libstdc++/8399: sync_with_stdio(false) breaks unformatted input

[marc-oliver.gewaltig@hre-ftr.f.rd.honda.co.jp]

>Number:         8399
>Category:       libstdc++
>Synopsis:       sync_with_stdio(false) breaks unformatted input
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Oct 30 02:26:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     marc-oliver.gewaltig@hre-ftr.f.rd.honda.co.jp
>Release:        gcc 3.1, gcc 3.2
>Organization:
>Environment:
Solaris 8, Suse Linux 8.0, and probably all others
>Description:
Unformatted input breaks if synchronisation with stdio
is set to false:
istream members
char get()
get(char &)
read(char *, size_t)
will only return on EOF and SIGINT
>How-To-Repeat:
Compile and start the program.
1. the prompt will appear once and get will
   never return. Same applies to other flavours of get
   and read. I did not test getline though.
2.  If sync_with_stdio(false) is removed, the program
   works as expected and shows a prompt after each <RETURN>
>Fix:

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