CCC (Claude's C Compiler), built entirely by Claude AI, successfully compiles C code including all 2,844 files from Linux kernel 6.9 without errors, but fails at the linking stage. While functionally correct on SQLite benchmarks, CCC-compiled binaries run 737-158,000x slower than GCC due to excessive register spilling, lack of optimization tiers (all -O flags produce identical output), and 2.7-3x code bloat. CCC uses 5.9x more memory during compilation and produces binaries without proper debug symbols. The compiler demonstrates AI's capability to build complex software but remains impractical for production use compared to mature compilers like GCC.
Table of contents
IntroductionWhat is a Compiler, Assembler and Linker?Why Compilers Are BeastsWhy the Compiler Is the “Easy” PartWhy SQLite and Not the Linux Kernel?Test SetupMethodologyResults SummaryLinux Kernel 6.9 CompilationSQLite 3.46 BenchmarkPer-Query AnalysisRoot Cause Analysis – Why CCC Code is SlowKey FindingsThe Hello World That Could NotConclusionsReproducingDisclaimerSort: