c++/6257: C-library symbols enter global namespace

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

>Number:         6257
>Category:       c++
>Synopsis:       C-library symbols enter global namespace
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Apr 11 09:26:00 PDT 2002
>Closed-Date:
>Last-Modified:
>Originator:     marc-oliver.gewaltig@hre-ftr.f.rd.honda.co.jp
>Release:        unknown-1.0
>Organization:
>Environment:
Linux (Suse 6.2), Solaris 8, probably all
>Description:
The C++ standard states that 
- all C++ header files define their symbols in namespace std
- all C header files, used in the form <c*> define their symbol in
  namespace std (Annex D 5.2,3).

However, g++ puts C symbols in the global namespace,
even if included via <c**> headers.

>How-To-Repeat:
The following version of hello-world should NOT compile
with an ISO-14882 compliant compiler

#include <cstdio>

int main()
{
  // should not work, because printf is in std::
  printf("Hello world.\n");

  return 0;
}
>Fix:
Put all C symbols in the namespace std, if included
by <c*> headers.
>Release-Note:
>Audit-Trail:
>Unformatted: