c/4850: GCC should implement pragma redefine_extname bind

[Martin von Loewis <loewis at informatik dot hu-berlin dot de>]

>Number:         4850
>Category:       c
>Synopsis:       GCC should implement pragma redefine_extname bind
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Sat Nov 10 07:26:00 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Martin v. Loewis <loewis@informatik.hu-berlin.de
>Release:        3.0.2 20011014 (prerelease)
>Organization:
>Environment:
System: SunOS pandora 5.8 Generic_108528-06 sun4u sparc SUNW,Ultra-Enterprise
Architecture: sun4

host: sparc-sun-solaris2.8
build: sparc-sun-solaris2.8
target: sparc-sun-solaris2.8
configured with: ../configure --enable-shared --enable-threads --with-cpu=v8 --with-gnu-ld --with-gnu-as --enable-version-specific-runtime-libs
>Description:
	In Solaris 8, Sun uses a pragma to rename symbols in a number of 
    system headers. E.g. sys/socket.h contains
#ifdef  _XPG4_2
#ifdef  __PRAGMA_REDEFINE_EXTNAME
#pragma redefine_extname bind __xnet_bind
#pragma redefine_extname connect __xnet_connect
#pragma redefine_extname recvmsg __xnet_recvmsg
#pragma redefine_extname sendmsg __xnet_sendmsg
#pragma redefine_extname sendto __xnet_sendto
#pragma redefine_extname socket __xnet_socket
#pragma redefine_extname socketpair __xnet_socketpair
#pragma redefine_extname getsockopt __xnet_getsockopt
#else   /* __PRAGMA_REDEFINE_EXTNAME */
#define bind    __xnet_bind
#define connect __xnet_connect
#define recvmsg __xnet_recvmsg
#define sendmsg __xnet_sendmsg
#define sendto  __xnet_sendto
#define socket  __xnet_socket
#define socketpair      __xnet_socketpair
#define getsockopt      __xnet_getsockopt
#endif  /* __PRAGMA_REDEFINE_EXTNAME */

#endif  /* _XPG4_2 */

	When compiling this header, in particular with g++, the macro definition
	may cause problems. These problems could be avoided if either g++
   implemented redefine_extname, or else if all those headers would be
   fixincluded.

>How-To-Repeat:
	Compile the following on Solaris 8 with g++ 3:

namespace foo{
  int socket = 1;
}

#include <sys/socket.h>

int main()
{
  foo::socket = 2;
}
    This fails with the error
    a.cc:9: `__xnet_socket' undeclared in namespace `foo'

    Part of the problem is that g++ 3 indirectly defines _XPG4_2.
>Fix:
	The work-around is to manually delete all the redefine sections in
    the g++ headers. As a drawback, the redefining does not happen in
    this approach.
>Release-Note:
>Audit-Trail:
>Unformatted: