backport fix for build failure

0001-Adapt-o3tl-span-to-removal-of-std-span-cbegin-et-al.patch

@@ -0,0 +1,68 @@
+From 6fbfad6b00e8c35346ee59cd32a0d7ccc0d8c19c Mon Sep 17 00:00:00 2001
+From: Stephan Bergmann <sbergman@redhat.com>
+Date: Sat, 22 Feb 2020 17:29:15 +0100
+Subject: [PATCH] Adapt o3tl::span to removal of std::span::cbegin et al
+
+<https://cplusplus.github.io/LWG/issue3320> "span::cbegin/cend methods produce
+different results than std::[ranges::]cbegin/cend", as implemented now in
+<https://gcc.gnu.org/git/gitweb.cgi?p=gcc.git;a=commit;
+h=247f410b83797a1840573840cc2a539ef9d7f96b> "libstdc++: Remove std::span::cbegin
+and std::span::cend (LWG 3320)".
+
+Turns out we only used the removed member functions in o3tl/qa/test-span.cxx.
+
+Change-Id: I6c73797594b4e0e753a88840033d54961e271df5
+Reviewed-on: https://gerrit.libreoffice.org/c/core/+/89261
+Tested-by: Jenkins
+Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
+---
+ include/o3tl/span.hxx | 7 -------
+ o3tl/qa/test-span.cxx | 6 ------
+ 2 files changed, 13 deletions(-)
+
+diff --git a/include/o3tl/span.hxx b/include/o3tl/span.hxx
+index b19d2d847ac7..8af8ba846b65 100644
+--- a/include/o3tl/span.hxx
++++ b/include/o3tl/span.hxx
+@@ -62,18 +62,11 @@ public:
+     constexpr iterator begin() const noexcept { return data_; }
+     constexpr iterator end() const noexcept { return begin() + size(); }
+ 
+-    constexpr const_iterator cbegin() const noexcept { return begin(); }
+-    constexpr const_iterator cend() const noexcept { return end(); }
+-
+     reverse_iterator rbegin() const noexcept
+     { return reverse_iterator(end()); }
+     reverse_iterator rend() const noexcept
+     { return reverse_iterator(begin()); }
+ 
+-    constexpr const_reverse_iterator crbegin() const noexcept
+-    { return rbegin(); }
+-    constexpr const_reverse_iterator crend() const noexcept { return rend(); }
+-
+     constexpr size_type size() const noexcept { return size_; }
+ 
+     constexpr reference operator [](size_type pos) const {
+diff --git a/o3tl/qa/test-span.cxx b/o3tl/qa/test-span.cxx
+index 3cb78ace1db2..26eedfc21938 100644
+--- a/o3tl/qa/test-span.cxx
++++ b/o3tl/qa/test-span.cxx
+@@ -34,15 +34,9 @@ private:
+         CPPUNIT_ASSERT_EQUAL(1, *v.begin());
+         CPPUNIT_ASSERT_EQUAL(
+             o3tl::span<int>::difference_type(3), v.end() - v.begin());
+-        CPPUNIT_ASSERT_EQUAL(1, *v.cbegin());
+-        CPPUNIT_ASSERT_EQUAL(
+-            o3tl::span<int>::difference_type(3), v.cend() - v.cbegin());
+         CPPUNIT_ASSERT_EQUAL(3, *v.rbegin());
+         CPPUNIT_ASSERT_EQUAL(
+             o3tl::span<int>::difference_type(3), v.rend() - v.rbegin());
+-        CPPUNIT_ASSERT_EQUAL(3, *v.crbegin());
+-        CPPUNIT_ASSERT_EQUAL(
+-            o3tl::span<int>::difference_type(3), v.crend() - v.crbegin());
+         CPPUNIT_ASSERT_EQUAL(std::size_t(3), v.size());
+         CPPUNIT_ASSERT(!v.empty());
+         CPPUNIT_ASSERT_EQUAL(2, v[1]);
+-- 
+2.24.1
+

libreoffice.spec

@@ -243,6 +243,7 @@ Patch1: 0001-Resolves-rhbz-1432468-disable-opencl-by-default.patch
 # backported
 Patch2: 0001-replace-boost-bimap-in-sdext-pdfimport.patch
 Patch3: 0001-fix-detecting-qrcodegen.patch
+Patch4: 0001-Adapt-o3tl-span-to-removal-of-std-span-cbegin-et-al.patch
 
 %if 0%{?rhel}
 # not upstreamed