Zapcc bests Clang in compilation, its creator says Credit: Marc-Olivier Jodoin Zapcc, a caching C++ compiler built for speed, has gone open source. Ceemple Software, Zapcc’s builder, claims the compiler offers dramatic improvements in both incremental and full builds compared to building with Clang 4.0 and Clang 5.0. Based on heavily modified code from the Clang compiler project, Zapcc uses an in-memory compilation cache in a client-server architecture. All compilation information is remembered between runs. Zapcc works in an existing build and ignores precompiled headers, an approach that requires a project be built to precise headers rules. Precompiled headers also do not cache to the same extent as Zapcc. C++ modules are not standard, are rarely used, and do not support legacy code or C++ macros well, Ceemple said. C++ modules also require significant refactoring or they are slow. Zapcc is compatible with the Gnu Compiler Collection (GCC) to the extent that Clang is GCC-compatible. Zapcc’s command syntax is identical to Clang as well, with the command being zapcc. Zapcc supports only Linux x64. Experimental support is offered for Windows x64 with mingw-w64, which provides GCC for Windows. Where to download Zapcc You can download Zapcc from its GitHub repo. C++Development ToolsSoftware DevelopmentOpen Source