From c2339a0d1bc5944c7b408371536848ac14c4b41a Mon Sep 17 00:00:00 2001
From: Herman Lee <herman@meta.com>
Date: Tue, 25 Apr 2023 09:11:32 -0700
Subject: [PATCH] [mysql-5.6][PR] Bug #34638573 Compile MySQL with clang 15

Summary:
Fixing two compile errors, that are triggered when using libcxx from LLVM15

https://reviews.llvm.org/D104002

std::unary_function is not available in libcxx under C++17, see: https://en.cppreference.com/w/cpp/utility/functional/unary_function Boost uses std::unary_function, but it has a workaround for using Boost headers in C++17, triggered by the macro BOOST_NO_CXX98_FUNCTION_BASE

See:
https://www.boost.org/doc/libs/master/libs/config/doc/html/boost_config/boost_macro_reference.html#boost_config.boost_macro_reference.macros_that_describe_features_that_have_been_removed_from_the_standard_

https://reviews.llvm.org/D130538

A new assert in libcxx is triggered in include/varlen_sort.h

std::iterator_traits<varlen_iterator>::reference should match the return type of varlen_iterator::operator*()

include/c++/v1/__algorithm/iterator_operations.h:100:5: error: static assertion failed due to requirement 'is_same<varlen_element, varlen_element &>::value': It looks like your iterator's `iterator_traits<It>::reference` does not match the return type of dereferencing the iterator, i.e., calling `*it`. This is undefined behavior according to [input.iterators] and can lead to dangling reference issues at runtime, so we are flagging this. static_assert(is_same<__deref_t<_Iter>, typename iterator_traits<__remove_cvref_t<_Iter> >::reference>::value,
^             ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fix a few warnings:
Remove some explicitly defined "=defau.t" constructors, destructors. warning: definition of implicit copy assignment operator for 'Row' is deprecated because it has a user-declared destructor [-Wdeprecated-copy-with-dtor]

Mark a variable potentially unuses in tests (unuses when __aarch64__)

Porting Notes: Drop when rebasing to 8.0.32

Change-Id: Iad346bd0cdb1d25d958377b9c7a0dd5da7a45fad

Pull Request resolved: https://github.com/facebook/mysql-5.6/pull/1293
GitHub Author: Gabor Buella <gabor.buella@oracle.com>

Test Plan: Imported from GitHub, without a `Test Plan:` line.

Reviewers: chni

Reviewed By: chni

Subscribers: webscalesql-eng@fb.com

Differential Revision: https://phabricator.intern.facebook.com/D45277622

Tags: aarch64, accept2ship
---
 cmake/boost.cmake                   |  3 +++
 include/varlen_sort.h               |  5 +++--
 storage/innobase/include/ddl0impl.h | 11 ++---------
 unittest/gunit/mysys_my_rdtsc-t.cc  |  2 +-
 4 files changed, 9 insertions(+), 12 deletions(-)

diff --git a/cmake/boost.cmake b/cmake/boost.cmake
index 40c4d948c3af..9cd259c38bce 100644
--- a/cmake/boost.cmake
+++ b/cmake/boost.cmake
@@ -329,6 +329,9 @@ ELSE()
 ENDIF()
 
 IF(NOT WIN32)
+# Needed to use Boost header container_hash/hash.hpp in C++17
+  ADD_DEFINITIONS(-DBOOST_NO_CXX98_FUNCTION_BASE)
+
   FILE(GLOB_RECURSE BOOST_PATCHES_LIST
     RELATIVE ${BOOST_PATCHES_DIR}
     ${BOOST_PATCHES_DIR}/*.hpp
diff --git a/include/varlen_sort.h b/include/varlen_sort.h
index 80f97ada86f7..e45d4f0bbd45 100644
--- a/include/varlen_sort.h
+++ b/include/varlen_sort.h
@@ -184,8 +184,9 @@ namespace std {
 
 // Required for Iterator.
 template <>
-struct iterator_traits<varlen_iterator> : iterator_traits<varlen_element *> {};
-
+struct iterator_traits<varlen_iterator> : iterator_traits<varlen_element *> {
+  using reference = varlen_element;
+};
 }  // namespace std
 
 /*
diff --git a/storage/innobase/include/ddl0impl.h b/storage/innobase/include/ddl0impl.h
index 75028c81e021..cf0d1bd807d4 100644
--- a/storage/innobase/include/ddl0impl.h
+++ b/storage/innobase/include/ddl0impl.h
@@ -118,15 +118,8 @@ struct Fetch_sequence : public Context::FTS::Sequence {
 
 /** Physical row context. */
 struct Row {
-  /** Constructor. */
-  Row() = default;
-
-  Row(const Row &) = default;
-
-  /** Destructor. */
-  ~Row() = default;
-
-  /** Build a row from a raw record.
+  /** Build a row for the given index using the available clustered index
+  record (member m_rec).
   @param[in,out] ctx            DDL context.
   @param[in,out] index          Index the record belongs to.
   @param[in,out] heap           Heap to use for allocation.
diff --git a/unittest/gunit/mysys_my_rdtsc-t.cc b/unittest/gunit/mysys_my_rdtsc-t.cc
index 81462b09783d..221c508b701d 100644
--- a/unittest/gunit/mysys_my_rdtsc-t.cc
+++ b/unittest/gunit/mysys_my_rdtsc-t.cc
@@ -113,7 +113,7 @@ TEST_F(RDTimeStampCounter, TestCycle) {
   ulonglong t1 = my_timer_cycles();
   ulonglong t2;
   int i;
-  int backward = 0;
+  int backward [[maybe_unused]] = 0;
   int nonzero = 0;
 
   for (i = 0; i < LOOP_COUNT; i++) {