Rocksdb 8.6.7 and Clang 16 upgrade

CMakeLists.txt

@@ -491,18 +491,13 @@ set(WITH_TOOLS
     CACHE BOOL "" FORCE)
 if(ENABLE_AVX2)
   set(PORTABLE
-      OFF
+      0
       CACHE BOOL "" FORCE)
 else()
   set(PORTABLE
-      ON
+      1
       CACHE BOOL "" FORCE)
 endif()
-set(FAIL_ON_WARNINGS
-    OFF
-    CACHE BOOL "") # Ignore unreachable code warning in merging_iterator.cc
-                   # RocksDB v7.8.3 on Windows
-                   # https://github.com/facebook/rocksdb/issues/11072
 add_subdirectory(submodules/rocksdb EXCLUDE_FROM_ALL)
 
 include_directories(cpptoml/include)

ci/prepare/linux/prepare-clang.sh

@@ -1,17 +1,15 @@
 #!/bin/bash
 set -euo pipefail
 
-apt-get update -qq && apt-get install -yqq \
-clang \
-lldb
+CLANG_VERSION=16
 
-export CXX=/usr/bin/clang++
-export CC=/usr/bin/clang
-update-alternatives --install /usr/bin/cc cc /usr/bin/clang 100
-update-alternatives --install /usr/bin/c++ c++ /usr/bin/clang++ 100
+# TODO: Verify integrity (at this time, the clang build is not used for any production artifacts)
+curl -O https://apt.llvm.org/llvm.sh && chmod +x llvm.sh && ./llvm.sh $CLANG_VERSION
 
-# workaround to get a path that can be easily passed into cmake for
-# BOOST_STACKTRACE_BACKTRACE_INCLUDE_FILE
-# see https://www.boost.org/doc/libs/1_70_0/doc/html/stacktrace/configuration_and_build.html#stacktrace.configuration_and_build.f3
+update-alternatives --install /usr/bin/cc cc /usr/bin/clang-$CLANG_VERSION 100
+update-alternatives --install /usr/bin/c++ c++ /usr/bin/clang++-$CLANG_VERSION 100
+update-alternatives --install /usr/bin/lldb lldb /usr/bin/lldb-$CLANG_VERSION 100
 
+# Workaround to get a path that can be easily passed into cmake for BOOST_STACKTRACE_BACKTRACE_INCLUDE_FILE
+# See https://www.boost.org/doc/libs/1_70_0/doc/html/stacktrace/configuration_and_build.html#stacktrace.configuration_and_build.f3
 backtrace_file=$(find /usr/lib/gcc/ -name 'backtrace.h' | head -n 1) && test -f $backtrace_file && ln -s $backtrace_file /tmp/backtrace.h