns per memory access (runtime.Callers baseline).
Overall overhead remains within <20x target.
Further optimization tracked in Issue #18.

Installation

# Using go install (recommended):
go install github.com/kolkov/racedetector/cmd/racedetector@v0.7.1

# Or download binary for your platform above

Quick Start

# Build with race detection:
racedetector build ./...

# Run with race detection:
racedetector run main.go

# Test with race detection:
racedetector test -c -o mytest.exe ./...

Full Changelog: https://github.com/kolkov/racedetector/blob/main/CHANGELOG.md
Documentation: https://github.com/kolkov/racedetector#readme
Report Issues: https://github.com/kolkov/racedetector/issues

v0.7.0 - Major Performance Optimizations

Target: <20x overhead (down from ~100x)

This release delivers major performance optimizations through lazy evaluation, lock-free data structures, and memory pooling techniques.

Performance Improvements

Technical Details

Lazy Stack Capture

• Removed CaptureStack() from hot path
• Before: ~329ns per write (full stack capture)
• After: ~127ns per write (PC only, lazy full capture on race)

Lock-Free VarState

• Hot-path fields now use atomic.Uint64, atomic.Int64, atomic.Uintptr
• Mutex only for complex operations (VectorClock promotion)

Sharded Shadow Memory

• 256 shards instead of single sync.Map
• Cache-line padding prevents false sharing
• Reduces contention under concurrent load

VectorClock Pooling

• sync.Pool for VectorClock reuse
• Before: 1,009 allocations per benchmark
• After: 3 allocations per benchmark

Quality

• 359/359 race detection tests passing
• 0 linter issues
• 100% backward compatible

Installation

go install github.com/kolkov/racedetector/cmd/racedetector@v0.7.0

Acknowledgments

Research Papers:

• FastTrack: "Efficient and Precise Dynamic Race Detection" (PLDI 2009)
• SmartTrack: "Efficient Predictive Race Detection" (PLDI 2020)
• ThreadSanitizer design documents

v0.6.0 - Unsynchronized Access Detection

100% test reliability for race detection tests!

Fixed

Unsynchronized Access Detection

• GoStart/GoEnd instrumentation: VectorClock inheritance from parent to child goroutines
• SmartTrack TOCTOU race fix: CAS-based atomic ownership claim
• Spawn context FIFO ordering: Strict first-spawn-first-child matching
• sync.Map reassignment race: Safe map clearing via Range+Delete

CI Reliability

• Added GOMAXPROCS=1 to CI (same workaround as official Go race tests)
• Test reliability: 70% → 100%

Added

Go Race Test Suite

• 359/359 test scenarios from official Go race detector
• 21 test category files covering all race patterns
• 100% pass rate

Changed

• Professional README rewrite (662 → 189 lines)

Installation:

go install github.com/kolkov/racedetector/cmd/racedetector@v0.6.0

Usage:

racedetector build -o app main.go
racedetector run main.go
racedetector test ./...

Documentation: https://github.com/kolkov/racedetector#readme

Pure-Go Race Detector v0.5.2 (2025-12-10T11:15:55Z)

Production-ready race detection without CGO!

Works with CGO_ENABLED=0 - perfect for Docker, cloud functions, and embedded systems.

Changelog

🐛 Bug Fixes

• f8a01d2: fix(goid): Correct offsets for Go 1.23/1.24/1.25 (@kolkov)

Installation:

# Using go install (recommended):
go install github.com/kolkov/racedetector/cmd/racedetector@v0.5.2

# Or download binary for your platform above

Quick Start:

# Build with race detection:
racedetector build main.go

# Run with race detection:
racedetector run main.go

Documentation: https://github.com/kolkov/racedetector#readme

Report Issues: https://github.com/kolkov/racedetector/issues

Pure-Go Race Detector v0.4.10 (2025-12-10T01:32:34Z)

Production-ready race detection without CGO!

Works with CGO_ENABLED=0 - perfect for Docker, cloud functions, and embedded systems.

Changelog

🐛 Bug Fixes

• bb8950f: fix(test): Run go mod tidy in src directory to update go.sum (@kolkov)

Installation:

# Using go install (recommended):
go install github.com/kolkov/racedetector/cmd/racedetector@v0.4.10

# Or download binary for your platform above

Quick Start:

# Build with race detection:
racedetector build main.go

# Run with race detection:
racedetector run main.go

Documentation: https://github.com/kolkov/racedetector#readme

Report Issues: https://github.com/kolkov/racedetector/issues