Welcome to Fil-C, an actively supported memory safe implementation of the C and C++ programming languages you already know and love.
Visit fil-c.org → On Hacker News Sep 2025 – Jun 2026
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Fil-C uses a parallel concurrent on-the-fly grey-stack Dijkstra accurate non-moving garbage collector called FUGC (Fil's Unbelievable Garbage Collector). You can find the source code for the collector itself in fugc.c , though be warned, that code cannot possibly work without lots of support logic in the rest of the…
Memory safety and sandboxing are two different things. It's reasonable to think of them as orthogonal: you could have memory safety but not be sandboxed, or you could be sandboxed but not memory safe.
This document describes how Fil-C supports longjmp , setjmp , setcontext , getcontext , makecontext , and swapcontext in a totally memory-safe way. In particular, no misuse of those APIs in Fil-C can lead to stack corruption or any other violation of Fil-C's capability model.
Since Fil-C 0.685, memory-safe inline assembly is supported on both X86_64 and ARM64.
Fil-C achieves memory safety even for programs that behave adversarially. That includes casting function pointers to the wrong signature and then calling them, exporting a function with one signature in one module and then importing it with a different signature in another, or even exporting a symbol as a function in…
Pizlix is LFS (Linux From Scratch) 12.2 with some added components, where userland is compiled with Fil-C. This means you get the most memory safe Linux-like OS currently available.