We don't know, because GCC does not execute as a Python program. This wasn't testing the speed of compiling a program as C++ versus compiling it as C; it was t

We don't know, because GCC does not execute as a Python program. This wasn't testing the speed of compiling a program as C++ versus compiling it as C; it was testing the speed of compiling the Linux kernel using GCC-compiled-as-C++ as the compiler versus using GCC-compiled-as-C as the compiler. (And it concluded that the difference was insignificant anyway!)