Check Memory Leaks

This skill uses valgrind to detect memory leaks and memory errors in YARS.

Usage

Automatically invoked when:

• User asks to check for memory leaks
• After refactoring memory management
• During observer pattern removal work
• Before major releases or commits

Steps

# Navigate to build directory
cd build

# Ensure debug build for better stack traces
cmake -DCMAKE_BUILD_TYPE=Debug .. && make -j4

# Run valgrind with leak check
valgrind --leak-check=full \
         --show-leak-kinds=all \
         --track-origins=yes \
         --verbose \
         --log-file=valgrind-output.txt \
         ./bin/yars --iterations 100 --xml ../xml/braitenberg.xml

# Display results
cat valgrind-output.txt

Success Criteria

• ✅ No definite memory leaks detected
• ✅ No invalid memory accesses
• ✅ All heap blocks properly freed
• ✅ Clean valgrind summary

Analysis

Valgrind reports to watch for:

• Definitely lost: Critical leaks that must be fixed
• Indirectly lost: Memory leaked due to parent structure
• Possibly lost: May indicate real leaks
• Still reachable: Memory not freed at exit (less critical)
• Invalid reads/writes: Memory access errors

Notes

• Valgrind significantly slows execution (10-30x slower)
• Use fewer iterations (100-500) to keep runtime reasonable
• Debug build provides better stack traces
• Some false positives possible from external libraries
• Focus on "definitely lost" and "invalid" errors first