Re: Suggested FAQ entry

Re: Suggested FAQ entry

[Gabriel Dos Reis]

Doug Semler <doug@seaspace.com> writes:

| This should probably be a FAQ entry, we wasted eight man hours tracking 
| this problem down, and AFAICT it isn't anywhere to be found in the docs or
| the FAQ, if I missed it, please tell me :)...
| 
| Problem:

[...]

| Solution:
|   Make sure there exists a definition for all virtual functions
|   declared in the header file - especially the first one declared (and not
|   defined in the class declaration) - even if the functions are never used.

This belongs to C++ per se, not EGCS. Doesn't it?

-- Gaby

Re: Suggested FAQ entry

[Doug Semler]

> Doug Semler <doug@seaspace.com> writes:
> 
> | This should probably be a FAQ entry, we wasted eight man hours tracking 
> | this problem down, and AFAICT it isn't anywhere to be found in the docs or
> | the FAQ, if I missed it, please tell me :)...
> | 
> | Problem:
> 
> [...]
> 
> | Solution:
> |   Make sure there exists a definition for all virtual functions
> |   declared in the header file - especially the first one declared (and not
> |   defined in the class declaration) - even if the functions are never used.
> 
> This belongs to C++ per se, not EGCS. Doesn't it?

Why?  This is an implementation issue, not a language issue...isn't it?

---
Doug Semler                       | doug@seaspace.com
SeaSpace Corporation              | Garbage In -- Gospel Out
Least Senior Software Developer;  | Minister of things to do Next Quarter
Low Man on the Totem Pole         | (but will Never Be Done) DNRC  O-
A closed mind is a terrible thing | Bus Error (passengers dumped)
  
-----BEGIN GEEK CODE BLOCK-----
Version: 3.12
GCS/M d---(pu) s++:- a-- C++ UILSH+++$ P--- L++ E--- W+
N++ o-- K? w--(++$) O- M-- V- PS+ !PE Y PGP t(+) 5+++ X+
R- tv+(-) b+(++) DI++++ D G e++>++++ h!>--- r% y+>+++++**
------END GEEK CODE BLOCK------

Re: Suggested FAQ entry

[Gabriel Dos Reis]

Doug Semler <doug@seaspace.com> writes:


[...]

| > | Solution:
| > |   Make sure there exists a definition for all virtual functions
| > |   declared in the header file - especially the first one declared (and not
| > |   defined in the class declaration) - even if the functions are never used.
| > 
| > This belongs to C++ per se, not EGCS. Doesn't it?
| 
| Why?  This is an implementation issue, not a language issue...isn't it?

No. The definition of ISO C++ require you do define all virtual
functions -- unless they are pure -- even if you seem not using them
explicitly: from C++ point of view, they are always used. 

-- Gaby