This incorporates:
2020-08-11 Use expression statements also on clang
2020-08-10 Use many __attribute__s with clang
2020-08-09 Use attribute __aligned__ with clang
2020-08-09 Use __alignof__ with clang
2020-08-09 ignore-value: Simplify on clang
2020-08-09 Use __typeof__ with clang
2020-08-09 intprops: Fix typo in comment
2020-08-09 Silence warnings from clang 10 with -Wimplicit-fallthrough
2020-08-09 count-one-bits: Use __builtin_popcount{,l,ll} on clang
2020-08-09 string: Fix build error in C++ mode with clang
2020-08-09 Add ability to emit user-defined diagnostics with clang
2020-08-07 alloca: No need to compile alloca.c with clang
2020-08-06 Use __builtin_assume with clang
* lib/alloca.in.h, lib/arg-nonnull.h, lib/c++defs.h, lib/cdefs.h:
* lib/count-one-bits.h, lib/dirent.in.h, lib/ignore-value.h:
* lib/intprops.h, lib/malloca.h, lib/regex_internal.h:
* lib/stdalign.in.h, lib/stddef.in.h, lib/stdio.in.h:
* lib/stdlib.in.h, lib/string.in.h, lib/verify.h, lib/warn-on-use.h:
* m4/gnulib-common.m4, m4/stddef_h.m4, m4/stdint.m4:
Copy from Gnulib.

This incorporates:
2020-06-27 getloadavg: don’t depend on fopen-gnu
2020-06-25 c-dtoastr, c-ldtoastr: new modules
2020-06-01 getloadavg: fix double-increment bug
2020-06-01 tempname: use getrandom, not getentropy
2020-05-31 tempname: merge from glibc and coreutils
2020-05-31 getentropy: work around a macOS and Solaris problem
2020-05-31 fnmatch: merge from glibc
2020-05-30 unistd: remove conflicting declaration of getrandom
2020-05-30 don't assume that UNICODE is not defined
2020-05-29 fix compilation error on native Windows
2020-05-28 avoid dynamic loading of Windows API functions when possible
2020-05-28 at-internal: make more robust in multithreaded applications
2020-05-28 getloadavg: make more robust in multithreaded applications
2020-05-27 getloadavg: make more robust in multithreaded applications
2020-05-26 count-one-bits: fix MSVC specific code
2020-05-25 getentropy, getrandom: new modules
2020-05-24 open, openat: really support O_CLOEXEC
2020-05-23 verify: document ‘assume’ better
2020-05-21 regex: configure better with "clang -fsanitize=leak"
2020-05-21 memmem: configure better with "clang -fsanitize=undefined"
2020-05-19 ftoastr: fix ifndef typo
* build-aux/config.guess, build-aux/config.sub, doc/misc/texinfo.tex:
* lib/count-one-bits.h, lib/ftoastr.c, lib/ftoastr.h:
* lib/getloadavg.c, lib/gettimeofday.c, lib/libc-config.h:
* lib/open.c, lib/openat-proc.c, lib/tempname.c, lib/tempname.h:
* lib/unistd.in.h, lib/verify.h, m4/memmem.m4, m4/regex.m4:
* m4/unistd_h.m4:
Update from Gnulib.
* lib/getrandom.c, lib/sys_random.in.h:
* m4/getrandom.m4, m4/sys_random_h.m4:
New files, copied from Gnulib.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.

This incorporates:
2020-02-21 largefile: remove _DARWIN_USE_64_BIT_INODE
2020-02-21 Add ‘extern "C"’ to count-one-bits.h etc.
* lib/count-leading-zeros.h, lib/count-one-bits.h:
* lib/count-trailing-zeros.h, m4/largefile.m4: Copy from Gnulib.

This incorporates:
2019-12-23 mktime, nstrftime: tweak division performance
2019-12-22 count-leading-zeros: assume 'long long'
2019-12-22 count-one-bits: assume 'long long'
2019-12-22 count-trailing-zeros: assume 'long long'
2019-12-12 inttypes-incomplete: assume 'long long'
2019-12-22 malloca: assume 'long long'
2019-12-22 stdint: assume 'long long'
2019-12-22 strtoll, strtoimax, strtoumax: assume 'long long'
2019-12-22 prefer lib_SOURCES to unconditional AC_LIBOBJ
2019-12-19 nstrftime: avoid a shadowing warning
2019-12-18 improve port of AC_C_RESTRICT to Oracle C++
2019-12-12 stdalign: port to xlclang 16.01
2019-12-11 stddef, unistd: fix compilation error in C++ mode on MSVC
2019-12-08 fix compilation errors in C++ mode on Haiku
2019-12-08 fix compilation errors in 32-bit C++ mode on HP-UX 11/ia64
2019-12-08 fix compilation error in C++ mode on OpenBSD
* build-aux/config.guess, doc/misc/texinfo.tex:
* lib/count-leading-zeros.h, lib/count-one-bits.h:
* lib/count-trailing-zeros.h, lib/inttypes.in.h, lib/malloca.h:
* lib/mktime.c, lib/nstrftime.c, lib/signal.in.h, lib/stdalign.in.h:
* lib/stddef.in.h, lib/stdint.in.h, lib/stdio.in.h, lib/stdlib.in.h:
* lib/strtoimax.c, lib/unistd.in.h, m4/gnulib-common.m4:
* m4/inttypes.m4, m4/largefile.m4, m4/malloca.m4, m4/strtoimax.m4:
* m4/strtoll.m4:
Copy from Gnulib.  Also, change copyright notices in some other
Gnulib-copied files to exactly match Gnulib, as Gnulib updated
them in a trivially different way.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.

Run "TZ=UTC0 admin/update-copyright $(git ls-files)".

Run 'TZ=UTC0 admin/update-copyright $(git ls-files)'.

This incorporates:
2018-01-01 maint: Run 'make update-copyright'
2017-12-29 Add cross-compilation results for GNU/Hurd.
2017-12-12 explicit_bzero: port to macOS + Clang 9.0.0

This incorporates:
2017-09-13 all: prefer https: URLs
This just changes http: to https: in comments,
in files copied from Gnulib.

Run admin/update-copyright.

This mostly just updates copyright dates of gnulib files.
It also updates to the latest version of texinfo.tex.