gnu: qt@5: Fix build failure on glibc 2.28.

* gnu/packages/patches/qt-5-renameat2.patch: New file.
* gnu/packages/qt.scm (qt)[source]: Use it.
* gnu/local.mk (dist_patch_DATA): Add it.

gnu/local.mk

@@ -1099,6 +1099,7 @@ dist_patch_DATA =						\
   %D%/packages/patches/qt4-ldflags.patch			\
   %D%/packages/patches/qtbase-use-TZDIR.patch			\
   %D%/packages/patches/qtscript-disable-tests.patch		\
+  %D%/packages/patches/qt-5-renameat2.patch			\
   %D%/packages/patches/quagga-reproducible-build.patch          \
   %D%/packages/patches/quickswitch-fix-dmenu-check.patch	\
   %D%/packages/patches/quilt-test-fix-regex.patch		\

gnu/packages/patches/qt-5-renameat2.patch

@@ -0,0 +1,35 @@
+Avoid conflicting declaration of 'renameat2' on glibc 2.28
+(see <https://github.com/meta-qt5/meta-qt5/issues/94>.)
+
+Patch from <https://github.com/meta-qt5/meta-qt5/pull/95>
+by Andreas Müller <schnitzeltony@gmail.com>.
+
+---
+ src/corelib/io/qfilesystemengine_unix.cpp | 11 ++++++++++++
+ 1 file changed, 11 insertions(+)
+
+diff --git a/src/corelib/io/qfilesystemengine_unix.cpp b/src/corelib/io/qfilesystemengine_unix.cpp
+index be6ce48d0cb..1bf1bebc7f1 100644
+--- a/qtbase/src/corelib/io/qfilesystemengine_unix.cpp
++++ b/qtbase/src/corelib/io/qfilesystemengine_unix.cpp
+@@ -98,6 +98,17 @@ extern "C" NSString *NSTemporaryDirectory();
+ #  define FICLONE       _IOW(0x94, 9, int)
+ #endif
+ 
++// renameat2/statx features for non bootstrapped build
++#ifndef QT_BOOTSTRAPPED
++#ifdef __GLIBC_PREREQ
++# define QT_FEATURE_renameat2 (__GLIBC_PREREQ(2, 28) ? 1 : -1)
++# define QT_FEATURE_statx (__GLIBC_PREREQ(2, 28) ? 1 : -1)
++#else
++# define QT_FEATURE_renameat2 -1
++# define QT_FEATURE_statx -1
++#endif
++#endif
++
+ #  if defined(Q_OS_ANDROID)
+ // renameat2() and statx() are disabled on Android because quite a few systems
+ // come with sandboxes that kill applications that make system calls outside a
+-- 
+2.14.4
+

gnu/packages/qt.scm

@@ -1,7 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2013, 2014, 2015 Andreas Enge <andreas@enge.fr>
 ;;; Copyright © 2015 Sou Bunnbu <iyzsong@gmail.com>
-;;; Copyright © 2015 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2015, 2018 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2015, 2016, 2017, 2018 Efraim Flashner <efraim@flashner.co.il>
 ;;; Copyright © 2016, 2017 Nils Gillmann <ng0@n0.is>
 ;;; Copyright © 2016 Thomas Danckaert <post@thomasdanckaert.be>
@@ -121,6 +121,7 @@ system, and the core design of Django is reused in Grantlee.")
              (sha256
               (base32
                "10faac59jvz6dxxljdkaknlxazpnaxgvqdcszabfbbkc1f24n466"))
+             (patches (search-patches "qt-5-renameat2.patch"))
              (modules '((guix build utils)))
              (snippet
               '(begin