Thread

1. ilist.h fails cpluspluscheck

   Peter Eisentraut <peter_e@gmx.net> — 2012-11-27T04:55:21Z

   In file included from ./src/include/utils/catcache.h:25:0,
                    from /tmp/cpluspluscheck.bt8VZr/test.cpp:3:
   src/include/lib/ilist.h: In function ‘dlist_node* dlist_head_node(dlist_head*)’:
   src/include/lib/ilist.h:470:39: error: invalid conversion from ‘void*’ to ‘dlist_node*’ [-fpermissive]
   src/include/lib/ilist.h: In function ‘dlist_node* dlist_tail_node(dlist_head*)’:
   src/include/lib/ilist.h:487:39: error: invalid conversion from ‘void*’ to ‘dlist_node*’ [-fpermissive]
   In file included from ./src/include/utils/catcache.h:25:0,
                    from /tmp/cpluspluscheck.bt8VZr/test.cpp:3:
   src/include/lib/ilist.h: In function ‘slist_node* slist_head_node(slist_head*)’:
   src/include/lib/ilist.h:680:39: error: invalid conversion from ‘void*’ to ‘slist_node*’ [-fpermissive]
   In file included from /tmp/cpluspluscheck.bt8VZr/test.cpp:3:0:
   ./src/include/lib/ilist.h: In function ‘dlist_node* dlist_head_node(dlist_head*)’:
   ./src/include/lib/ilist.h:470:39: error: invalid conversion from ‘void*’ to ‘dlist_node*’ [-fpermissive]
   ./src/include/lib/ilist.h: In function ‘dlist_node* dlist_tail_node(dlist_head*)’:
   ./src/include/lib/ilist.h:487:39: error: invalid conversion from ‘void*’ to ‘dlist_node*’ [-fpermissive]
   In file included from /tmp/cpluspluscheck.bt8VZr/test.cpp:3:0:
   ./src/include/lib/ilist.h: In function ‘slist_node* slist_head_node(slist_head*)’:
   ./src/include/lib/ilist.h:680:39: error: invalid conversion from ‘void*’ to ‘slist_node*’ [-fpermissive]
   
   Maybe some ifndef __cplusplus would help.
   
   
   
   
   

2. Re: ilist.h fails cpluspluscheck

   Tom Lane <tgl@sss.pgh.pa.us> — 2012-11-27T06:14:27Z

   Peter Eisentraut <peter_e@gmx.net> writes:
   > In file included from ./src/include/utils/catcache.h:25:0,
   >                  from /tmp/cpluspluscheck.bt8VZr/test.cpp:3:
   > src/include/lib/ilist.h: In function dlist_node* dlist_head_node(dlist_head*):
   > src/include/lib/ilist.h:470:39: error: invalid conversion from void* to dlist_node* [-fpermissive]
   
   > Maybe some ifndef __cplusplus would help.
   
   Or maybe we need to recommend use of -fpermissive?  If C++ thinks
   casting void * to something else is illegitimate, it's basically not
   going to cope with most things we might try to inline in Postgres.
   And I don't think that saying "you don't get to call these fundamental
   support functions from C++" is likely to fly, so just hiding the
   functions won't help much.
   
   			regards, tom lane
   
   
   

3. Re: ilist.h fails cpluspluscheck

   Andres Freund <andres@2ndquadrant.com> — 2012-11-27T09:56:51Z

   On 2012-11-27 01:14:27 -0500, Tom Lane wrote:
   > Peter Eisentraut <peter_e@gmx.net> writes:
   > > In file included from ./src/include/utils/catcache.h:25:0,
   > >                  from /tmp/cpluspluscheck.bt8VZr/test.cpp:3:
   > > src/include/lib/ilist.h: In function ‘dlist_node* dlist_head_node(dlist_head*)’:
   > > src/include/lib/ilist.h:470:39: error: invalid conversion from ‘void*’ to ‘dlist_node*’ [-fpermissive]
   >
   > > Maybe some ifndef __cplusplus would help.
   >
   > Or maybe we need to recommend use of -fpermissive?  If C++ thinks
   > casting void * to something else is illegitimate, it's basically not
   > going to cope with most things we might try to inline in Postgres.
   > And I don't think that saying "you don't get to call these fundamental
   > support functions from C++" is likely to fly, so just hiding the
   > functions won't help much.
   
   Its rather easy to fix in the ilist code at least - the cases it points
   out are those where I took a slightly ugly shortcut to reduce some very
   minor code duplication...
   
   Some casts fix it, alternatively the
   
        Assert(!dlist_is_empty());
        return head->head.next
   could be moved into [ds]list_(head|tail)_node instead of relying on the
   *_elemen_off support functions.
   
   Greetings,
   
   Andres
   
   --
    Andres Freund	                   http://www.2ndQuadrant.com/
    PostgreSQL Development, 24x7 Support, Training & Services
   

4. Re: ilist.h fails cpluspluscheck

   Tom Lane <tgl@sss.pgh.pa.us> — 2012-11-27T16:00:11Z

   Andres Freund <andres@2ndquadrant.com> writes:
   > On 2012-11-27 01:14:27 -0500, Tom Lane wrote:
   >> Peter Eisentraut <peter_e@gmx.net> writes:
   >>> Maybe some ifndef __cplusplus would help.
   
   > Its rather easy to fix in the ilist code at least - the cases it points
   > out are those where I took a slightly ugly shortcut to reduce some very
   > minor code duplication...
   
   > Some casts fix it,
   
   Seems reasonable, committed.
   
   I wonder if we could get a buildfarm member or two running
   cpluspluscheck.
   
   			regards, tom lane