Ccache vs clcache

Ccache is a build tool that can reduce repeated compilation work by storing prior results and recognizing when a single-file compilation recurs. It supports compilers such as GCC, Clang and MSVC, and languages including C, C++, assembler, CUDA, Objective-C and Objective-C++, with support varying by compiler and language. Runtime support includes Linux, macOS and native Windows at support level A, and Windows with MSYS2 and other Unix-like platforms at level B. Direct and depend modes can avoid running the preprocessor. Remote caching is possible through adaptable storage backends, with listed helpers for HTTP, HTTPS and Redis protocols. Ccache records cache hit and miss statistics, manages cache size, supports Zstandard compression, and uses BLAKE3 and XXH3 in its hashing and corruption checks. It works with Make, CMake, Ninja and Visual Studio. It is free software under the GNU GPL version 3 or later. Its scope has limits: multi-file compilation, linking and compilations with unsupported flags fall back to the real compiler. The project also cautions that cache misses add overhead and recommends measuring typical workloads.

clcache is a free, open-source Python script for Windows builds using Microsoft Visual C++ cl.exe. It intercepts compiler calls and reuses cached object files to avoid recompiling matching work, while unsupported invocations can be passed to the real compiler. Cache keys use preprocessed source, a normalized command line, and the compiler binary’s size and modification time. Command-line controls provide statistics, cleanup, clearing, and maximum-size settings; the default limit is 1073741824 bytes (1 GiB). Object files can be compressed at levels 1 through 9, though changing compression settings requires clearing the cache. Hard-link mode requires cache and build directories on the same drive. Documentation covers Visual Studio and MSBuild integration, recommends disabling TrackFileAccess, and describes optional hash caching and memcached storage. The documented path requires /c, excludes /link and /Zi, and supports /Z7. INCLUDE and LIBPATH changes may not be detected.