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Virtual functions have the same speed

Posted Jun 18, 2008 20:54 UTC (Wed) by khim (subscriber, #9252)
In reply to: Sometimes C++ is faster by johnkarp
Parent article: Converting GCC to C++

Remember - for a long, long time C++ compiler was C++-to-C compiler. Only one thing can not be efficiently implemented in C++-to-C compiler: exceptions. Everything else is just as efficient in C and in C++... except templates: where C++ compiler can generate series of functions automatically in C you either need horrible preprocessor cludges and/or code duplication.

Of course the same capability can be easily abused and lead to slower code!

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Posted Jun 19, 2008 9:48 UTC (Thu) by nix (subscriber, #2304) [Link]

For a long, long time? I think the gap was something like three years between Cfront and G++.
It might have felt like a long time then, but it really wasn't. :)

10 years is long time in computing

Posted Jun 19, 2008 14:04 UTC (Thu) by khim (subscriber, #9252) [Link]

Cfront defined C++ for almost 10 years. Between 1983 and 1993 Cfront was the C++ compiler - and a lot of limitations of C++ back then were justified by the need to compile to C. It was reference implementation, it was used to define "standard C++" (people even used versions of Cfront to explain what type of language their compiler supported), etc. Eventually Cfront 4.0 was abandoned and after long period of instability (~5years) we've got consolidated standard and language was set in stone. But yes, for a long time needs of C++-to-C compiler defined the language.