Cmake 自動默認為 gcc-5

Question

我正在嘗試使用 cmake 編譯 amber 工具。我使用的是 ubuntu Ubuntu 16.04.7 LTS，默認版本為 gcc gcc-5 和 g++5，而 amber 工具至少需要 gcc-6。 我已經安裝了 gcc-8 和 g++8，並使用 CMAKE_C_COMPILER 和 CMAKE_CXX_COMPILER 指定了它。 cmake使用的命令是下面的命令：

cmake $AMBER_PREFIX/amber22_src \
-DCMAKE_INSTALL_PREFIX=$AMBER_PREFIX/amber22 \
-DCOMPILER=GNU \
-DMPI=FALSE -DCUDA=TRUE -DINSTALL_TESTS=TRUE \
-DDOWNLOAD_MINICONDA=TRUE \
-DCMAKE_C_COMPILER=/usr/bin/gcc-8 -DCMAKE_CXX_COMPILER=/usr/bin/g++-8 \

即使指定了 gcc g++，我也會收到以下錯誤：

-- Starting configuration of Amber version 22.0.0...
-- CMake Version: 3.14.0
-- For how to use this build system, please read this wiki:
--     http://ambermd.org/pmwiki/pmwiki.php/Main/CMake
-- For a list of important CMake variables, check here:
--     http://ambermd.org/pmwiki/pmwiki.php/Main/CMake-Common-Options
-- **************************************************************************
-- Setting C compiler to gcc
-- Setting CXX compiler to g++
-- Setting Fortran compiler to gfortran
-- Amber source not found, only building AmberTools
-- The C compiler identification is GNU 5.4.0
-- The CXX compiler identification is GNU 5.4.0
-- The Fortran compiler identification is GNU 5.4.0
-- Check for working C compiler: /usr/bin/gcc
-- Check for working C compiler: /usr/bin/gcc -- works
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Detecting C compile features
-- Detecting C compile features - done
-- Check for working CXX compiler: /usr/bin/g++
-- Check for working CXX compiler: /usr/bin/g++ -- works
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Check for working Fortran compiler: /usr/bin/gfortran
-- Check for working Fortran compiler: /usr/bin/gfortran  -- works
-- Detecting Fortran compiler ABI info
-- Detecting Fortran compiler ABI info - done
-- Checking whether /usr/bin/gfortran supports Fortran 90
-- Checking whether /usr/bin/gfortran supports Fortran 90 -- yes
-- 
************************************************************
Error: Amber requires at least g++-6.0
See https://ambermd.org/Installation.php for more info
************************************************************
-- 
CMake Error at cmake/VerifyCompilerConfig.cmake:30 (message):
Call Stack (most recent call first):
  cmake/AmberBuildSystem2ndInit.cmake:30 (include)
  CMakeLists.txt:111 (include)


-- Configuring incomplete, errors occurred!
See also "/media/gpu-1/GPU_1_2TB/Ambertools22/amber22_src/build/CMakeFiles/CMakeOutput.log".
You have changed variables that require your cache to be deleted.
Configure will be re-run and you may have to reset some variables.
The following variables have changed:
CMAKE_C_COMPILER= /usr/bin/gcc-8
CMAKE_CXX_COMPILER= /usr/bin/g++-8

-- Generating done
CMake Warning:
  Manually-specified variables were not used by the project:

    DOWNLOAD_MINICONDA
    MPI


-- Build files have been written to: /media/gpu-1/GPU_1_2TB/Ambertools22/amber22_src/build

If the cmake build report looks OK, you should now do the following:

    make install
    source /media/gpu-1/GPU_1_2TB/Ambertools22/amber22/amber.sh

謝謝

Answer 1

我不會將其稱為 CMake 的問題，而是 Amber 通過 CMake 執行編譯器控制的方式，這很可能是通過采用環境變量 $PATH 中出現的第一個編譯器來執行的。

如果你仍然想編譯它，我可以建議兩種便宜的方法：

• 使用update-alternatives package，更改“系統默認值”gcc 和 g++
• 在 PATH 中添加一個路徑export PATH=absolute/path/to/a/folder:$PATH ，並在此路徑中放置兩個符號鏈接，分別稱為 gcc 和 g++，指向 gcc-8 和 g++-8

Answer 2

據此，您仍在使用在設置新的C和CXX編譯器之前生成的現有緩存文件。

You have changed variables that require your cache to be deleted.
Configure will be re-run and you may have to reset some variables.
The following variables have changed:
CMAKE_C_COMPILER= /usr/bin/gcc-8
CMAKE_CXX_COMPILER= /usr/bin/g++-8

基於cmake $AMBER_PREFIX/amber22_src ，您正在從構建文件夾中運行它。 一般來說，我建議使用語法cmake -S[source] -B[build] 。 您當前的工作目錄應該被完全刪除。 一旦你這樣做，重新運行你的cmake命令，它應該被正確設置。

如果它不起作用，您可以通過添加來進行健全性檢查

set(CMAKE_C_COMPILER [path_to_C])
set(CMAKE_CXX_COMPILER [path_to_CXX])

請務必將其放在 CMAKELISTS 文件的開頭，即在任何project()行之前。

編輯：你也聽說過 docker 嗎？ 它是為使用遺留工具創建特殊封閉環境的絕佳工具。