Update copyright dates with scripts/update-copyrights

I used these shell commands:

../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")

and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 6694 files FOO.
I then removed trailing white space from benchtests/bench-pthread-locks.c
and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this
diagnostic from Savannah:
remote: *** pre-commit check failed ...
remote: *** error: lines with trailing whitespace found
remote: error: hook declined to update refs/heads/master

74 files changed, 74 insertions, 74 deletions

diff --git a/bits/byteswap.h b/bits/byteswap.h
index ccf613a9f6..6438a8b389 100644
--- a/bits/byteswap.h
+++ b/bits/byteswap.h
@@ -1,5 +1,5 @@
 /* Macros and inline functions to swap the order of bytes in integer values.
-   Copyright (C) 1997-2020 Free Software Foundation, Inc.
+   Copyright (C) 1997-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/confname.h b/bits/confname.h
index 5dc8215093..8068bda273 100644
--- a/bits/confname.h
+++ b/bits/confname.h
@@ -1,5 +1,5 @@
 /* `sysconf', `pathconf', and `confstr' NAME values.  Generic version.
-   Copyright (C) 1993-2020 Free Software Foundation, Inc.
+   Copyright (C) 1993-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/dirent.h b/bits/dirent.h
index d102c446c2..f8e8287ee9 100644
--- a/bits/dirent.h
+++ b/bits/dirent.h
@@ -1,5 +1,5 @@
 /* Directory entry structure `struct dirent'.  4.4BSD/Generic version.
-   Copyright (C) 1996-2020 Free Software Foundation, Inc.
+   Copyright (C) 1996-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/dirent_ext.h b/bits/dirent_ext.h
index 6e472f54c6..bc9dba68cd 100644
--- a/bits/dirent_ext.h
+++ b/bits/dirent_ext.h
@@ -1,5 +1,5 @@
 /* System-specific extensions of <dirent.h>, generic version.
-   Copyright (C) 2019-2020 Free Software Foundation, Inc.
+   Copyright (C) 2019-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/dlfcn.h b/bits/dlfcn.h
index ed67f29bc3..f3bc63e958 100644
--- a/bits/dlfcn.h
+++ b/bits/dlfcn.h
@@ -1,5 +1,5 @@
 /* System dependent definitions for run-time dynamic loading.
-   Copyright (C) 1996-2020 Free Software Foundation, Inc.
+   Copyright (C) 1996-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/environments.h b/bits/environments.h
index 5f39f324ae..7049784c2f 100644
--- a/bits/environments.h
+++ b/bits/environments.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1999-2020 Free Software Foundation, Inc.
+/* Copyright (C) 1999-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/errno.h b/bits/errno.h
index 663570adac..f7c0f59632 100644
--- a/bits/errno.h
+++ b/bits/errno.h
@@ -1,5 +1,5 @@
 /* Error constants.  Generic version.
-   Copyright (C) 1991-2020 Free Software Foundation, Inc.
+   Copyright (C) 1991-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/fcntl.h b/bits/fcntl.h
index a8278242e5..298e95db16 100644
--- a/bits/fcntl.h
+++ b/bits/fcntl.h
@@ -1,5 +1,5 @@
 /* O_*, F_*, FD_* bit values. 4.4BSD/Generic version.
-   Copyright (C) 1991-2020 Free Software Foundation, Inc.
+   Copyright (C) 1991-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/fenv.h b/bits/fenv.h
index 331e6c145e..399ceeba4b 100644
--- a/bits/fenv.h
+++ b/bits/fenv.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 1997-2020 Free Software Foundation, Inc.
+/* Copyright (C) 1997-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/floatn-common.h b/bits/floatn-common.h
index 6aa5ba12e4..b43c9532d8 100644
--- a/bits/floatn-common.h
+++ b/bits/floatn-common.h
@@ -1,6 +1,6 @@
 /* Macros to control TS 18661-3 glibc features where the same
    definitions are appropriate for all platforms.
-   Copyright (C) 2017-2020 Free Software Foundation, Inc.
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/floatn.h b/bits/floatn.h
index 7ac5596e2d..e83e9bb3fc 100644
--- a/bits/floatn.h
+++ b/bits/floatn.h
@@ -1,5 +1,5 @@
 /* Macros to control TS 18661-3 glibc features.
-   Copyright (C) 2017-2020 Free Software Foundation, Inc.
+   Copyright (C) 2017-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/flt-eval-method.h b/bits/flt-eval-method.h
index e2b10e3356..615e14c408 100644
--- a/bits/flt-eval-method.h
+++ b/bits/flt-eval-method.h
@@ -1,5 +1,5 @@
 /* Define __GLIBC_FLT_EVAL_METHOD.
-   Copyright (C) 2016-2020 Free Software Foundation, Inc.
+   Copyright (C) 2016-2021 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
diff --git a/bits/fp-fast.h b/bits/fp-fast.h
index 328d223027..323fcece8d 100644
--- a/bits/fp-fast.h
+++ b/bits/fp-fast.h
@@ -1,5 +1,5 @@
 /* Def