LC

Debug a Multithreaded Race Condition

hard3/8

Write a GDB Python Pretty-Printer Use rr Record-and-Replay for Time-Travel Debugging

Language

Compiler

2.0s Limit 256MB

Implementation

Write a C program using pthreads that demonstrates an intentional race condition on a shared counter, and prints explanations of how to detect it with GDB.

Requirements:

Create multiple pthreads that increment a shared counter
Do NOT use mutexes to show the race condition
Print the expected GDB commands to analyze the race
Output must mention threads, race conditions, and the counter
Explain info threads, thread apply all bt, and watchpoints

Why This Matters

`thread apply all bt` and `set scheduler-locking on` are the exact GDB commands engineers reach for when triaging production deadlocks and data races in multithreaded servers, since tools like ThreadSanitizer flag the race but GDB is what confirms the interleaving that caused it. This unprotected shared_counter++ pattern is the textbook race condition every concurrency bug report eventually traces back to.

Hints

0 / 3 revealed

Validation Suite

main.c

Workspace 1.0