Ubuntu 20.04 安装 OpenFOAM-v1712

李东岳

首先，需要安装老版本的g++/gcc:

sudo gedit /etc/apt/sources.list

添加下面两行：

deb http://dk.archive.ubuntu.com/ubuntu/ xenial main
deb http://dk.archive.ubuntu.com/ubuntu/ xenial universe

然后：

sudo apt-get update
sudo apt-get install g++-5 gcc-5
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-5 100
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-5 100

现在，就应该默认选择gcc-5，g++-5了。接着，顺着编译OpenFOAM-v1712就好。

查看已有的版本：

ls /usr/bin/gcc*
ls /usr/bin/g++*

选择版本：

sudo update-alternatives --config gcc
sudo update-alternatives --config g++

李东岳

另外，低版本Ubuntu安装高版本gcc：

sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt update
sudo apt install gcc-9  g++-9

如果出现unable to fetch这种错误，再运行一下sudo apt install gcc-9 g++-9

chengan.wang

李老师您好，
我按照您的提示：

sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-5 100

目前默认gcc-5

gcc (Ubuntu 5.3.1-14ubuntu2) 5.3.1 20160413
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

我想切换回g9，用命令

sudo update-alternatives --config gcc

得到：

There is only one alternative in link group gcc (providing /usr/bin/gcc): /usr/bin/gcc-5
Nothing to configure.

没有切换提示，咋办？

我用命令

ls /usr/bin/gcc*

/usr/bin/gcc    /usr/bin/gcc-ar    /usr/bin/gcc-nm    /usr/bin/gcc-ranlib
/usr/bin/gcc-5  /usr/bin/gcc-ar-5  /usr/bin/gcc-nm-5  /usr/bin/gcc-ranlib-5
/usr/bin/gcc-9  /usr/bin/gcc-ar-9  /usr/bin/gcc-nm-9  /usr/bin/gcc-ranlib-9

应该是g9也在的，不知道为啥不能切换，跟百度不一样

李东岳

@chengan-wang 我有时候也遇到过这个问题来回操作几次就解决了目前不知道原因不过还可以不算麻烦

chengan.wang

@李东岳谢谢李老师，编译器最后安装成功了，也能切换，但是这种方法安装2.4.0版本还是不对

李东岳

@chengan-wang 2.4版本需要安装gcc/g++-4.8 你试试

chengan.wang

@李东岳李老师，我安装官网的方法https://openfoam.org/download/2-4-0-source/，还是不行呀，编译出错。又参考了http://openfoamwiki.net/index.php/Installation/Linux/OpenFOAM-2.4.0/Ubuntu#Ubuntu_18.04，ubuntu18.04的安装方法，也不行。

李东岳

@chengan-wang 你用的低版本g++么，我装的更低版本的openfoam-2.1都没问题呢

chengan.wang

@李东岳李老师好，我分别用了gcc-4.7、g++-4.7；gcc-4.8、g++-4.8；gcc-5.0、g++-5.0在ubuntu20.04安装of2.4.0，按照官网和wiki都不行。您的安装流程能分享一下么？

李东岳

@chengan-wang log提示什么错误

chengan.wang

@李东岳李老师，编译过程出现了很多错误：

== Generating build files ==
Configuring libCGAL
-- Requested component: MPFR
-- Requested component: GMP
libCGAL is configured
-- Sources for CGAL component library 'CGAL_Core/CMakeLists.txt' detected
CMake Error at src/CMakeLists.txt:81 (add_subdirectory):
  add_subdirectory given source
  "/home/chengan/OpenFOAM/ThirdParty-2.4.0/CGAL-4.6/src/CGAL_Core/CMakeLists.txt"
  which is not an existing directory.
Call Stack (most recent call first):
  src/CMakeLists.txt:140 (configure_component)


-- Sources for CGAL component library 'CGAL_ImageIO/CMakeLists.txt' detected
CMake Error at src/CMakeLists.txt:81 (add_subdirectory):
  add_subdirectory given source
  "/home/chengan/OpenFOAM/ThirdParty-2.4.0/CGAL-4.6/src/CGAL_ImageIO/CMakeLists.txt"
  which is not an existing directory.
Call Stack (most recent call first):
  src/CMakeLists.txt:140 (configure_component)


-- Sources for CGAL component library 'CGAL_Qt3/CMakeLists.txt' detected
CMake Error at src/CMakeLists.txt:81 (add_subdirectory):
  add_subdirectory given source
  "/home/chengan/OpenFOAM/ThirdParty-2.4.0/CGAL-4.6/src/CGAL_Qt3/CMakeLists.txt"
  which is not an existing directory.
Call Stack (most recent call first):
  src/CMakeLists.txt:140 (configure_component)


-- Sources for CGAL component library 'CGAL_Qt4/CMakeLists.txt' detected
CMake Error at src/CMakeLists.txt:81 (add_subdirectory):
  add_subdirectory given source
  "/home/chengan/OpenFOAM/ThirdParty-2.4.0/CGAL-4.6/src/CGAL_Qt4/CMakeLists.txt"
  which is not an existing directory.
Call Stack (most recent call first):
  src/CMakeLists.txt:140 (configure_component)


-- Sources for CGAL component libraries 'CGAL_Core/CMakeLists.txt;CGAL_ImageIO/CMakeLists.txt;CGAL_Qt3/CMakeLists.txt;CGAL_Qt4/CMakeLists.txt' detected
== Generating build files (DONE) ==

-- Configuring incomplete, errors occurred!
See also "/home/chengan/OpenFOAM/ThirdParty-2.4.0/build/linux64Gcc/CGAL-4.6/CMakeFiles/CMakeOutput.log".
See also "/home/chengan/OpenFOAM/ThirdParty-2.4.0/build/linux64Gcc/CGAL-4.6/CMakeFiles/CMakeError.log".
+ exit 1

还有很多这样的：

/usr/bin/ld: /home/chengan/OpenFOAM/OpenFOAM-2.4.0/platforms/linux64GccDPOpt/lib/libtriSurface.so: undefined reference to `yyFlexLexer::yywrap()'
collect2: error: ld returned 1 exit status
make[2]: *** [/home/chengan/OpenFOAM/OpenFOAM-2.4.0/wmake/Makefile:150: /home/chengan/OpenFOAM/OpenFOAM-2.4.0/platforms/linux64GccDPOpt/bin/interMixingFoam] Error 1
make[1]: *** [/home/chengan/OpenFOAM/OpenFOAM-2.4.0/wmake/MakefileApps:39: interFoam] Error 2
make[1]: Target 'application' not remade because of errors.
make: *** [/home/chengan/OpenFOAM/OpenFOAM-2.4.0/wmake/MakefileApps:39: multiphase] Error 2
make: Target 'application' not remade because of errors.

log文件如下：
log.tar.xz
希望李老师能百忙之中指点一下！

李东岳

@chengan-wang

第三方包先不用管你先在终端输入这个编译openfoam应该没问题了

https://www.cfd-china.com/topic/4859/yyflex-error

chengan.wang

@李东岳谢谢李老师，不过命令报错了

chengan@chengan-MS-7C80:~/OpenFOAM/OpenFOAM-2.4.0$ find src applications -name "*.L" -type f | xargs sed -i -e 's=(YY_FLEX_SUBMINOR_VERSION)=YY_FLEX_MINOR_VERSION < 6 && \1='
sed: -e expression #1, char 61: invalid reference \1 on `s' command's RHS

chengan.wang

@李东岳李老师，我在wiki上找到命令如下：

find src applications -name "*.L" -type f | xargs sed -i -e 's=\(YY\_FLEX\_SUBMINOR\_VERSION\)=YY_FLEX_MINOR_VERSION < 6 \&\& \1='

这个可以用。

最终我选择gcc-4.8、g++-4.8编译，目前可以运行icoFoam cavity 算例，似乎编译成功了，但是log文件有2522个错误，不知道算是编译成功了没有，还是可以将就着用？

log.zip

李东岳

@chengan-wang 没关系，主要是其中做foamQuad网格的，这个用得少

chengan.wang

@李东岳谢谢李老师

李东岳

@chengan-wang 为什么要用openfoam2.4.?

chengan.wang

@李东岳之前用了很久，很多求解器也是基于这个版本改的