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, 47 deletions

diff --git a/scripts/begin-end-check.pl b/scripts/begin-end-check.pl
deleted file mode 100644
index 1616931bb0..0000000000
--- a/scripts/begin-end-check.pl
+++ /dev/null
@@ -1,47 +0,0 @@
-#!/usr/bin/perl
-
-use strict;
-use warnings;
-
-# Check __BEGIN_NAMESPACE ... __END_NAMESPACE pairing in an include file.
-
-my $code = 0;
-for my $path (@ARGV) {
-    my $localcode = 0;
-    my @stack;
-
-    open my $in, '<', $path
-        or die "open $path failed: $!";
-
-    while (<$in>) {
-        if ( /^\s*__BEGIN_(.*)\b/ ) {
-            push @stack, $1;
-        }
-        elsif ( /^\s*__END_(.*)\b/ ) {
-            if (@stack) {
-                my $tag = pop @stack;
-		if ($1 ne $tag) {
-                    print "$path:$.: BEGIN $tag paired with END $1\n";
-		    $localcode = 1;
-		}
-            }
-            else {
-                print "$path:$.: END $1 does not match a begin\n";
-		$localcode = 1;
-            }
-        }
-    }
-
-    if (@stack) {
-	print "$path: Unmatched begin tags " . join (' ', @stack) ."\n";
-	$localcode = 1;
-    }
-
-    if ($localcode == 0) {
-	print "$path: OK\n";
-    } else {
-	$code = $localcode;
-    }
-}
-
-exit $code;