Re: [CEDET-devel] Bug in semantic-c.el with define-mode-local-override definitions

[David P. <dav...@wa...>]

Klaus,

> ok, point is taken - means seems no bug with defining the overload for
> c-mode...

Good ;-)

> But nevertheless something doesn't work:
> 
> here is what is done by semantic-tag-abstract-p-c-mode:
> 
>    ((eq (semantic-tag-class tag) 'function)
>     (semantic-tag-get-attribute tag :pure-virtual-flag))
> 
> Ok, when i put point onto the virtual method "aProctedMethod"
> (line 8 in the following short c++-header-file klaus-test.hpp) then
> (semantic-tag-attributes (semantic-current-tag)) returns
> 
> (:prototype-flag t :typemodifiers ("virtual") :type "void")
> 
> You see, there is no attribute :pure-virtual-flag contained in
> the plist! So no one can be found and therefore in turn the
> abstract-p check fails...

I didn't received your klaus-test.hpp sample.  Anyway it looks you're
probably right.  The :pure-virtual-flag is provided by the c.by
grammar rule:

fun-or-proto-end
  : SEMICOLON
    ( t )
  | semantic-list
    ( nil )
 ;; Here is an anoying feature of C++ pure virtual methods
  | EQUAL ZERO SEMICOLON
    ( :pure-virtual-flag )
  ;

which seems to check that the function declaration ends with "= 0;" to
consider it as pure virtual, which looks good for me.

IMO, the problem is in the C override of `semantic-tag-abstract-p'
which doesn't check the virtual modifiers for functions.  Probably it
should be modified like this:

Index: semantic-c.el
===================================================================
RCS file: /cvsroot/cedet/cedet/semantic/bovine/semantic-c.el,v
retrieving revision 1.34
diff -c -r1.34 semantic-c.el
*** semantic-c.el	23 Jul 2004 18:37:33 -0000	1.34
--- semantic-c.el	8 Sep 2004 12:54:56 -0000
***************
*** 500,506 ****
  	       )
  	  )))
     ((eq (semantic-tag-class tag) 'function)
!     (semantic-tag-get-attribute tag :pure-virtual-flag))
     (t (semantic-tag-abstract-p-default tag parent))))
  
  (define-mode-local-override semantic-analyze-dereference-metatype
--- 500,507 ----
  	       )
  	  )))
     ((eq (semantic-tag-class tag) 'function)
!     (or (semantic-tag-get-attribute tag :pure-virtual-flag)
!         (member "virtual" (semantic-tag-modifiers tag))))
     (t (semantic-tag-abstract-p-default tag parent))))
  
  (define-mode-local-override semantic-analyze-dereference-metatype



If it looks good for you (I am not a C/C++ guru), I will commit the
change.

Thanks for your sharp eyesight!

David