I worked on a mixed C++ and C# codebase where we switched from in-process calls to IPC for that very reason, taking the efficiency hit. Having the .NET runtime

I worked on a mixed C++ and C# codebase where we switched from in-process calls to IPC for that very reason, taking the efficiency hit. Having the .NET runtime running in the same address space confused any sanitizer or leak detector. You rely on those tools to manage a large C++ codebase in practice. Also, because the .NET GC churns through a lot of memory, statistically almost every problem on the C++ turned up on the C# side first, sometimes with very confusing effects. For example, .NET has a compacting GC, so an object can get corrupted and then randomly moved somewhere else. We didn't have that kind of problem often, but when we did, it was pure hell to debug.