Remove C++ namespace handling from glibc headers.

glibc headers include some code (not particularly consistent or
systematic) to put various declarations in C++ namespaces std and
__c99, if _GLIBCPP_USE_NAMESPACES is defined.

As noted in <https://gcc.gnu.org/ml/libstdc++/2017-03/msg00025.html>,
this macro was removed from libstdc++ in 2000.  I don't expect
compilation with such old versions of libstdc++ to work with current
glibc headers anyway (whereas old *binaries* are expected to stay
working with current glibc); this patch (which should be a no-op with
any libstdc++ version postdating that removal) removes all this code
from the glibc headers.

The begin-end-check.pl test, whose comments say it is about checking
these namespace macro calls, is also removed.  The code in that test
would have covered __BEGIN_DECLS / __END_DECLS as well, but if those
weren't properly matched it would show up with the
check-installed-headers-cxx tests, so I don't think there is an actual
use for keeping begin-end-check.pl with the namespace code removed.

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by the patch).

	* misc/sys/cdefs.h (__BEGIN_NAMESPACE_STD): Remove macro.
	(__END_NAMESPACE_STD): Likewise.
	(__USING_NAMESPACE_STD): Likewise.
	(__BEGIN_NAMESPACE_C99): Likewise.
	(__END_NAMESPACE_C99): Likewise.
	(__USING_NAMESPACE_C99): Likewise.
	* math/math.h (_Mdouble_BEGIN_NAMESPACE): Do not define and
	undefine macro.
	(_Mdouble_END_NAMESPACE): Likewise.
	* ctype/ctype.h: Do not handle C++ namespaces.
	* libio/bits/stdio-ldbl.h: Likewise.
	* libio/stdio.h: Likewise.
	* locale/locale.h: Likewise.
	* math/bits/mathcalls.h: Likewise.
	* setjmp/setjmp.h: Likewise.
	* signal/signal.h: Likewise.
	* stdlib/bits/stdlib-float.h: Likewise.
	* stdlib/bits/stdlib-ldbl.h: Likewise.
	* stdlib/stdlib.h: Likewise.
	* string/string.h: Likewise.
	* sysdeps/x86/fpu/bits/mathinline.h: Likewise.
	* time/bits/types/clock_t.h: Likewise.
	* time/bits/types/struct_tm.h: Likewise.
	* time/bits/types/time_t.h: Likewise.
	* time/time.h: Likewise.
	* wcsmbs/bits/wchar-ldbl.h: Likewise.
	* wcsmbs/uchar.h: Likewise.
	* wcsmbs/wchar.h: Likewise.
	[_GLIBCPP_USE_NAMESPACES] (wint_t): Remove conditional definition.
	* wctype/wctype.h: Do not handle C++ namespaces.
	* scripts/begin-end-check.pl: Remove.
	* Makefile (installed-headers): Likewise.
	(tests-special): Do not add $(objpfx)begin-end-check.out.
	($(objpfx)begin-end-check.out): Remove.

1 files changed, 0 insertions, 6 deletions

diff --git a/signal/signal.h b/signal/signal.h
index 2c7f9e1043..84f2a1f11e 100644
--- a/signal/signal.h
+++ b/signal/signal.h
@@ -36,9 +36,7 @@ __BEGIN_DECLS
 #if defined __need_sig_atomic_t || defined _SIGNAL_H
 # ifndef __sig_atomic_t_defined
 #  define __sig_atomic_t_defined
-__BEGIN_NAMESPACE_STD
 typedef __sig_atomic_t sig_atomic_t;
-__END_NAMESPACE_STD
 # endif
 # undef __need_sig_atomic_t
 #endif
@@ -96,7 +94,6 @@ extern __sighandler_t sysv_signal (int __sig, __sighandler_t __handler)
 /* Set the handler for the signal SIG to HANDLER, returning the old
    handler, or SIG_ERR on error.
    By default `signal' has the BSD semantic.  */
-__BEGIN_NAMESPACE_STD
 #ifdef __USE_MISC
 extern __sighandler_t signal (int __sig, __sighandler_t __handler)
      __THROW;
@@ -110,7 +107,6 @@ extern __sighandler_t __REDIRECT_NTH (signal,
 #  define signal __sysv_signal
 # endif
 #endif
-__END_NAMESPACE_STD
 
 #ifdef __USE_XOPEN
 /* The X/Open definition of `signal' conflicts with the BSD version.
@@ -133,10 +129,8 @@ extern int kill (__pid_t __pid, int __sig) __THROW;
 extern int killpg (__pid_t __pgrp, int __sig) __THROW;
 #endif /* Use misc || X/Open Unix.  */
 
-__BEGIN_NAMESPACE_STD
 /* Raise signal SIG, i.e., send SIG to yourself.  */
 extern int raise (int __sig) __THROW;
-__END_NAMESPACE_STD
 
 #ifdef __USE_MISC
 /* SVID names for the same things.  */