fix build branch cpp17 on Kunpeng-920 where std::numeric_limits<long double>::digits10 == 33, instead of 18 on aarch64.

[qingzhongli]

Build branch cpp17 fail on aarch64, reproduce step:

• build enviroment:

  
  [root@ecs-2bfc ~]# cat /etc/os-release 
  NAME="openEuler"
  VERSION="20.03 (LTS)"
  ID="openEuler"
  VERSION_ID="20.03"
  PRETTY_NAME="openEuler 20.03 (LTS)"
  ANSI_COLOR="0;31"

[root@ecs-2bfc ~]# uname -a Linux ecs-2bfc 4.19.90-2110.8.0.0119.oe1.aarch64 #1 SMP Wed Oct 27 10:35:51 UTC 2021 aarch64 aarch64 aarch64 GNU/Linux [root@ecs-2bfc ~]# lscpu Architecture: aarch64 CPU op-mode(s): 64-bit Byte Order: Little Endian CPU(s): 2 On-line CPU(s) list: 0,1 Thread(s) per core: 1 Core(s) per socket: 2 Socket(s): 1 NUMA node(s): 1 Vendor ID: HiSilicon Model: 0 Model name: Kunpeng-920 Stepping: 0x1 CPU max MHz: 2400.0000 CPU min MHz: 2400.0000 BogoMIPS: 200.00 L1d cache: 128 KiB L1i cache: 128 KiB L2 cache: 1 MiB L3 cache: 32 MiB NUMA node0 CPU(s): 0,1 Vulnerability Itlb multihit: Not affected Vulnerability L1tf: Not affected Vulnerability Mds: Not affected Vulnerability Meltdown: Not affected Vulnerability Spec store bypass: Not affected Vulnerability Spectre v1: Mitigation; __user pointer sanitization Vulnerability Spectre v2: Not affected Vulnerability Srbds: Not affected Vulnerability Tsx async abort: Not affected Flags: fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp cpuid asimdrdm jscvt fcma dcpop asimddp asimdfhm [root@ecs-2bfc ~]#

* install the necessary software

yum install wget git gcc gcc-c++ make -y wget -O cmake-3.25.2.tar.gz "https://github.com/Kitware/CMake/releases/download/v3.25.2/cmake-3.25.2-linux-aarch64.tar.gz" tar -zxf cmake-3.25.2.tar.gz export PATH="$PATH:/root/cmake-3.25.2-linux-aarch64/bin"

* compile process:

[root@ecs-2bfc ~]# git clone https://github.com/chenshuo/muduo Cloning into 'muduo'... remote: Enumerating objects: 8424, done. remote: Counting objects: 100% (250/250), done. remote: Compressing objects: 100% (48/48), done. remote: Total 8424 (delta 214), reused 202 (delta 202), pack-reused 8174 Receiving objects: 100% (8424/8424), 1.76 MiB | 3.32 MiB/s, done. Resolving deltas: 100% (5244/5244), done. [root@ecs-2bfc ~]# cd muduo [root@ecs-2bfc muduo]# git checkout cpp17 Branch 'cpp17' set up to track remote branch 'cpp17' from 'origin'. Switched to a new branch 'cpp17' [root@ecs-2bfc muduo]# ./build.sh ++ pwd

• SOURCE_DIR=/root/muduo
• BUILD_DIR=../build
• BUILD_TYPE=release
• INSTALL_DIR=../release-install-cpp17
• CXX=g++
• ln -sf ../build/release-cpp17/compile_commands.json
• mkdir -p ../build/release-cpp17
• cd ../build/release-cpp17

• cmake -DCMAKE_BUILD_TYPE=release -DCMAKE_INSTALL_PREFIX=../release-install-cpp17 -DCMAKE_EXPORT_COMPILE_COMMANDS=ON /root/muduo CMake Deprecation Warning at CMakeLists.txt:1 (cmake_minimum_required): Compatibility with CMake < 2.8.12 will be removed from a future version of CMake.

  Update the VERSION argument value or use a ... suffix to tell CMake that the project does not need compatibility with older versions.

-- Could NOT find Boost (missing: Boost_INCLUDE_DIR) -- Could NOT find Protobuf (missing: Protobuf_LIBRARIES Protobuf_INCLUDE_DIR) -- Could NOT find CURL (missing: CURL_LIBRARY CURL_INCLUDE_DIR) -- Could NOT find ZLIB (missing: ZLIB_LIBRARY ZLIB_INCLUDE_DIR) -- CXX_FLAGS = -g -DCHECK_PTHREAD_RETURN_VALUE -D_FILE_OFFSET_BITS=64 -Wall -Wextra -Werror -Wconversion -Wno-unused-parameter -Wold-style-cast -Woverloaded-virtual -Wpointer-arith -Wshadow -Wwrite-strings -march=native -std=c++17 -rdynamic -O2 -DNDEBUG -- Configuring done -- Generating done -- Build files have been written to: /root/build/release-cpp17

• make [ 0%] Building CXX object muduo/base/CMakeFiles/muduo_base.dir/AsyncLogging.cc.o [ 0%] Building CXX object muduo/base/CMakeFiles/muduo_base.dir/Condition.cc.o [ 1%] Building CXX object muduo/base/CMakeFiles/muduo_base.dir/CountDownLatch.cc.o [ 1%] Building CXX object muduo/base/CMakeFiles/muduo_base.dir/CurrentThread.cc.o [ 1%] Building CXX object muduo/base/CMakeFiles/muduo_base.dir/Date.cc.o [ 1%] Building CXX object muduo/base/CMakeFiles/muduo_base.dir/Exception.cc.o [ 2%] Building CXX object muduo/base/CMakeFiles/muduo_base.dir/FileUtil.cc.o [ 2%] Building CXX object muduo/base/CMakeFiles/muduo_base.dir/LogFile.cc.o [ 2%] Building CXX object muduo/base/CMakeFiles/muduo_base.dir/Logging.cc.o [ 3%] Building CXX object muduo/base/CMakeFiles/muduo_base.dir/LogStream.cc.o /root/muduo/muduo/base/LogStream.cc: In member function ‘void muduo::LogStream::staticCheck()’: /root/muduo/muduo/base/LogStream.cc:107:3: error: static assertion failed: kMaxNumericSize is large enough static_assert(kMaxNumericSize - 10 > std::numeric_limits::digits10, ^~~~~ make[2]: [muduo/base/CMakeFiles/muduo_base.dir/build.make:202: muduo/base/CMakeFiles/muduo_base.dir/LogStream.cc.o] Error 1 make[1]: [CMakeFiles/Makefile2:1057: muduo/base/CMakeFiles/muduo_base.dir/all] Error 2 make: *** [Makefile:146: all] Error 2 [root@ecs-2bfc muduo]#

[ggandycong]

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