Fedora 35 may use LLVM Clang to build more software

Now Fedora Linux mainly uses GCC as the default system compiler, unless there is a special situation that upstream projects only support LLVM/Clang. However, developers who package software on Fedora can decide for themselves to use LLVM Clang to build a specific package if it is worthwhile.

Recently, the manager of LLVM, Jeff Law and Tom Stellard have made a new change in the compiler policy for Fedora 35. The proposal allows developers to choose Clang to build their packages, even if the upstream project supports GCC. At the same time, even if the upstream project does not support the GNU Compiler Collection, the proposal allows GCC to be used to build software packages. For a particular software package, the decision on which compiler to use will be left to the developers in this proposal, allowing them to use their own technical judgment.

This proposal will keep GCC as the default system compiler, but those who want to use LLVM Clang, they can choose to build code faster and more optimally under LLVM/Clang. For some specific workloads, compared with GCC, using LLVM/Clang can achieve better runtime performance. This is similar to Intel’s Clear Linux which will selectively use GCC or Clang according to specific software packages to provide better performance. In addition, there are some security features and other compiler features that are also important factors that some developers are interested in LLVM.