PR/58206 CVS commit: src

["Taylor R Campbell" <riastradh%netbsd.org@localhost>]

The following reply was made to PR lib/58206; it has been noted by GNATS.

From: "Taylor R Campbell" <riastradh%netbsd.org@localhost>
To: gnats-bugs%gnats.NetBSD.org@localhost
Cc: 
Subject: PR/58206 CVS commit: src
Date: Mon, 20 May 2024 11:20:53 +0000

 Module Name:	src
 Committed By:	riastradh
 Date:		Mon May 20 11:20:53 UTC 2024
 
 Modified Files:
 	src/external/gpl3/gcc/dist/libstdc++-v3/config/io: basic_file_stdio.cc
 	src/tests/lib/libstdc++: t_sync_with_stdio.sh
 
 Log Message:
 libstdc++: Don't try to fflush stdin.
 
 It doesn't work.  It's undefined behaviour.  On NetBSD, it will fail
 with EBADF, if fd 0 isn't open for write, or if fd 0 is open for
 write, it will write heap garbage to fd 0.
 
    If stream points to an output stream or an update stream in which
    the most recent operation was not input, the fflush function causes
    any unwritten data for that stream to be delivered to the host
    environment to be written to the file; otherwise, the behavior is
    undefined.
 
    (ISO C11 and ISO C17, Sec. 7.21.5.2 `The fflush function')
 
 PR lib/58206
 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114879
 
 
 To generate a diff of this commit:
 cvs rdiff -u -r1.1.1.13 -r1.2 \
     src/external/gpl3/gcc/dist/libstdc++-v3/config/io/basic_file_stdio.cc
 cvs rdiff -u -r1.1 -r1.2 src/tests/lib/libstdc++/t_sync_with_stdio.sh
 
 Please note that diffs are not public domain; they are subject to the
 copyright notices on the relevant files.