Valgrind User Manual

Table of Contents

1. Introduction

1.1. An Overview of Valgrind

1.2. How to navigate this manual

2. Using and understanding the Valgrind core

2.1. What Valgrind does with your program

2.2. Getting started

2.3. The Commentary

2.4. Reporting of errors

2.5. Suppressing errors

2.6. Command-line flags for the Valgrind core

2.6.1. Tool-selection option

2.6.2. Basic Options

2.6.3. Error-related options

2.6.4. malloc()-related Options

2.6.5. Uncommon Options

2.6.6. Debugging Valgrind Options

2.6.7. Setting default Options

2.7. Support for Threads

2.8. Handling of Signals

2.9. Building and Installing Valgrind

2.10. If You Have Problems

2.11. Limitations

2.12. An Example Run

2.13. Warning Messages You Might See

3. Using and understanding the Valgrind core: Advanced Topics

3.1. The Client Request mechanism

3.2. Function wrapping

3.2.1. A Simple Example

3.2.2. Wrapping Specifications

3.2.3. Wrapping Semantics

3.2.4. Debugging

3.2.5. Limitations - control flow

3.2.6. Limitations - original function signatures

3.2.7. Examples

4. Memcheck: a heavyweight memory checker

4.1. Kinds of bugs that Memcheck can find

4.2. Command-line flags specific to Memcheck

4.3. Explanation of error messages from Memcheck

4.3.1. Illegal read / Illegal write errors

4.3.2. Use of uninitialised values

4.3.3. Illegal frees

4.3.4. When a block is freed with an inappropriate deallocation function

4.3.5. Passing system call parameters with inadequate read/write permissions

4.3.6. Overlapping source and destination blocks

4.3.7. Memory leak detection

4.4. Writing suppression files

4.5. Details of Memcheck's checking machinery

4.5.1. Valid-value (V) bits

4.5.2. Valid-address (A) bits

4.5.3. Putting it all together

4.6. Client Requests

4.7. Memory Pools: describing and working with custom allocators

4.8. Debugging MPI Parallel Programs with Valgrind

4.8.1. Building and installing the wrappers

4.8.2. Getting started

4.8.3. Controlling the wrapper library

4.8.4. Abilities and limitations

4.8.5. Writing new wrappers

4.8.6. What to expect when using the wrappers

5. Cachegrind: a cache and branch profiler

5.1. Cache and branch profiling

5.1.1. Overview

5.1.2. Cache simulation specifics

5.1.3. Branch simulation specifics

5.2. Profiling programs

5.2.1. Output file

5.2.2. Cachegrind options

5.2.3. Annotating C/C++ programs

5.2.4. Annotating assembly code programs

5.2.5. Forking Programs

5.3. cg_annotate options

5.3.1. Warnings

5.3.2. Things to watch out for

5.3.3. Accuracy

5.4. Merging profiles with cg_merge

5.5. Acting on Cachegrind's information

5.6. Implementation details

5.6.1. How Cachegrind works

5.6.2. Cachegrind output file format

6. Callgrind: a call graph profiler

6.1. Overview

6.1.1. Functionality

6.1.2. Basic Usage

6.2. Advanced Usage

6.2.1. Multiple profiling dumps from one program run

6.2.2. Limiting the range of collected events

6.2.3. Avoiding cycles

6.3. Command line option reference

6.3.1. Miscellaneous options

6.3.2. Dump creation options

6.3.3. Activity options

6.3.4. Data collection options

6.3.5. Cost entity separation options

6.3.6. Cache simulation options

7. Helgrind: a thread error detector

7.1. Overview

7.2. Detected errors: Misuses of the POSIX pthreads API

7.3. Detected errors: Inconsistent Lock Orderings

7.4. Detected errors: Data Races

7.4.1. A Simple Data Race

7.4.2. Helgrind's Memory State Machine

7.4.3. Transfers of Exclusive Ownership Between Threads

7.4.4. Restoration of Exclusive Ownership

7.4.5. A Summary of the Race Detection Algorithm

7.4.6. Interpreting Race Error Messages

7.5. Hints and Tips for Effective Use of Helgrind

7.6. Helgrind Options

7.7. A To-Do List for Helgrind

8. Massif: a heap profiler

8.1. Heap profiling

8.2. Using Massif

8.2.1. An Example Program

8.2.2. The Output Preamble

8.2.3. The Output Graph

8.2.4. The Snapshot Details

8.2.5. Forking Programs

8.3. Massif Options

8.4. ms_print Options

8.5. Massif's output file format

9. Nulgrind: the "null" tool

10. Lackey: a simple profiler and memory tracer

10.1. Overview

10.2. Lackey Options

11. Writing a New Valgrind Tool

11.1. Introduction

11.1.1. Tools

11.2. Writing a Tool

11.2.1. How tools work

11.2.2. Getting the code

11.2.3. Getting started

11.2.4. Writing the code

11.2.5. Initialisation

11.2.6. Instrumentation

11.2.7. Finalisation

11.2.8. Other Important Information

11.2.9. Words of Advice

11.3. Advanced Topics

11.3.1. Suppressions

11.3.2. Documentation

11.3.3. Regression Tests

11.3.4. Profiling

11.3.5. Other Makefile Hackery

11.3.6. Core/tool Interface Versions

11.4. Final Words