Update from Gnulib

This incorporates:
2018-05-21 crypto: omit stream ops Emacs doesn’t need
2018-05-13 truncate: Fix compilation error on Android
2018-05-13 imaxdiv: Fix compilation error on Android
2018-05-13 Support selective inclusion of recent mingw.org headers
2018-05-13 Add cross-compilation guesses for Linux systems sans glibc
2018-05-13 stdioext: Fix compilation errors with newer Android headers
2018-05-07 af_alg: Pacify --enable-gcc-warnings
2018-05-06 af_alg: Fix bug with streams that are not at position 0
2018-05-06 Followup to 'af_alg: New module'
2018-05-05 crypto/{md5,sha1,sha256,sha512}: simplify
2018-05-05 af_alg: New module
2018-05-05 af_alg: Improve function signature
2018-04-28 md5sum: Use AF_ALG when available
2018-04-28 sha512sum: Use AF_ALG when available
2018-04-28 sha256sum: Use AF_ALG when available
2018-04-28 sha1sum: Use AF_ALG when available
2018-05-05 all: Replace more http URLs by https URLs
2018-05-03 maint: port more modules to GCC 8
2018-05-03 Simplify code; drop support for Borland C++ on Windows
* admin/merge-gnulib (GNULIB_MODULES): Use crypto/md5-buffer
rather than crypto/md5, since Emacs doesn’t use the stream
operations that in recent Gnulib pull in other stuff Emacs doesn’t
need.  Similarly for crypto/sha1-buffer, crypto/sha256-buffer,
crypto/sha512-buffer.
* build-aux/config.guess, build-aux/config.sub, lib/dosname.h:
* lib/dup2.c, lib/errno.in.h, lib/euidaccess.c, lib/fcntl.c:
* lib/fcntl.in.h, lib/fpending.c, lib/fsync.c, lib/getdtablesize.c:
* lib/getopt.c, lib/gettimeofday.c, lib/inttypes.in.h, lib/md5.c:
* lib/md5.h, lib/open.c, lib/pipe2.c, lib/putenv.c, lib/sha1.c:
* lib/sha1.h, lib/sha256.c, lib/sha256.h, lib/sha512.c:
* lib/sha512.h, lib/stat-time.h, lib/stdio-impl.h, lib/stdio.in.h:
* lib/stdlib.in.h, lib/sys_stat.in.h, lib/sys_types.in.h:
* lib/timespec.h, lib/unistd.in.h, lib/utimens.c, m4/c-strtod.m4:
* m4/gnulib-common.m4, m4/inttypes.m4, m4/lstat.m4, m4/nocrash.m4:
* m4/pselect.m4, m4/readlink.m4, m4/stdio_h.m4, m4/symlink.m4:
* m4/unistd_h.m4, m4/utimens.m4:
Copy from Gnulib.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.

33 files changed, 242 insertions, 233 deletions

diff --git a/lib/dosname.h b/lib/dosname.h
index 66486d5209d..fef3b6daa1f 100644
--- a/lib/dosname.h
+++ b/lib/dosname.h
@@ -20,9 +20,8 @@
 #ifndef _DOSNAME_H
 #define _DOSNAME_H
 
-#if (defined _WIN32 || defined __WIN32__ ||     \
-     defined __MSDOS__ || defined __CYGWIN__ || \
-     defined __EMX__ || defined __DJGPP__)
+#if (defined _WIN32 || defined __CYGWIN__ \
+     || defined __EMX__ || defined __MSDOS__ || defined __DJGPP__)
    /* This internal macro assumes ASCII, but all hosts that support drive
       letters use ASCII.  */
 # define _IS_DRIVE_LETTER(C) (((unsigned int) (C) | ('a' - 'A')) - 'a'  \
diff --git a/lib/dup2.c b/lib/dup2.c
index c8b49b25e47..c7d176728d4 100644
--- a/lib/dup2.c
+++ b/lib/dup2.c
@@ -29,7 +29,7 @@
 
 # undef dup2
 
-# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+# if defined _WIN32 && ! defined __CYGWIN__
 
 /* Get declarations of the native Windows API functions.  */
 #  define WIN32_LEAN_AND_MEAN
diff --git a/lib/errno.in.h b/lib/errno.in.h
index 8d2f3074fab..b95c4e9ce76 100644
--- a/lib/errno.in.h
+++ b/lib/errno.in.h
@@ -30,7 +30,7 @@
 
 
 /* On native Windows platforms, many macros are not defined.  */
-# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+# if defined _WIN32 && ! defined __CYGWIN__
 
 /* These are the same values as defined by MSVC 10, for interoperability.  */
 
@@ -248,7 +248,7 @@
        interoperability.  */
 #   define EOWNERDEAD      58
 #   define ENOTRECOVERABLE 59
-#  elif (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#  elif defined _WIN32 && ! defined __CYGWIN__
     /* We have a conflict here: pthreads-win32 defines these values
        differently than MSVC 10.  It's hairy to decide which one to use.  */
 #   if defined __MINGW32__ && !defined USE_WINDOWS_THREADS
diff --git a/lib/euidaccess.c b/lib/euidaccess.c
index 4f512f5af54..de5d82b52d5 100644
--- a/lib/euidaccess.c
+++ b/lib/euidaccess.c
@@ -29,7 +29,7 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <unistd.h>
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
 # include <io.h>
 #else
 # include "root-uid.h"
@@ -87,7 +87,7 @@ euidaccess (const char *file, int mode)
   return accessx (file, mode, ACC_SELF);
 #elif HAVE_EACCESS                      /* FreeBSD */
   return eaccess (file, mode);
-#elif (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__  /* mingw */
+#elif defined _WIN32 && ! defined __CYGWIN__  /* mingw */
   return _access (file, mode);
 #else              /* Mac OS X, NetBSD, OpenBSD, HP-UX, Solaris, Cygwin, BeOS */
 
diff --git a/lib/fcntl.c b/lib/fcntl.c
index b8cb271f55c..be6583565b4 100644
--- a/lib/fcntl.c
+++ b/lib/fcntl.c
@@ -32,7 +32,7 @@
 #endif
 #undef fcntl
 
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
 /* Get declarations of the native Windows API functions.  */
 # define WIN32_LEAN_AND_MEAN
 # include <windows.h>
@@ -376,7 +376,7 @@ rpl_fcntl (int fd, int action, /* arg */...)
 #if !HAVE_FCNTL
     case F_GETFD:
       {
-# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+# if defined _WIN32 && ! defined __CYGWIN__
         HANDLE handle = (HANDLE) _get_osfhandle (fd);
         DWORD flags;
         if (handle == INVALID_HANDLE_VALUE
diff --git a/lib/fcntl.in.h b/lib/fcntl.in.h
index 719a54d0f72..a1e7d35c1b9 100644
--- a/lib/fcntl.in.h
+++ b/lib/fcntl.in.h
@@ -68,7 +68,7 @@
 
 /* Native Windows platforms declare open(), creat() in <io.h>.  */
 #if (@GNULIB_OPEN@ || defined GNULIB_POSIXCHECK) \
-    && ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__)
+    && (defined _WIN32 && ! defined __CYGWIN__)
 # include <io.h>
 #endif
 
diff --git a/lib/fpending.c b/lib/fpending.c
index 7bc235deda2..de370d4b10f 100644
--- a/lib/fpending.c
+++ b/lib/fpending.c
@@ -24,6 +24,9 @@
 
 #include "stdio-impl.h"
 
+/* This file is not used on systems that already have the __fpending function,
+   namely glibc >= 2.2, Solaris >= 7, Android API >= 23.  */
+
 /* Return the number of pending (aka buffered, unflushed)
    bytes on the stream, FP, that is open for writing.  */
 size_t
diff --git a/lib/fsync.c b/lib/fsync.c
index a0b12b6ccc7..ecacb0ba25e 100644
--- a/lib/fsync.c
+++ b/lib/fsync.c
@@ -25,7 +25,7 @@
 #include <config.h>
 #include <unistd.h>
 
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
 
 /* FlushFileBuffers */
 # define WIN32_LEAN_AND_MEAN
diff --git a/lib/getdtablesize.c b/lib/getdtablesize.c
index c6c1136fc55..ac05bc483cc 100644
--- a/lib/getdtablesize.c
+++ b/lib/getdtablesize.c
@@ -20,7 +20,7 @@
 /* Specification.  */
 #include <unistd.h>
 
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
 
 # include <stdio.h>
 
diff --git a/lib/getopt.c b/lib/getopt.c
index 55375ccd40f..11e36eef815 100644
--- a/lib/getopt.c
+++ b/lib/getopt.c
@@ -46,7 +46,7 @@
 /* When used standalone, flockfile and funlockfile might not be
    available.  */
 # if (!defined _POSIX_THREAD_SAFE_FUNCTIONS \
-      || ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__))
+      || (defined _WIN32 && ! defined __CYGWIN__))
 #  define flockfile(fp) /* nop */
 #  define funlockfile(fp) /* nop */
 # endif
diff --git a/lib/gettimeofday.c b/lib/gettimeofday.c
index 39575658264..d598b2f7f56 100644
--- a/lib/gettimeofday.c
+++ b/lib/gettimeofday.c
@@ -24,7 +24,7 @@
 
 #include <time.h>
 
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
 # define WINDOWS_NATIVE
 # include <windows.h>
 #endif
diff --git a/lib/gnulib.mk.in b/lib/gnulib.mk.in
index ce47b9de661..19128bab2da 100644
--- a/lib/gnulib.mk.in
+++ b/lib/gnulib.mk.in
@@ -21,7 +21,7 @@
 # the same distribution terms as the rest of that program.
 #
 # Generated by gnulib-tool.
-# Reproduce by: gnulib-tool --import --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --avoid=close --avoid=dup --avoid=fchdir --avoid=fstat --avoid=malloc-posix --avoid=msvc-inval --avoid=msvc-nothrow --avoid=openat-die --avoid=opendir --avoid=raise --avoid=save-cwd --avoid=select --avoid=setenv --avoid=sigprocmask --avoid=stat --avoid=stdarg --avoid=stdbool --avoid=threadlib --avoid=tzset --avoid=unsetenv --avoid=utime --avoid=utime-h --gnu-make --makefile-name=gnulib.mk.in --conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files alloca-opt binary-io byteswap c-ctype c-strcase careadlinkat close-stream count-leading-zeros count-one-bits count-trailing-zeros crypto/md5 crypto/sha1 crypto/sha256 crypto/sha512 d-type diffseq dtoastr dtotimespec dup2 environ execinfo explicit_bzero faccessat fcntl fcntl-h fdatasync fdopendir filemode filevercmp flexmember fstatat fsusage fsync getloadavg getopt-gnu gettime gettimeofday gitlog-to-changelog ignore-value intprops largefile lstat manywarnings memrchr minmax mkostemp mktime nstrftime pipe2 pselect pthread_sigmask putenv qcopy-acl readlink readlinkat sig2str socklen stat-time std-gnu11 stdalign stddef stdio stpcpy strtoimax symlink sys_stat sys_time tempname time time_r time_rz timegm timer-time timespec-add timespec-sub unlocked-io update-copyright utimens vla warnings
+# Reproduce by: gnulib-tool --import --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --avoid=close --avoid=dup --avoid=fchdir --avoid=fstat --avoid=malloc-posix --avoid=msvc-inval --avoid=msvc-nothrow --avoid=openat-die --avoid=opendir --avoid=raise --avoid=save-cwd --avoid=select --avoid=setenv --avoid=sigprocmask --avoid=stat --avoid=stdarg --avoid=stdbool --avoid=threadlib --avoid=tzset --avoid=unsetenv --avoid=utime --avoid=utime-h --gnu-make --makefile-name=gnulib.mk.in --conditional-dependencies --no-libtool --macro-prefix=gl --no-vc-files alloca-opt binary-io byteswap c-ctype c-strcase careadlinkat close-stream count-leading-zeros count-one-bits count-trailing-zeros crypto/md5-buffer crypto/sha1-buffer crypto/sha256-buffer crypto/sha512-buffer d-type diffseq dtoastr dtotimespec dup2 environ execinfo explicit_bzero faccessat fcntl fcntl-h fdatasync fdopendir filemode filevercmp flexmember fstatat fsusage fsync getloadavg getopt-gnu gettime gettimeofday gitlog-to-changelog ignore-value intprops largefile lstat manywarnings memrchr minmax mkostemp mktime nstrftime pipe2 pselect pthread_sigmask putenv qcopy-acl readlink readlinkat sig2str socklen stat-time std-gnu11 stdalign stddef stdio stpcpy strtoimax symlink sys_stat sys_time tempname time time_r time_rz timegm timer-time timespec-add timespec-sub unlocked-io update-copyright utimens vla warnings
 
 
 MOSTLYCLEANFILES += core *.stackdump
@@ -387,6 +387,7 @@ HAVE_DECL_STRSIGNAL = @HAVE_DECL_STRSIGNAL@
 HAVE_DECL_STRTOIMAX = @HAVE_DECL_STRTOIMAX@
 HAVE_DECL_STRTOK_R = @HAVE_DECL_STRTOK_R@
 HAVE_DECL_STRTOUMAX = @HAVE_DECL_STRTOUMAX@
+HAVE_DECL_TRUNCATE = @HAVE_DECL_TRUNCATE@
 HAVE_DECL_TTYNAME_R = @HAVE_DECL_TTYNAME_R@
 HAVE_DECL_UNSETENV = @HAVE_DECL_UNSETENV@
 HAVE_DECL_VSNPRINTF = @HAVE_DECL_VSNPRINTF@
@@ -421,6 +422,7 @@ HAVE_GETSUBOPT = @HAVE_GETSUBOPT@
 HAVE_GETTIMEOFDAY = @HAVE_GETTIMEOFDAY@
 HAVE_GRANTPT = @HAVE_GRANTPT@
 HAVE_GROUP_MEMBER = @HAVE_GROUP_MEMBER@
+HAVE_IMAXDIV_T = @HAVE_IMAXDIV_T@
 HAVE_INTTYPES_H = @HAVE_INTTYPES_H@
 HAVE_LCHMOD = @HAVE_LCHMOD@
 HAVE_LCHOWN = @HAVE_LCHOWN@
@@ -513,7 +515,6 @@ HAVE_SYS_TIME_H = @HAVE_SYS_TIME_H@
 HAVE_SYS_TYPES_H = @HAVE_SYS_TYPES_H@
 HAVE_TIMEGM = @HAVE_TIMEGM@
 HAVE_TIMEZONE_T = @HAVE_TIMEZONE_T@
-HAVE_TRUNCATE = @HAVE_TRUNCATE@
 HAVE_TYPE_VOLATILE_SIG_ATOMIC_T = @HAVE_TYPE_VOLATILE_SIG_ATOMIC_T@
 HAVE_TZSET = @HAVE_TZSET@
 HAVE_UNISTD_H = @HAVE_UNISTD_H@
@@ -1151,45 +1152,45 @@ EXTRA_DIST += count-trailing-zeros.h
 endif
 ## end   gnulib module count-trailing-zeros
 
-## begin gnulib module crypto/md5
-ifeq (,$(OMIT_GNULIB_MODULE_crypto/md5))
+## begin gnulib module crypto/md5-buffer
+ifeq (,$(OMIT_GNULIB_MODULE_crypto/md5-buffer))
 
 libgnu_a_SOURCES += md5.c
 
 EXTRA_DIST += gl_openssl.h md5.h
 
 endif
-## end   gnulib module crypto/md5
+## end   gnulib module crypto/md5-buffer
 
-## begin gnulib module crypto/sha1
-ifeq (,$(OMIT_GNULIB_MODULE_crypto/sha1))
+## begin gnulib module crypto/sha1-buffer
+ifeq (,$(OMIT_GNULIB_MODULE_crypto/sha1-buffer))
 
 libgnu_a_SOURCES += sha1.c
 
 EXTRA_DIST += gl_openssl.h sha1.h
 
 endif
-## end   gnulib module crypto/sha1
+## end   gnulib module crypto/sha1-buffer
 
-## begin gnulib module crypto/sha256
-ifeq (,$(OMIT_GNULIB_MODULE_crypto/sha256))
+## begin gnulib module crypto/sha256-buffer
+ifeq (,$(OMIT_GNULIB_MODULE_crypto/sha256-buffer))
 
 libgnu_a_SOURCES += sha256.c
 
 EXTRA_DIST += gl_openssl.h sha256.h
 
 endif
-## end   gnulib module crypto/sha256
+## end   gnulib module crypto/sha256-buffer
 
-## begin gnulib module crypto/sha512
-ifeq (,$(OMIT_GNULIB_MODULE_crypto/sha512))
+## begin gnulib module crypto/sha512-buffer
+ifeq (,$(OMIT_GNULIB_MODULE_crypto/sha512-buffer))
 
 libgnu_a_SOURCES += sha512.c
 
 EXTRA_DIST += gl_openssl.h sha512.h
 
 endif
-## end   gnulib module crypto/sha512
+## end   gnulib module crypto/sha512-buffer
 
 ## begin gnulib module diffseq
 ifeq (,$(OMIT_GNULIB_MODULE_diffseq))
@@ -1717,6 +1718,7 @@ inttypes.h: inttypes.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(WARN_ON_U
 	      -e 's/@''HAVE_DECL_IMAXDIV''@/$(HAVE_DECL_IMAXDIV)/g' \
 	      -e 's/@''HAVE_DECL_STRTOIMAX''@/$(HAVE_DECL_STRTOIMAX)/g' \
 	      -e 's/@''HAVE_DECL_STRTOUMAX''@/$(HAVE_DECL_STRTOUMAX)/g' \
+	      -e 's/@''HAVE_IMAXDIV_T''@/$(HAVE_IMAXDIV_T)/g' \
 	      -e 's/@''REPLACE_STRTOIMAX''@/$(REPLACE_STRTOIMAX)/g' \
 	      -e 's/@''REPLACE_STRTOUMAX''@/$(REPLACE_STRTOUMAX)/g' \
 	      -e 's/@''INT32_MAX_LT_INTMAX_MAX''@/$(INT32_MAX_LT_INTMAX_MAX)/g' \
@@ -2984,7 +2986,6 @@ unistd.h: unistd.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H
 	      -e 's|@''HAVE_SLEEP''@|$(HAVE_SLEEP)|g' \
 	      -e 's|@''HAVE_SYMLINK''@|$(HAVE_SYMLINK)|g' \
 	      -e 's|@''HAVE_SYMLINKAT''@|$(HAVE_SYMLINKAT)|g' \
-	      -e 's|@''HAVE_TRUNCATE''@|$(HAVE_TRUNCATE)|g' \
 	      -e 's|@''HAVE_UNLINKAT''@|$(HAVE_UNLINKAT)|g' \
 	      -e 's|@''HAVE_USLEEP''@|$(HAVE_USLEEP)|g' \
 	      -e 's|@''HAVE_DECL_ENVIRON''@|$(HAVE_DECL_ENVIRON)|g' \
@@ -2996,6 +2997,7 @@ unistd.h: unistd.in.h $(top_builddir)/config.status $(CXXDEFS_H) $(ARG_NONNULL_H
 	      -e 's|@''HAVE_DECL_GETPAGESIZE''@|$(HAVE_DECL_GETPAGESIZE)|g' \
 	      -e 's|@''HAVE_DECL_GETUSERSHELL''@|$(HAVE_DECL_GETUSERSHELL)|g' \
 	      -e 's|@''HAVE_DECL_SETHOSTNAME''@|$(HAVE_DECL_SETHOSTNAME)|g' \
+	      -e 's|@''HAVE_DECL_TRUNCATE''@|$(HAVE_DECL_TRUNCATE)|g' \
 	      -e 's|@''HAVE_DECL_TTYNAME_R''@|$(HAVE_DECL_TTYNAME_R)|g' \
 	      -e 's|@''HAVE_OS_H''@|$(HAVE_OS_H)|g' \
 	      -e 's|@''HAVE_SYS_PARAM_H''@|$(HAVE_SYS_PARAM_H)|g' \
diff --git a/lib/inttypes.in.h b/lib/inttypes.in.h
index ca3cec5b477..c7d7968e6e9 100644
--- a/lib/inttypes.in.h
+++ b/lib/inttypes.in.h
@@ -52,7 +52,7 @@
 /* Get CHAR_BIT.  */
 #include <limits.h>
 /* On mingw, __USE_MINGW_ANSI_STDIO only works if <stdio.h> is also included */
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
 # include <stdio.h>
 #endif
 
@@ -1067,11 +1067,13 @@ _GL_WARN_ON_USE (imaxabs, "imaxabs is unportable - "
 #endif
 
 #if @GNULIB_IMAXDIV@
-# if !@HAVE_DECL_IMAXDIV@
+# if !@HAVE_IMAXDIV_T@
 #  if !GNULIB_defined_imaxdiv_t
 typedef struct { intmax_t quot; intmax_t rem; } imaxdiv_t;
 #   define GNULIB_defined_imaxdiv_t 1
 #  endif
+# endif
+# if !@HAVE_DECL_IMAXDIV@
 extern imaxdiv_t imaxdiv (intmax_t, intmax_t);
 # endif
 #elif defined GNULIB_POSIXCHECK
diff --git a/lib/md5.c b/lib/md5.c
index 9dc915e2cf0..577aab46d7a 100644
--- a/lib/md5.c
+++ b/lib/md5.c
@@ -134,21 +134,29 @@ md5_finish_ctx (struct md5_ctx *ctx, void *resbuf)
 }
 #endif
 
+#if defined _LIBC || defined GL_COMPILE_CRYPTO_STREAM
+
+#include "af_alg.h"
+
 /* Compute MD5 message digest for bytes read from STREAM.  The
    resulting message digest number will be written into the 16 bytes
    beginning at RESBLOCK.  */
 int
 md5_stream (FILE *stream, void *resblock)
 {
-  struct md5_ctx ctx;
-  size_t sum;
+  switch (afalg_stream (stream, "md5", resblock, MD5_DIGEST_SIZE))
+    {
+    case 0: return 0;
+    case -EIO: return 1;
+    }
 
   char *buffer = malloc (BLOCKSIZE + 72);
   if (!buffer)
     return 1;
 
-  /* Initialize the computation context.  */
+  struct md5_ctx ctx;
   md5_init_ctx (&ctx);
+  size_t sum;
 
   /* Iterate over full file contents.  */
   while (1)
@@ -206,6 +214,7 @@ process_partial_block:
   free (buffer);
   return 0;
 }
+#endif
 
 #if ! HAVE_OPENSSL_MD5
 /* Compute MD5 message digest for LEN bytes beginning at BUFFER.  The
diff --git a/lib/md5.h b/lib/md5.h
index d89f819a97b..db031aac04c 100644
--- a/lib/md5.h
+++ b/lib/md5.h
@@ -122,8 +122,11 @@ extern void *__md5_buffer (const char *buffer, size_t len,
                            void *resblock) __THROW;
 
 # endif
-/* Compute MD5 message digest for bytes read from STREAM.  The
-   resulting message digest number will be written into the 16 bytes
+/* Compute MD5 message digest for bytes read from STREAM.
+   STREAM is an open file stream.  Regular files are handled more efficiently.
+   The contents of STREAM from its current position to its end will be read.
+   The case that the last operation on STREAM was an 'ungetc' is not supported.
+   The resulting message digest number will be written into the 16 bytes
    beginning at RESBLOCK.  */
 extern int __md5_stream (FILE *stream, void *resblock) __THROW;
 
diff --git a/lib/open.c b/lib/open.c
index b344f13a92a..792e258ba0b 100644
--- a/lib/open.c
+++ b/lib/open.c
@@ -86,7 +86,7 @@ open (const char *filename, int flags, ...)
   flags &= ~O_NONBLOCK;
 #endif
 
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
   if (strcmp (filename, "/dev/null") == 0)
     filename = "NUL";
 #endif
diff --git a/lib/pipe2.c b/lib/pipe2.c
index 807ba6a9f9d..c16d9351ec8 100644
--- a/lib/pipe2.c
+++ b/lib/pipe2.c
@@ -29,7 +29,7 @@
 # include "nonblocking.h"
 #endif
 
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
 /* Native Windows API.  */
 
 # include <io.h>
@@ -73,7 +73,7 @@ pipe2 (int fd[2], int flags)
       return -1;
     }
 
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
 /* Native Windows API.  */
 
   if (_pipe (fd, 4096, flags & ~O_NONBLOCK) < 0)
@@ -152,8 +152,7 @@ pipe2 (int fd[2], int flags)
 
 #endif
 
-#if GNULIB_defined_O_NONBLOCK || \
-  !((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__)
+#if GNULIB_defined_O_NONBLOCK || !(defined _WIN32 && ! defined __CYGWIN__)
  fail:
   {
     int saved_errno = errno;
diff --git a/lib/putenv.c b/lib/putenv.c
index 556d5f82302..801e372c329 100644
--- a/lib/putenv.c
+++ b/lib/putenv.c
@@ -34,7 +34,7 @@
 #include <string.h>
 #include <unistd.h>
 
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
 # define WIN32_LEAN_AND_MEAN
 # include <windows.h>
 #endif
@@ -153,7 +153,7 @@ putenv (char *string)
             *ep = string;
             break;
           }
-# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+# if defined _WIN32 && ! defined __CYGWIN__
       if (putenv_result == 0)
         {
           /* _putenv propagated "NAME= " into the subprocess environment;
diff --git a/lib/sha1.c b/lib/sha1.c
index ce0f0b2e71f..8306d887da5 100644
--- a/lib/sha1.c
+++ b/lib/sha1.c
@@ -122,21 +122,29 @@ sha1_finish_ctx (struct sha1_ctx *ctx, void *resbuf)
 }
 #endif
 
+#ifdef GL_COMPILE_CRYPTO_STREAM
+
+#include "af_alg.h"
+
 /* Compute SHA1 message digest for bytes read from STREAM.  The
-   resulting message digest number will be written into the 16 bytes
+   resulting message digest number will be written into the 20 bytes
    beginning at RESBLOCK.  */
 int
 sha1_stream (FILE *stream, void *resblock)
 {
-  struct sha1_ctx ctx;
-  size_t sum;
+  switch (afalg_stream (stream, "sha1", resblock, SHA1_DIGEST_SIZE))
+    {
+    case 0: return 0;
+    case -EIO: return 1;
+    }
 
   char *buffer = malloc (BLOCKSIZE + 72);
   if (!buffer)
     return 1;
 
-  /* Initialize the computation context.  */
+  struct sha1_ctx ctx;
   sha1_init_ctx (&ctx);
+  size_t sum;
 
   /* Iterate over full file contents.  */
   while (1)
@@ -194,6 +202,7 @@ sha1_stream (FILE *stream, void *resblock)
   free (buffer);
   return 0;
 }
+#endif
 
 #if ! HAVE_OPENSSL_SHA1
 /* Compute SHA1 message digest for LEN bytes beginning at BUFFER.  The
diff --git a/lib/sha1.h b/lib/sha1.h
index b1db15da1e7..9419750f485 100644
--- a/lib/sha1.h
+++ b/lib/sha1.h
@@ -87,8 +87,11 @@ extern void *sha1_read_ctx (const struct sha1_ctx *ctx, void *resbuf);
 extern void *sha1_buffer (const char *buffer, size_t len, void *resblock);
 
 # endif
-/* Compute SHA1 message digest for bytes read from STREAM.  The
-   resulting message digest number will be written into the 20 bytes
+/* Compute SHA1 message digest for bytes read from STREAM.
+   STREAM is an open file stream.  Regular files are handled more efficiently.
+   The contents of STREAM from its current position to its end will be read.
+   The case that the last operation on STREAM was an 'ungetc' is not supported.
+   The resulting message digest number will be written into the 20 bytes
    beginning at RESBLOCK.  */
 extern int sha1_stream (FILE *stream, void *resblock);
 
diff --git a/lib/sha256.c b/lib/sha256.c
index 85405b20fdf..a036befcafd 100644
--- a/lib/sha256.c
+++ b/lib/sha256.c
@@ -91,17 +91,17 @@ sha224_init_ctx (struct sha256_ctx *ctx)
   ctx->buflen = 0;
 }
 
-/* Copy the value from v into the memory location pointed to by *cp,
-   If your architecture allows unaligned access this is equivalent to
-   * (uint32_t *) cp = v  */
+/* Copy the value from v into the memory location pointed to by *CP,
+   If your architecture allows unaligned access, this is equivalent to
+   * (__typeof__ (v) *) cp = v  */
 static void
 set_uint32 (char *cp, uint32_t v)
 {
   memcpy (cp, &v, sizeof v);
 }
 
-/* Put result from CTX in first 32 bytes following RESBUF.  The result
-   must be in little endian byte order.  */
+/* Put result from CTX in first 32 bytes following RESBUF.
+   The result must be in little endian byte order.  */
 void *
 sha256_read_ctx (const struct sha256_ctx *ctx, void *resbuf)
 {
@@ -169,21 +169,32 @@ sha224_finish_ctx (struct sha256_ctx *ctx, void *resbuf)
 }
 #endif
 
-/* Compute SHA256 message digest for bytes read from STREAM.  The
-   resulting message digest number will be written into the 32 bytes
-   beginning at RESBLOCK.  */
-int
-sha256_stream (FILE *stream, void *resblock)
+#ifdef GL_COMPILE_CRYPTO_STREAM
+
+#include "af_alg.h"
+
+/* Compute message digest for bytes read from STREAM using algorithm ALG.
+   Write the message digest into RESBLOCK, which contains HASHLEN bytes.
+   The initial and finishing operations are INIT_CTX and FINISH_CTX.
+   Return zero if and only if successful.  */
+static int
+shaxxx_stream (FILE *stream, char const *alg, void *resblock,
+               ssize_t hashlen, void (*init_ctx) (struct sha256_ctx *),
+               void *(*finish_ctx) (struct sha256_ctx *, void *))
 {
-  struct sha256_ctx ctx;
-  size_t sum;
+  switch (afalg_stream (stream, alg, resblock, hashlen))
+    {
+    case 0: return 0;
+    case -EIO: return 1;
+    }
 
   char *buffer = malloc (BLOCKSIZE + 72);
   if (!buffer)
     return 1;
 
-  /* Initialize the computation context.  */
-  sha256_init_ctx (&ctx);
+  struct sha256_ctx ctx;
+  init_ctx (&ctx);
+  size_t sum;
 
   /* Iterate over full file contents.  */
   while (1)
@@ -237,84 +248,28 @@ sha256_stream (FILE *stream, void *resblock)
     sha256_process_bytes (buffer, sum, &ctx);
 
   /* Construct result in desired memory.  */
-  sha256_finish_ctx (&ctx, resblock);
+  finish_ctx (&ctx, resblock);
   free (buffer);
   return 0;
 }
 
-/* FIXME: Avoid code duplication */
 int
-sha224_stream (FILE *stream, void *resblock)
+sha256_stream (FILE *stream, void *resblock)
 {
-  struct sha256_ctx ctx;
-  size_t sum;
-
-  char *buffer = malloc (BLOCKSIZE + 72);
-  if (!buffer)
-    return 1;
-
-  /* Initialize the computation context.  */
-  sha224_init_ctx (&ctx);
-
-  /* Iterate over full file contents.  */
-  while (1)
-    {
-      /* We read the file in blocks of BLOCKSIZE bytes.  One call of the
-         computation function processes the whole buffer so that with the
-         next round of the loop another block can be read.  */
-      size_t n;
-      sum = 0;
-
-      /* Read block.  Take care for partial reads.  */
-      while (1)
-        {
-          n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream);
-
-          sum += n;
-
-          if (sum == BLOCKSIZE)
-            break;
-
-          if (n == 0)
-            {
-              /* Check for the error flag IFF N == 0, so that we don't
-                 exit the loop after a partial read due to e.g., EAGAIN
-                 or EWOULDBLOCK.  */
-              if (ferror (stream))
-                {
-                  free (buffer);
-                  return 1;
-                }
-              goto process_partial_block;
-            }
-
-          /* We've read at least one byte, so ignore errors.  But always
-             check for EOF, since feof may be true even though N > 0.
-             Otherwise, we could end up calling fread after EOF.  */
-          if (feof (stream))
-            goto process_partial_block;
-        }
-
-      /* Process buffer with BLOCKSIZE bytes.  Note that
-                        BLOCKSIZE % 64 == 0
-       */
-      sha256_process_block (buffer, BLOCKSIZE, &ctx);
-    }
-
- process_partial_block:;
-
-  /* Process any remaining bytes.  */
-  if (sum > 0)
-    sha256_process_bytes (buffer, sum, &ctx);
+  return shaxxx_stream (stream, "sha256", resblock, SHA256_DIGEST_SIZE,
+                        sha256_init_ctx, sha256_finish_ctx);
+}
 
-  /* Construct result in desired memory.  */
-  sha224_finish_ctx (&ctx, resblock);
-  free (buffer);
-  return 0;
+int
+sha224_stream (FILE *stream, void *resblock)
+{
+  return shaxxx_stream (stream, "sha224", resblock, SHA224_DIGEST_SIZE,
+                        sha224_init_ctx, sha224_finish_ctx);
 }
+#endif
 
 #if ! HAVE_OPENSSL_SHA256
-/* Compute SHA512 message digest for LEN bytes beginning at BUFFER.  The
+/* Compute SHA256 message digest for LEN bytes beginning at BUFFER.  The
    result is always in little endian byte order, so that a byte-wise
    output yields to the wanted ASCII representation of the message
    digest.  */
diff --git a/lib/sha256.h b/lib/sha256.h
index e3449864bb6..19ed3ccd4d0 100644
--- a/lib/sha256.h
+++ b/lib/sha256.h
@@ -89,8 +89,11 @@ extern void *sha256_buffer (const char *buffer, size_t len, void *resblock);
 extern void *sha224_buffer (const char *buffer, size_t len, void *resblock);
 
 # endif
-/* Compute SHA256 (SHA224) message digest for bytes read from STREAM.  The
-   resulting message digest number will be written into the 32 (28) bytes
+/* Compute SHA256 (SHA224) message digest for bytes read from STREAM.
+   STREAM is an open file stream.  Regular files are handled more efficiently.
+   The contents of STREAM from its current position to its end will be read.
+   The case that the last operation on STREAM was an 'ungetc' is not supported.
+   The resulting message digest number will be written into the 32 (28) bytes
    beginning at RESBLOCK.  */
 extern int sha256_stream (FILE *stream, void *resblock);
 extern int sha224_stream (FILE *stream, void *resblock);
diff --git a/lib/sha512.c b/lib/sha512.c
index 8a6dd4e83ac..e175e705f52 100644
--- a/lib/sha512.c
+++ b/lib/sha512.c
@@ -177,21 +177,32 @@ sha384_finish_ctx (struct sha512_ctx *ctx, void *resbuf)
 }
 #endif
 
-/* Compute SHA512 message digest for bytes read from STREAM.  The
-   resulting message digest number will be written into the 64 bytes
-   beginning at RESBLOCK.  */
-int
-sha512_stream (FILE *stream, void *resblock)
+#ifdef GL_COMPILE_CRYPTO_STREAM
+
+#include "af_alg.h"
+
+/* Compute message digest for bytes read from STREAM using algorithm ALG.
+   Write the message digest into RESBLOCK, which contains HASHLEN bytes.
+   The initial and finishing operations are INIT_CTX and FINISH_CTX.
+   Return zero if and only if successful.  */
+static int
+shaxxx_stream (FILE *stream, char const *alg, void *resblock,
+               ssize_t hashlen, void (*init_ctx) (struct sha512_ctx *),
+               void *(*finish_ctx) (struct sha512_ctx *, void *))
 {
-  struct sha512_ctx ctx;
-  size_t sum;
+  switch (afalg_stream (stream, alg, resblock, hashlen))
+    {
+    case 0: return 0;
+    case -EIO: return 1;
+    }
 
   char *buffer = malloc (BLOCKSIZE + 72);
   if (!buffer)
     return 1;
 
-  /* Initialize the computation context.  */
-  sha512_init_ctx (&ctx);
+  struct sha512_ctx ctx;
+  init_ctx (&ctx);
+  size_t sum;
 
   /* Iterate over full file contents.  */
   while (1)
@@ -245,81 +256,25 @@ sha512_stream (FILE *stream, void *resblock)
     sha512_process_bytes (buffer, sum, &ctx);
 
   /* Construct result in desired memory.  */
-  sha512_finish_ctx (&ctx, resblock);
+  finish_ctx (&ctx, resblock);
   free (buffer);
   return 0;
 }
 
-/* FIXME: Avoid code duplication */
 int
-sha384_stream (FILE *stream, void *resblock)
+sha512_stream (FILE *stream, void *resblock)
 {
-  struct sha512_ctx ctx;
-  size_t sum;
-
-  char *buffer = malloc (BLOCKSIZE + 72);
-  if (!buffer)
-    return 1;
-
-  /* Initialize the computation context.  */
-  sha384_init_ctx (&ctx);
-
-  /* Iterate over full file contents.  */
-  while (1)
-    {
-      /* We read the file in blocks of BLOCKSIZE bytes.  One call of the
-         computation function processes the whole buffer so that with the
-         next round of the loop another block can be read.  */
-      size_t n;
-      sum = 0;
-
-      /* Read block.  Take care for partial reads.  */
-      while (1)
-        {
-          n = fread (buffer + sum, 1, BLOCKSIZE - sum, stream);
-
-          sum += n;
-
-          if (sum == BLOCKSIZE)
-            break;
-
-          if (n == 0)
-            {
-              /* Check for the error flag IFF N == 0, so that we don't
-                 exit the loop after a partial read due to e.g., EAGAIN
-                 or EWOULDBLOCK.  */
-              if (ferror (stream))
-                {
-                  free (buffer);
-                  return 1;
-                }
-              goto process_partial_block;
-            }
-
-          /* We've read at least one byte, so ignore errors.  But always
-             check for EOF, since feof may be true even though N > 0.
-             Otherwise, we could end up calling fread after EOF.  */
-          if (feof (stream))
-            goto process_partial_block;
-        }
-
-      /* Process buffer with BLOCKSIZE bytes.  Note that
-                        BLOCKSIZE % 128 == 0
-       */
-      sha512_process_block (buffer, BLOCKSIZE, &ctx);
-    }
-
- process_partial_block:;
-
-  /* Process any remaining bytes.  */
-  if (sum > 0)
-    sha512_process_bytes (buffer, sum, &ctx);
+  return shaxxx_stream (stream, "sha512", resblock, SHA512_DIGEST_SIZE,
+                        sha512_init_ctx, sha512_finish_ctx);
+}
 
-  /* Construct result in desired memory.  */
-  sha384_finish_ctx (&ctx, resblock);
-  free (buffer);
-  return 0;
+int
+sha384_stream (FILE *stream, void *resblock)
+{
+  return shaxxx_stream (stream, "sha384", resblock, SHA384_DIGEST_SIZE,
+                        sha384_init_ctx, sha384_finish_ctx);
 }
+#endif
 
 #if ! HAVE_OPENSSL_SHA512
 /* Compute SHA512 message digest for LEN bytes beginning at BUFFER.  The
diff --git a/lib/sha512.h b/lib/sha512.h
index 6a0aadba02f..2c39ab195cf 100644
--- a/lib/sha512.h
+++ b/lib/sha512.h
@@ -92,8 +92,11 @@ extern void *sha512_buffer (const char *buffer, size_t len, void *resblock);
 extern void *sha384_buffer (const char *buffer, size_t len, void *resblock);
 
 # endif
-/* Compute SHA512 (SHA384) message digest for bytes read from STREAM.  The
-   resulting message digest number will be written into the 64 (48) bytes
+/* Compute SHA512 (SHA384) message digest for bytes read from STREAM.
+   STREAM is an open file stream.  Regular files are handled more efficiently.
+   The contents of STREAM from its current position to its end will be read.
+   The case that the last operation on STREAM was an 'ungetc' is not supported.
+   The resulting message digest number will be written into the 64 (48) bytes
    beginning at RESBLOCK.  */
 extern int sha512_stream (FILE *stream, void *resblock);
 extern int sha384_stream (FILE *stream, void *resblock);
diff --git a/lib/stat-time.h b/lib/stat-time.h
index 104f5376682..8e787bd3b2d 100644
--- a/lib/stat-time.h
+++ b/lib/stat-time.h
@@ -168,7 +168,7 @@ get_stat_birthtime (struct stat const *st _GL_UNUSED)
 #elif defined HAVE_STRUCT_STAT_ST_BIRTHTIMENSEC
   t.tv_sec = st->st_birthtime;
   t.tv_nsec = st->st_birthtimensec;
-#elif (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#elif defined _WIN32 && ! defined __CYGWIN__
   /* Native Windows platforms (but not Cygwin) put the "file creation
      time" in st_ctime (!).  See
      <https://msdn.microsoft.com/en-us/library/14h5k7ff(VS.80).aspx>.  */
diff --git a/lib/stdio-impl.h b/lib/stdio-impl.h
index 05c5752a243..393ef0cf58d 100644
--- a/lib/stdio-impl.h
+++ b/lib/stdio-impl.h
@@ -60,25 +60,79 @@
 #  define _flags pub._flags
 #  define _r pub._r
 #  define _w pub._w
+# elif defined __ANDROID__ /* Android */
+  /* Up to this commit from 2015-10-12
+     <https://android.googlesource.com/platform/bionic.git/+/f0141dfab10a4b332769d52fa76631a64741297a>
+     the innards of FILE were public, and fp_ub could be defined like for OpenBSD,
+     see <https://android.googlesource.com/platform/bionic.git/+/e78392637d5086384a5631ddfdfa8d7ec8326ee3/libc/stdio/fileext.h>
+     and <https://android.googlesource.com/platform/bionic.git/+/e78392637d5086384a5631ddfdfa8d7ec8326ee3/libc/stdio/local.h>.
+     After this commit, the innards of FILE are hidden.  */
+#  define fp_ ((struct { unsigned char *_p; \
+                         int _r; \
+                         int _w; \
+                         int _flags; \
+                         int _file; \
+                         struct { unsigned char *_base; size_t _size; } _bf; \
+                         int _lbfsize; \
+                         void *_cookie; \
+                         void *_close; \
+                         void *_read; \
+                         void *_seek; \
+                         void *_write; \
+                         struct { unsigned char *_base; size_t _size; } _ext; \
+                         unsigned char *_up; \
+                         int _ur; \
+                         unsigned char _ubuf[3]; \
+                         unsigned char _nbuf[1]; \
+                         struct { unsigned char *_base; size_t _size; } _lb; \
+                         int _blksize; \
+                         fpos_t _offset; \
+                         /* More fields, not relevant here.  */ \
+                       } *) fp)
 # else
 #  define fp_ fp
 # endif
 
-# if (defined __NetBSD__ && __NetBSD_Version__ >= 105270000) || defined __OpenBSD__ || defined __minix || defined __ANDROID__ /* NetBSD >= 1.5ZA, OpenBSD, Minix 3, Android */
+# if (defined __NetBSD__ && __NetBSD_Version__ >= 105270000) || defined __OpenBSD__ || defined __minix /* NetBSD >= 1.5ZA, OpenBSD, Minix 3 */
   /* See <http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup>
-     and <https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup> */
+     and <https://cvsweb.openbsd.org/cgi-bin/cvsweb/src/lib/libc/stdio/fileext.h?rev=HEAD&content-type=text/x-cvsweb-markup>
+     and <https://github.com/Stichting-MINIX-Research-Foundation/minix/blob/master/lib/libc/stdio/fileext.h> */
   struct __sfileext
     {
       struct  __sbuf _ub; /* ungetc buffer */
       /* More fields, not relevant here.  */
     };
 #  define fp_ub ((struct __sfileext *) fp->_ext._base)->_ub
-# else                                         /* FreeBSD, NetBSD <= 1.5Z, DragonFly, Mac OS X, Cygwin, Android */
+# elif defined __ANDROID__                     /* Android */
+  struct __sfileext
+    {
+      struct { unsigned char *_base; size_t _size; } _ub; /* ungetc buffer */
+      /* More fields, not relevant here.  */
+    };
+#  define fp_ub ((struct __sfileext *) fp_->_ext._base)->_ub
+# else                                         /* FreeBSD, NetBSD <= 1.5Z, DragonFly, Mac OS X, Cygwin */
 #  define fp_ub fp_->_ub
 # endif
 
 # define HASUB(fp) (fp_ub._base != NULL)
 
+# if defined __ANDROID__ /* Android */
+  /* Needed after this commit from 2016-01-25
+     <https://android.googlesource.com/platform/bionic.git/+/e70e0e9267d069bf56a5078c99307e08a7280de7> */
+#  ifndef __SEOF
+#   define __SLBF 1
+#   define __SNBF 2
+#   define __SRD 4
+#   define __SWR 8
+#   define __SRW 0x10
+#   define __SEOF 0x20
+#   define __SERR 0x40
+#  endif
+#  ifndef __SOFF
+#   define __SOFF 0x1000
+#  endif
+# endif
+
 #endif
 
 
@@ -118,7 +172,7 @@
 #  define _flag __flag
 # endif
 
-#elif (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__  /* newer Windows with MSVC */
+#elif defined _WIN32 && ! defined __CYGWIN__  /* newer Windows with MSVC */
 
 /* <stdio.h> does not define the innards of FILE any more.  */
 # define WINDOWS_OPAQUE_FILE
diff --git a/lib/stdio.in.h b/lib/stdio.in.h
index b9a43bb80ca..ff7c9c831ac 100644
--- a/lib/stdio.in.h
+++ b/lib/stdio.in.h
@@ -122,7 +122,7 @@
    it before we  #define perror rpl_perror.  */
 /* But in any case avoid namespace pollution on glibc systems.  */
 #if (@GNULIB_PERROR@ || defined GNULIB_POSIXCHECK) \
-    && ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__) \
+    && (defined _WIN32 && ! defined __CYGWIN__) \
     && ! defined __GLIBC__
 # include <stdlib.h>
 #endif
@@ -133,7 +133,7 @@
    it before we  #define rename rpl_rename.  */
 /* But in any case avoid namespace pollution on glibc systems.  */
 #if (@GNULIB_REMOVE@ || @GNULIB_RENAME@ || defined GNULIB_POSIXCHECK) \
-    && ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__) \
+    && (defined _WIN32 && ! defined __CYGWIN__) \
     && ! defined __GLIBC__
 # include <io.h>
 #endif
diff --git a/lib/stdlib.in.h b/lib/stdlib.in.h
index c8a5d0d0c61..3bf35bf6b0f 100644
--- a/lib/stdlib.in.h
+++ b/lib/stdlib.in.h
@@ -54,7 +54,7 @@
 #endif
 
 /* Native Windows platforms declare mktemp() in <io.h>.  */
-#if 0 && ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__)
+#if 0 && (defined _WIN32 && ! defined __CYGWIN__)
 # include <io.h>
 #endif
 
@@ -90,7 +90,7 @@ struct random_data
 # endif
 #endif
 
-#if (@GNULIB_MKSTEMP@ || @GNULIB_MKSTEMPS@ || @GNULIB_GETSUBOPT@ || defined GNULIB_POSIXCHECK) && ! defined __GLIBC__ && !((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__)
+#if (@GNULIB_MKSTEMP@ || @GNULIB_MKSTEMPS@ || @GNULIB_GETSUBOPT@ || defined GNULIB_POSIXCHECK) && ! defined __GLIBC__ && !(defined _WIN32 && ! defined __CYGWIN__)
 /* On Mac OS X 10.3, only <unistd.h> declares mkstemp.  */
 /* On Mac OS X 10.5, only <unistd.h> declares mkstemps.  */
 /* On Cygwin 1.7.1, only <unistd.h> declares getsubopt.  */
diff --git a/lib/sys_stat.in.h b/lib/sys_stat.in.h
index d96fde1007d..6ae6ac5fbdc 100644
--- a/lib/sys_stat.in.h
+++ b/lib/sys_stat.in.h
@@ -57,13 +57,13 @@
 /* Before doing "#define mkdir rpl_mkdir" below, we need to include all
    headers that may declare mkdir().  Native Windows platforms declare mkdir
    in <io.h> and/or <direct.h>, not in <unistd.h>.  */
-#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+#if defined _WIN32 && ! defined __CYGWIN__
 # include <io.h>     /* mingw32, mingw64 */
 # include <direct.h> /* mingw64, MSVC 9 */
 #endif
 
 /* Native Windows platforms declare umask() in <io.h>.  */
-#if 0 && ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__)
+#if 0 && (defined _WIN32 && ! defined __CYGWIN__)
 # include <io.h>
 #endif
 
@@ -576,7 +576,7 @@ _GL_CXXALIAS_RPL (mkdir, int, (char const *name, mode_t mode));
    Additionally, it declares _mkdir (and depending on compile flags, an
    alias mkdir), only in the nonstandard includes <direct.h> and <io.h>,
    which are included above.  */
-# if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+# if defined _WIN32 && ! defined __CYGWIN__
 
 #  if !GNULIB_defined_rpl_mkdir
 static int
diff --git a/lib/sys_types.in.h b/lib/sys_types.in.h
index 747371644df..7f8c1c42117 100644
--- a/lib/sys_types.in.h
+++ b/lib/sys_types.in.h
@@ -20,6 +20,17 @@
 #endif
 @PRAGMA_COLUMNS@
 
+#if defined _WIN32 && !defined __CYGWIN__ \
+    && (defined __need_off_t || defined __need___off64_t \
+        || defined __need_ssize_t || defined __need_time_t)
+
+/* Special invocation convention inside mingw header files.  */
+
+#@INCLUDE_NEXT@ @NEXT_SYS_TYPES_H@
+
+#else
+/* Normal invocation convention.  */
+
 #ifndef _@GUARD_PREFIX@_SYS_TYPES_H
 
 /* The include_next requires a split double-inclusion guard.  */
@@ -86,10 +97,10 @@ typedef unsigned long long int rpl_ino_t;
 
 /* MSVC 9 defines size_t in <stddef.h>, not in <sys/types.h>.  */
 /* But avoid namespace pollution on glibc systems.  */
-#if ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__) \
-    && ! defined __GLIBC__
+#if (defined _WIN32 && ! defined __CYGWIN__) && ! defined __GLIBC__
 # include <stddef.h>
 #endif
 
 #endif /* _@GUARD_PREFIX@_SYS_TYPES_H */
 #endif /* _@GUARD_PREFIX@_SYS_TYPES_H */
+#endif /* __need_XXX */
diff --git a/lib/timespec.h b/lib/timespec.h
index eef3030d9c5..94ba8d0b6a0 100644
--- a/lib/timespec.h
+++ b/lib/timespec.h
@@ -87,7 +87,7 @@ timespec_cmp (struct timespec a, struct timespec b)
     return 1;
 
   /* Pacify gcc -Wstrict-overflow (bleeding-edge circa 2017-10-02).  See:
-     http://lists.gnu.org/r/bug-gnulib/2017-10/msg00006.html  */
+     https://lists.gnu.org/r/bug-gnulib/2017-10/msg00006.html  */
   assume (-1 <= a.tv_nsec && a.tv_nsec <= 2 * TIMESPEC_RESOLUTION);
   assume (-1 <= b.tv_nsec && b.tv_nsec <= 2 * TIMESPEC_RESOLUTION);
 
diff --git a/lib/unistd.in.h b/lib/unistd.in.h
index beeb8e1d6fd..b6a348f5297 100644
--- a/lib/unistd.in.h
+++ b/lib/unistd.in.h
@@ -61,7 +61,7 @@
 /* But avoid namespace pollution on glibc systems.  */
 #if (!(defined SEEK_CUR && defined SEEK_END && defined SEEK_SET) \
      || ((@GNULIB_UNLINK@ || defined GNULIB_POSIXCHECK) \
-         && ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__)) \
+         && (defined _WIN32 && ! defined __CYGWIN__)) \
      || ((@GNULIB_SYMLINKAT@ || defined GNULIB_POSIXCHECK) \
          && defined __CYGWIN__)) \
     && ! defined __GLIBC__
@@ -94,13 +94,13 @@
    lseek(), read(), unlink(), write() in <io.h>.  */
 #if ((@GNULIB_CHDIR@ || @GNULIB_GETCWD@ || @GNULIB_RMDIR@ \
       || defined GNULIB_POSIXCHECK) \
-     && ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__))
+     && (defined _WIN32 && ! defined __CYGWIN__))
 # include <io.h>     /* mingw32, mingw64 */
 # include <direct.h> /* mingw64, MSVC 9 */
 #elif (@GNULIB_CLOSE@ || @GNULIB_DUP@ || @GNULIB_DUP2@ || @GNULIB_ISATTY@ \
        || @GNULIB_LSEEK@ || @GNULIB_READ@ || @GNULIB_UNLINK@ || @GNULIB_WRITE@ \
        || defined GNULIB_POSIXCHECK) \
-      && ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__)
+      && (defined _WIN32 && ! defined __CYGWIN__)
 # include <io.h>
 #endif
 
@@ -1489,7 +1489,7 @@ _GL_FUNCDECL_RPL (truncate, int, (const char *filename, off_t length)
                                  _GL_ARG_NONNULL ((1)));
 _GL_CXXALIAS_RPL (truncate, int, (const char *filename, off_t length));
 # else
-#  if !@HAVE_TRUNCATE@
+#  if !@HAVE_DECL_TRUNCATE@
 _GL_FUNCDECL_SYS (truncate, int, (const char *filename, off_t length)
                                  _GL_ARG_NONNULL ((1)));
 #  endif
diff --git a/lib/utimens.c b/lib/utimens.c
index c0b0704eb29..e65f55d82fe 100644
--- a/lib/utimens.c
+++ b/lib/utimens.c
@@ -39,8 +39,7 @@
    GNU Emacs, which arranges for this in some other way and which
    defines WIN32_LEAN_AND_MEAN itself.  */
 
-#if ((defined _WIN32 || defined __WIN32__) \
-     && ! defined __CYGWIN__ && ! defined EMACS_CONFIGURATION)
+#if defined _WIN32 && ! defined __CYGWIN__ && ! defined EMACS_CONFIGURATION
 # define USE_SETFILETIME
 # define WIN32_LEAN_AND_MEAN
 # include <windows.h>