Re: c++/3518: [2003-05-03] default conversion applied too soon

Re: c++/3518: [2003-05-03] default conversion applied too soon

[giovannibajo]

Old Synopsis: [2003-01-02] default conversion applied too soon
New Synopsis: [2003-05-03] default conversion applied too soon

State-Changed-From-To: analyzed->feedback
State-Changed-By: bajo
State-Changed-When: Thu May 15 11:00:10 2003
State-Changed-Why:
    Nathan, I see what you are saying but I think the code is
    still legal. The applicable ctor is attempting to create
    a const qualified _reference_ to function type, which is
    a valid type. In fact, other compilers like Comeau/EDG
    instanciate the constructor with [T = void(void)]. 
    GCC compiles the code, but applies the default conversion
    too soon, so instanciates the template with [T = (void)(*)(void)]
    which is wrong. If you agree, we can rework a code snippet
    which fails if T is a function pointer so that we can
    properly detect the bug.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=3518

Re: c++/3518: [2003-05-03] default conversion applied too soon

[Nathan Sidwell]

The following reply was made to PR c++/3518; it has been noted by GNATS.

From: Nathan Sidwell <nathan@codesourcery.com>
To: giovannibajo@libero.it, gcc-bugs@gcc.gnu.org, nathan@codesourcery.com,
   nobody@gcc.gnu.org, gcc-gnats@gcc.gnu.org
Cc:  
Subject: Re: c++/3518: [2003-05-03] default conversion applied too soon
Date: Thu, 15 May 2003 12:23:46 +0100

 giovannibajo@libero.it wrote:
 > Old Synopsis: [2003-01-02] default conversion applied too soon
 > New Synopsis: [2003-05-03] default conversion applied too soon
 > 
 > State-Changed-From-To: analyzed->feedback
 > State-Changed-By: bajo
 > State-Changed-When: Thu May 15 11:00:10 2003
 > State-Changed-Why:
 >     Nathan, I see what you are saying but I think the code is
 >     still legal. The applicable ctor is attempting to create
 >     a const qualified _reference_ to function type, which is
 >     a valid type. In fact, other compilers like Comeau/EDG
 >     instanciate the constructor with [T = void(void)]. 
 >     GCC compiles the code, but applies the default conversion
 >     too soon, so instanciates the template with [T = (void)(*)(void)]
 >     which is wrong. If you agree, we can rework a code snippet
 >     which fails if T is a function pointer so that we can
 >     properly detect the bug.
 sure. Thre are two other issues that gcc might not
 have got right then.
 1) you can ignore the cv qualifier on a reference when that reference
 is introduced by a typedef or template type parm
 2) DR 295 made the same change for function types
 
 nathan
 
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