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Questions and Answers
(1) What is the goal of Embedded C++?
The goal of EC++ is to provide embedded systems programmers with a subset of C++ that is easy for the average C programmer to understand and use. The subset should offer upward compatibility with ISO/ANSI Standard C++ and retain the major advantages of C++.
To achieve the goal, several guidelines were established for creating the subset such as avoiding excessive memory consumption (overhead) and removing complex features. For detail of these guidelines, please refer the rationale page.
Questions about language specification
(1) Where is EC++ language specification?
You can find current language specification for EC++ at the page of "The Language Specification".
This specification is in the style of amendment for ISO/ANSI C++ Draft Standard which is registered as SC22/WG21/N1037.
(2) Is there any features added specially for embedded program?
No at all. EC++ specification is a pure subset of ISO/ANSI C++.
(3) Why is 'namespace' eliminated?
Though 'namespace' has no runtime overhead, it is too new to be used widely.
(4) Why is 'using' eliminated?
Though 'using' has no runtime overhead, it is too new to be used widely.
(5) Why are 'static_cast', 'reinterpret_cast', 'const_cast' eliminated?
Though such casts have no runtime overhead, it is too new to be used widely.
(6) Why is 'template' eliminated?
Currently 'template' implementation requires large memory and causes runtime overhaed.
(7) Why is RTTI eliminated?
RTTI features causes runtime overhead even if it is not actually used.
(8) Why is exception eliminated?
It is very difficult to estimate machine cycles for exception handling.
This is not suitable for embedded programs.
(9) Can I use STL?
No, you cannot.
(10) Is there any difference between EC++ and cfront?
Basically, EC++ is very similar to cfront 1.2. But EC++ specification is pure subset of ISO/ANSI C++.
(1) When will commercial level products be available?
We would say the following companies are working with Embedded C++ development:
Toshiba, Hitachi, Fujitsu, NEC, Cygnus, Green Hills, Edison, IAR and several European companies.
If your have any announcement on your EC++ product or development, please inform us of it. We are happy to list it in our web and link to your web site.
(2) Is there any official system to certificate EC++ implementation ?
(3) How is the Embedded C++ Technical Committee organized (membership)?
The Embedded C++ Technical Committee is organized by 'member', 'advisor' and 'observer'. The 'member' is to do voluntary work and have to attend regular meeting in JAPAN. The 'advisor' is to technically advise the Embedded C++ Technical Committee as so requested by the committee. Anyone who has an interrest in and supports EC++ activities can be 'observer'. Public mailing reflector for observers will be managed by the committee.
(4) Where can I get the ISO/ANSI C++ Standard?
You can refer "comp.std.c++ frequently asked questions" page.
(5) How much can I expect improvement of performance when I use EC++?
The performance (efficiency) is heavily varied depending on actual application and compiler/library implementation. There is no way other than compiling your application by actual implementation to know performance.