gnu: findutils: Fix build with glibc 2.28.

* gnu/packages/patches/findutils-gnulib-libio.patch,
gnu/packages/patches/findutils-makedev.patch: New files.
* gnu/local.mk (dist_patch_DATA): Register it.
* gnu/packages/base.scm (findutils)[source](patches): Use them.

gnu/local.mk

@@ -671,7 +671,9 @@ dist_patch_DATA =						\
   %D%/packages/patches/fcgi-2.4.0-poll.patch			\
   %D%/packages/patches/fifo-map-fix-flags-for-gcc.patch		\
   %D%/packages/patches/fifo-map-remove-catch.hpp.patch		\
+  %D%/packages/patches/findutils-gnulib-libio.patch		\
   %D%/packages/patches/findutils-localstatedir.patch		\
+  %D%/packages/patches/findutils-makedev.patch			\
   %D%/packages/patches/findutils-test-xargs.patch		\
   %D%/packages/patches/flann-cmake-3.11.patch			\
   %D%/packages/patches/flint-ldconfig.patch			\

gnu/packages/base.scm

@@ -298,7 +298,9 @@ interactive means to merge two files.")
              (base32
               "178nn4dl7wbcw499czikirnkniwnx36argdnqgz4ik9i6zvwkm6y"))
             (patches (search-patches
+                      "findutils-gnulib-libio.patch"
                       "findutils-localstatedir.patch"
+                      "findutils-makedev.patch"
                       "findutils-test-xargs.patch"))
             (modules '((guix build utils)))
             (snippet

gnu/packages/patches/findutils-gnulib-libio.patch

@@ -0,0 +1,114 @@
+Adjust to removal of libio interface in glibc 2.28.
+
+Based on this gnulib commit:
+https://git.savannah.gnu.org/cgit/gnulib.git/commit/?id=4af4a4a71827c0bc5e0ec67af23edef4f15cee8e
+
+diff --git a/gl/lib/fflush.c b/gl/lib/fflush.c
+index 5ae3e41..7a82470 100644
+--- a/gl/lib/fflush.c
++++ b/gl/lib/fflush.c
+@@ -33,7 +33,7 @@
+ #undef fflush
+ 
+ 
+-#if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
++#if defined _IO_EOF_SEEN || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+ 
+ /* Clear the stream's ungetc buffer, preserving the value of ftello (fp).  */
+ static void
+@@ -72,7 +72,7 @@ clear_ungetc_buffer (FILE *fp)
+ 
+ #endif
+ 
+-#if ! (defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */)
++#if ! (defined _IO_EOF_SEEN || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */)
+ 
+ # if (defined __sferror || defined __DragonFly__ || defined __ANDROID__) && defined __SNPT
+ /* FreeBSD, NetBSD, OpenBSD, DragonFly, Mac OS X, Cygwin, Android */
+@@ -148,7 +148,7 @@ rpl_fflush (FILE *stream)
+   if (stream == NULL || ! freading (stream))
+     return fflush (stream);
+ 
+-#if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
++#if defined _IO_EOF_SEEN || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+ 
+   clear_ungetc_buffer_preserving_position (stream);
+ 
+diff --git a/gl/lib/fpurge.c b/gl/lib/fpurge.c
+index f313b22..ecdf82d 100644
+--- a/gl/lib/fpurge.c
++++ b/gl/lib/fpurge.c
+@@ -62,7 +62,7 @@ fpurge (FILE *fp)
+   /* Most systems provide FILE as a struct and the necessary bitmask in
+      <stdio.h>, because they need it for implementing getc() and putc() as
+      fast macros.  */
+-# if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
++# if defined _IO_EOF_SEEN || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+   fp->_IO_read_end = fp->_IO_read_ptr;
+   fp->_IO_write_ptr = fp->_IO_write_base;
+   /* Avoid memory leak when there is an active ungetc buffer.  */
+diff --git a/gl/lib/freadahead.c b/gl/lib/freadahead.c
+index 094daab..3f8101e 100644
+--- a/gl/lib/freadahead.c
++++ b/gl/lib/freadahead.c
+@@ -25,7 +25,7 @@
+ size_t
+ freadahead (FILE *fp)
+ {
+-#if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
++#if defined _IO_EOF_SEEN || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+   if (fp->_IO_write_ptr > fp->_IO_write_base)
+     return 0;
+   return (fp->_IO_read_end - fp->_IO_read_ptr)
+diff --git a/gl/lib/freading.c b/gl/lib/freading.c
+index 0512b19..8c48fe4 100644
+--- a/gl/lib/freading.c
++++ b/gl/lib/freading.c
+@@ -31,7 +31,7 @@ freading (FILE *fp)
+   /* Most systems provide FILE as a struct and the necessary bitmask in
+      <stdio.h>, because they need it for implementing getc() and putc() as
+      fast macros.  */
+-# if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
++# if defined _IO_EOF_SEEN || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+   return ((fp->_flags & _IO_NO_WRITES) != 0
+           || ((fp->_flags & (_IO_NO_READS | _IO_CURRENTLY_PUTTING)) == 0
+               && fp->_IO_read_base != NULL));
+diff --git a/gl/lib/fseeko.c b/gl/lib/fseeko.c
+index 1c65d2a..9026408 100644
+--- a/gl/lib/fseeko.c
++++ b/gl/lib/fseeko.c
+@@ -47,7 +47,7 @@ fseeko (FILE *fp, off_t offset, int whence)
+ #endif
+ 
+   /* These tests are based on fpurge.c.  */
+-#if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
++#if defined _IO_EOF_SEEN || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+   if (fp->_IO_read_end == fp->_IO_read_ptr
+       && fp->_IO_write_ptr == fp->_IO_write_base
+       && fp->_IO_save_base == NULL)
+@@ -123,7 +123,7 @@ fseeko (FILE *fp, off_t offset, int whence)
+           return -1;
+         }
+ 
+-#if defined _IO_ftrylockfile || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
++#if defined _IO_EOF_SEEN || __GNU_LIBRARY__ == 1 /* GNU libc, BeOS, Haiku, Linux libc5 */
+       fp->_flags &= ~_IO_EOF_SEEN;
+       fp->_offset = pos;
+ #elif defined __sferror || defined __DragonFly__ || defined __ANDROID__
+diff --git a/gl/lib/stdio-impl.h b/gl/lib/stdio-impl.h
+index 502d891..ea38ee2 100644
+--- a/gl/lib/stdio-impl.h
++++ b/gl/lib/stdio-impl.h
+@@ -18,6 +18,12 @@
+    the same implementation of stdio extension API, except that some fields
+    have different naming conventions, or their access requires some casts.  */
+ 
++/* Glibc 2.28 made _IO_IN_BACKUP private.  For now, work around this
++   problem by defining it ourselves.  FIXME: Do not rely on glibc
++   internals.  */
++#if !defined _IO_IN_BACKUP && defined _IO_EOF_SEEN
++# define _IO_IN_BACKUP 0x100
++#endif
+ 
+ /* BSD stdio derived implementations.  */
+ 

gnu/packages/patches/findutils-makedev.patch

@@ -0,0 +1,22 @@
+Include <sys/sysmacros.h> for "makedev".
+
+Taken from this gnulib commit:
+https://git.savannah.gnu.org/cgit/gnulib.git/commit/?id=4da63c5881f60f71999a943612da9112232b9161
+
+diff --git a/gl/lib/mountlist.c b/gl/lib/mountlist.c
+index bb4e4ee21..cf4020e2a 100644
+--- a/gl/lib/mountlist.c
++++ b/gl/lib/mountlist.c
+@@ -37,6 +37,12 @@
+ # include <sys/param.h>
+ #endif
+ 
++#if MAJOR_IN_MKDEV
++# include <sys/mkdev.h>
++#elif MAJOR_IN_SYSMACROS
++# include <sys/sysmacros.h>
++#endif
++
+ #if defined MOUNTED_GETFSSTAT   /* OSF_1 and Darwin1.3.x */
+ # if HAVE_SYS_UCRED_H
+ #  include <grp.h> /* needed on OSF V4.0 for definition of NGROUPS,