Skip to content

CS 631-01 Systems Foundations — Meeting Summary

  • Date: Feb 03, 2026
  • Time: 08:12 AM Pacific Time (US and Canada)
  • Meeting ID: 870 0988 0761

Quick Recap

The session focused on memory management in C and Rust, comparing stack and heap allocation, Rust’s ownership model, and its safety guarantees. Greg explained how Rust addresses common C pitfalls—such as memory leaks, dangling pointers, and buffer overflows—through strict compile-time memory safety rules (ownership, borrowing, lifetimes) and deterministic resource management (RAII), not through garbage collection. The class reviewed Rust features including vectors, enums, and traits, using side-by-side C and Rust examples to illustrate safer alternatives to manual memory management in C. Greg emphasized that while Rust’s model introduces initial complexity, it prevents common errors and leads to more reliable code.

Next Steps

  • Greg:
  • Post the next lab, new lecture notes, and a new GitHub repository for the class.

  • (Optional) Investigate and clarify the use of anonymous lifetime placeholders in Rust (possibly with input from Mehmed) for a future explanation.

  • Students:

  • Continue implementing the decode logic and Rust code for Lab 1, following the provided patterns.
  • After pushing Lab 1 work, clone the repository and run grade RS test on the Beagle machine to verify submission completeness and correctness before the due date.
  • Review the side-by-side C and Rust memory usage examples in the in-class repository to deepen understanding of memory management concepts.

Summary

Rust Memory and Lab Submission

  • Greg outlined the plan to deepen understanding of Rust’s memory model and its syntax/semantics.
  • He emphasized active engagement and feedback.
  • He reviewed the Lab 1 submission process, including Git workflows and use of the autograder.
  • Recommendation: verify submissions across environments before the deadline.

Code, Data, and Memory Concepts

  • Distinction clarified:
  • Program: the static artifact on disk.
  • Process: the executing instance in memory.
  • Operating system behavior:
  • Loads a program into memory with segments for code, stack, heap, and globals/statics.
  • Provides each process with an isolated virtual address space managed by the OS and processor (MMU).

C vs. Rust Memory Management

  • Both languages use stack and heap allocation; however, Rust adds safety through:
  • Ownership and borrowing rules.
  • Lifetimes ensuring references remain valid.
  • Deterministic destruction (RAII via Drop) for automatic deallocation—no garbage collector.
  • Examples demonstrated:
  • Allocation and deallocation in C versus Rust’s safe patterns.
  • How Rust prevents dangling pointers, memory leaks, and buffer overflows at compile time.
  • Additional Rust topics:
  • Functional features and type inference.
  • Vectors for dynamic data structures.
  • Use of tools like Clippy to detect non-idiomatic Rust code.
  • Students were encouraged to study the provided examples and apply best practices in their lab work.