To fix the issue you can do It is compiler-specific, and depends upon the optimizations you are asking from your compiler. Most recent free software C++11 (or C++14) compilers are able to do link-time optimization : both recent GCC & Clang/LLVM are accepting the -flto flag (for link time optimiation...). To use it you should compile and link your code with it, and some additional (same) optimization flags. A typical use thru the make builder could be:
around this issue The issue with the CodeDom package is that is copies the roslyn binaries into the \bin folder of your app, and tries to execute csc.exe from there, but it doesn't have the rights to do so. The correct solution to this is to precompile your views before deploying them to the server. There are numerous existing guides on how to do that. For running StackOverflow we use StackExchange.Precompilation.