> Ugh, old, old FUD from years back (not you, the article). g++ (the only C++ compiler that's relevant) has been as fast as gcc for years (they use the same back-end).
g++'s generated code is not as fast as gcc's, despite their common infrastructure. For the last month or two, gcc has been compilable with g++ as well (it has been rewritten in the common C/C++ subset), and the reports are of about a 10% decrease in speed when compiling with g++.
In reality any C++ code can (and it's internally) translated to C one (that's called the front-end compiler). The back-end is the same.
The only difference is when there are things required by the C++ runtime (mainly exceptions and RTTI, and in some sense virtual functions).
I'm sure that if you take a "C" code, and compile it under "C++" compiler (given that it can compile) - you won't see difference.
Please disassemble it, and see for yourself.
That's the other problem with C++ - no one actually for real writes in full C++ - you always end up sacrificing features (exceptions most notably) to have running on embedded systems, or game consoles. And no RTTI there too.
For example if you have exceptions enabled, there must be some infrastructure for handling them. Certain C++ compilers generate almost no code for handling exceptions, but the handling is expensive. Other compensate that with more generated code (for keeping stack frames), and faster handling.
So you can say - well - disable the exceptions.... But is that C++ anymore?
For example Common Lisp is multi-paradigm, but there is no Common Lisp without CLOS. It can't be disabled, and still call itself Common Lisp.
Same with RTTI in C++ - it's in the language, but again it can be disabled. Or new/delete (and the missing reallocate construct).
So C++ the language, and C++ the runtime being used are quite different things when comes to usage.
g++'s generated code is not as fast as gcc's, despite their common infrastructure. For the last month or two, gcc has been compilable with g++ as well (it has been rewritten in the common C/C++ subset), and the reports are of about a 10% decrease in speed when compiling with g++.