libstdc++/5627: cstdio header failes to compile on sparc-sun-solaris2.7 with _FILE_OFFSET_BITS == 64

[paulf@sea.checkpoint.com]

>Number:         5627
>Category:       libstdc++
>Synopsis:       cstdio header failes to compile on sparc-sun-solaris2.7 with _FILE_OFFSET_BITS == 64
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          rejects-legal
>Submitter-Id:   net
>Arrival-Date:   Thu Feb 07 13:16:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Paul Forgey
>Release:        gcc version 2.95.2 19991024 (release)
>Organization:
>Environment:
sparc-sun-solaris2.7
>Description:
when _FILE_OFFSET_BITS is set to `64', the system's stdio.h will actually make the symbols fopen, freopen, tmpfile, fgetpos and fsetpos unavailable at all, even as normal function definitions, if they are #undef'd.  This causes the later part of the header file pulling these into namespace std to fail with complaints these symbols are undefined.
>How-To-Repeat:
attempt to build Berkeley db-3.3.11 after passing --enable-cxx to the configure script.
>Fix:
This is probably not the best fix, but it got me past the issue.  Somebody who knows their way around the solaris headers better than I do could probably come up with a more "real" fix:

in $prefix/include/g++-v3/bits/std_cstdio.h, remove the #undef macros for these symbols, and add the following code at line 43 (right after #include <stdio.h>):

// The following functions _can not_ be #undef'd if we are using 64
// bit file pointers
#if ! (defined (sun) && !defined (_LP64) && _FILE_OFFSET_BITS == 64)

#undef fopen
#undef freopen
#undef tmpfile
#undef fgetpos
#undef fsetpos

#endif // whew

>Release-Note:
>Audit-Trail:
>Unformatted: