I bundle and distribute GCC for an OS distribution and I can count 5 dependencies for building GCC from source (not including a host toolchain), two of which ar

I bundle and distribute GCC for an OS distribution and I can count 5 dependencies for building GCC from source (not including a host toolchain), two of which are also runtime dependencies. That means if you're installing GCC, you also need to install binutils and a C library. GCC itself, of course, bundles a number of dependencies like the gcc toolchain driver, the cc1 and cc1plus compilers, the collect2 linker front-ender, plus a number of runtime libraries both for the toolchain and for bundling into the executable. If you're targeting C++ that adds a couple more runtime dependencies which can optionally be bundled with GCC. Of course, everything also depends on the host runtime. Some OS distributions split GCC into multiple packages with interdependencies, putting for exaple the C preprocessor into a separate package from the compiler proper (which is odd, considering it's the same executable, but there are historic reasons). So, an exact number of dependencies for GCC, depending on how it gets packaged for your development host, can range from 3 to 14 or 15.