Update from Gnulib

This incorporates:
2020-08-12 stdint: port intptr_t to more-recent MinGW
2020-08-11 Use __restrict also on clang
2020-08-11 Use flexible array syntax also on clang
2020-08-11 fcntl: On native Windows, use _setmode, not setmode
* lib/binary-io.h, lib/cdefs.h, lib/fcntl.c, lib/regex.h:
* lib/stdint.in.h: Copy from Gnulib.

5 files changed, 26 insertions, 17 deletions

diff --git a/lib/binary-io.h b/lib/binary-io.h
index 477b4bf4dd3..d17af7c3807 100644
--- a/lib/binary-io.h
+++ b/lib/binary-io.h
@@ -56,7 +56,7 @@ __gl_setmode (int fd _GL_UNUSED, int mode _GL_UNUSED)
 /* Set FD's mode to MODE, which should be either O_TEXT or O_BINARY.
    Return the old mode if successful, -1 (setting errno) on failure.
    Ordinarily this function would be called 'setmode', since that is
-   its name on MS-Windows, but it is called 'set_binary_mode' here
+   its old name on MS-Windows, but it is called 'set_binary_mode' here
    to avoid colliding with a BSD function of another name.  */
 
 #if defined __DJGPP__ || defined __EMX__
diff --git a/lib/cdefs.h b/lib/cdefs.h
index beedd891fb8..4f89f4e4bf0 100644
--- a/lib/cdefs.h
+++ b/lib/cdefs.h
@@ -167,8 +167,8 @@
 #if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L && !defined __HP_cc
 # define __flexarr      []
 # define __glibc_c99_flexarr_available 1
-#elif __GNUC_PREREQ (2,97)
-/* GCC 2.97 supports C99 flexible array members as an extension,
+#elif __GNUC_PREREQ (2,97) || defined __clang__
+/* GCC 2.97 and clang support C99 flexible array members as an extension,
    even when in C89 mode or compiling C++ (any version).  */
 # define __flexarr      []
 # define __glibc_c99_flexarr_available 1
@@ -399,8 +399,10 @@
 # define __extension__          /* Ignore */
 #endif
 
-/* __restrict is known in EGCS 1.2 and above. */
-#if !__GNUC_PREREQ (2,92)
+/* __restrict is known in EGCS 1.2 and above, and in clang.
+   It works also in C++ mode (outside of arrays), but only when spelled
+   as '__restrict', not 'restrict'.  */
+#if !(__GNUC_PREREQ (2,92) || __clang_major__ >= 3)
 # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
 #  define __restrict    restrict
 # else
@@ -410,8 +412,9 @@
 
 /* ISO C99 also allows to declare arrays as non-overlapping.  The syntax is
      array_name[restrict]
-   GCC 3.1 supports this.  */
-#if __GNUC_PREREQ (3,1) && !defined __GNUG__
+   GCC 3.1 and clang support this.
+   This syntax is not usable in C++ mode.  */
+#if (__GNUC_PREREQ (3,1) || __clang_major__ >= 3) && !defined __cplusplus
 # define __restrict_arr __restrict
 #else
 # ifdef __GNUC__
diff --git a/lib/fcntl.c b/lib/fcntl.c
index 6b9927ec4e5..8cd1531527d 100644
--- a/lib/fcntl.c
+++ b/lib/fcntl.c
@@ -70,14 +70,14 @@ dupfd (int oldfd, int newfd, int flags)
       return -1;
     }
   if (old_handle == INVALID_HANDLE_VALUE
-      || (mode = setmode (oldfd, O_BINARY)) == -1)
+      || (mode = _setmode (oldfd, O_BINARY)) == -1)
     {
       /* oldfd is not open, or is an unassigned standard file
          descriptor.  */
       errno = EBADF;
       return -1;
     }
-  setmode (oldfd, mode);
+  _setmode (oldfd, mode);
   flags |= mode;
 
   for (;;)
diff --git a/lib/regex.h b/lib/regex.h
index 610f139eb39..306521a3e8a 100644
--- a/lib/regex.h
+++ b/lib/regex.h
@@ -612,7 +612,9 @@ extern int re_exec (const char *);
    'configure' might #define 'restrict' to those words, so pick a
    different name.  */
 #ifndef _Restrict_
-# if defined __restrict || 2 < __GNUC__ + (95 <= __GNUC_MINOR__)
+# if defined __restrict \
+     || 2 < __GNUC__ + (95 <= __GNUC_MINOR__) \
+     || __clang_major__ >= 3
 #  define _Restrict_ __restrict
 # elif 199901L <= __STDC_VERSION__ || defined restrict
 #  define _Restrict_ restrict
@@ -620,13 +622,18 @@ extern int re_exec (const char *);
 #  define _Restrict_
 # endif
 #endif
-/* For [restrict], use glibc's __restrict_arr if available.
-   Otherwise, GCC 3.1 (not in C++ mode) and C99 support [restrict].  */
+/* For the ISO C99 syntax
+     array_name[restrict]
+   use glibc's __restrict_arr if available.
+   Otherwise, GCC 3.1 and clang support this syntax (but not in C++ mode).
+   Other ISO C99 compilers support it as well.  */
 #ifndef _Restrict_arr_
 # ifdef __restrict_arr
 #  define _Restrict_arr_ __restrict_arr
-# elif ((199901L <= __STDC_VERSION__ || 3 < __GNUC__ + (1 <= __GNUC_MINOR__)) \
-        && !defined __GNUG__)
+# elif ((199901L <= __STDC_VERSION__ \
+         || 3 < __GNUC__ + (1 <= __GNUC_MINOR__) \
+         || __clang_major__ >= 3) \
+        && !defined __cplusplus)
 #  define _Restrict_arr_ _Restrict_
 # else
 #  define _Restrict_arr_
diff --git a/lib/stdint.in.h b/lib/stdint.in.h
index 994c0c777c0..63fa1aa628f 100644
--- a/lib/stdint.in.h
+++ b/lib/stdint.in.h
@@ -302,12 +302,11 @@ typedef gl_uint_fast32_t gl_uint_fast16_t;
 /* kLIBC's <stdint.h> defines _INTPTR_T_DECLARED and needs its own
    definitions of intptr_t and uintptr_t (which use int and unsigned)
    to avoid clashes with declarations of system functions like sbrk.
-   Similarly, mingw 5.22 <crtdefs.h> defines _INTPTR_T_DEFINED and
-   _UINTPTR_T_DEFINED and needs its own definitions of intptr_t and
+   Similarly, MinGW WSL-5.4.1 <stdint.h> needs its own intptr_t and
    uintptr_t to avoid conflicting declarations of system functions like
    _findclose in <io.h>.  */
 # if !((defined __KLIBC__ && defined _INTPTR_T_DECLARED) \
-       || (defined __MINGW32__ && defined _INTPTR_T_DEFINED && defined _UINTPTR_T_DEFINED))
+       || defined __MINGW32__)
 #  undef intptr_t
 #  undef uintptr_t
 #  ifdef _WIN64