libstdc++/4886: Solaris largefile support for fopen removed by include/g++-v3/bits/std_cstdio.h

[alex@softgrow.com]

>Number:         4886
>Category:       libstdc++
>Synopsis:       Solaris largefile support for fopen removed by include/g++-v3/bits/std_cstdio.h
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Nov 15 16:56:00 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Wilf Kruggel
>Release:        unknown-1.0
>Organization:
>Environment:
Solaris 8.0 
gcc 3.0.2
>Description:
When compiling on Solaris for files > 2 Gigs the flag -D_FILE_OFFSET_BITS=64 and -D_LARGEFILE_SOURCE cause the Solaris supplied /usr/include/stdio.h to create define fopen as fopen64 using a macro.
This macro is undefined by the gcc include/g++-v3/bits/.std_cstdio.h
Thus any attempt to open a largefile in compiled code will fail on execution with an error "Value too large for defined data type". Truss will show fopen being called rather than fopen64.
>How-To-Repeat:
Try the following code on a large file > 2 Gigs
g++ `LFS_CLFAGS` -o junk junk.c 
#include <cstdio>

main()
{
  FILE *fp = fopen("reallybigfile.gen","rb");
  if (fp==NULL) perror("fopen");
}
You will get when you run 
fopen: Value too large for defined data type
>Fix:
remove "#undef fopen" (and same for fgetpos, freopen, fsetpos) in std_cstdio.h but this may break something else. 
>Release-Note:
>Audit-Trail:
>Unformatted: