c++ - 使用 Google Test 编译程序时出现 "g++ is not a full path"

Question

我正在尝试使用 g++ 编译一个使用 Google Test 作为子模块的程序。这是我尝试过的:

git init testgoogletest
cd testgoogletest
git submodule add https://github.com/google/googletest.git

然后，我创建了一个 CMakeLists.txt 包含:

cmake_minimum_required (VERSION 3.5.1)
project(try_googletest)

set(CMAKE_CXX_COMPILER g++)

set(VARIABLE_INCLUDE_DIR "${gtest_SOURCE_DIR}/include" "${gmock_SOURCE_DIR}/include")
add_subdirectory(../googletest gtest)

target_include_directories(gmock_main SYSTEM BEFORE INTERFACE
    "${gtest_SOURCE_DIR}/include" "${gmock_SOURCE_DIR}/include")

add_executable(my_executable test.cpp)
target_link_libraries(my_executable PRIVATE gmock_main)

还有一个名为 test.cpp 的文件，其中包含:

#include "gtest/gtest.h"
#include "gmock/gmock.h"

TEST(SimpleTest, works) {
    EXPECT_TRUE(true);
}

然后，我运行了命令:

mkdir build
cd build
cmake ..

我得到了以下 fatal error :

CMake Error at (personal path)/googletest/CMakeLists.txt:7 (project):
  The CMAKE_CXX_COMPILER:

    g++

  is not a full path and was not found in the PATH.

  Tell CMake where to find the compiler by setting either the environment
  variable "CXX" or the CMake cache entry CMAKE_CXX_COMPILER to the full path
  to the compiler, or to the compiler name if it is in the PATH.

然而，当我运行 which g++ 时，我得到了 /usr/bin/g++，这意味着编译器名称在 PATH 中并且 CMake 应该找到它。我什至尝试了以下方法:

• 删除 Google Test 并将 test.cpp 替换为空的 main，这非常有效，这意味着问题出在 Google Test
• 将CMakeLists.txt中的g++替换为/usr/bin/g++，在运行cmake ..时会产生无限大的周期性输出

我的问题是:

• 为什么会出现这些错误？
• 是否存在解决方案，或者我真的需要忘掉 CMAKE_CXX_COMPILER 而改用 CXX？

Answer 1

我按照你的步骤做了。我们确实得到了一个无限循环，并且输出如下:

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_CXX_COMPILER= /usr/bin/c++

按以下方式更改 CMakeLists.txt 文件中的 set 似乎可以解决此问题:

set(CMAKE_CXX_COMPILER /usr/bin/c++)