gtest installed with conan: undefined reference to `testing::internal::GetBoolAssertionFailureMessage` - c++

Question

I use cmake to build my project and conan to install Google Test as dependency:
conanfile.txt
[requires]
gtest/1.7.0#lasote/stable
[generators]
cmake
[imports]
bin, *.dll -> ./build/bin
lib, *.dylib* -> ./build/bin
CMakeLists.txt
PROJECT(MyTestingExample)
CMAKE_MINIMUM_REQUIRED(VERSION 2.8)
INCLUDE(conanbuildinfo.cmake)
CONAN_BASIC_SETUP()
ADD_EXECUTABLE(my_test test/my_test.cpp)
TARGET_LINK_LIBRARIES(my_test ${CONAN_LIBS})
test/my_test.cpp
#include <gtest/gtest.h>
#include <string>
TEST(MyTest, foobar) {
std::string foo("foobar");
std::string bar("foobar");
ASSERT_STREQ(foo.c_str(), bar.c_str()); // working
EXPECT_FALSE(false); // error
}
Build
$ conan install --build=missing
$ mkdir build && cd build
$ cmake .. && cmake --build .
I can use ASSERT_STREQ, but if I use EXPECT_FALSE I get an unexpected error:
my_test.cpp:(.text+0x1e1): undefined reference to `testing::internal::GetBoolAssertionFailureMessage[abi:cxx11](testing::AssertionResult const&, char const*, char const*, char const*)'
collect2: error: ld returned 1 exit status
What's wrong with my configuration?

Answer 1

The issue is that you are installing conan dependencies using the default settings (which is build type Release):
$ conan install --build=missing
# equivalent to
$ conan install -s build_type=Release ... --build=missing
The default settings can be seen in your conan.conf file
Then, you are using cmake in a nix system with the default build type which is Debug, which is a single-conf environment (opposed to multi-configuration Debug/Release environments, as Visual Studio), so when you are doing:
$ cmake .. && cmake --build .
# equivalent to
$ cmake .. -DCMAKE_BUILD_TYPE=Debug && cmake --build .
The incompatibility of Debug/Release build leads to that unresolved issue. So the solution would be to use the same build type that matches your installed dependencies:
$ cmake .. -DCMAKE_BUILD_TYPE=Release && cmake --build .
If using multi-configuration environments like Visual Studio, the correct way would be:
$ cmake .. && cmake --build . --config Release

Answer 2

On my side, I get this issue because being on Redhat 7 then with an old libstdc++.
Too old for conan default packages binaries/libraries.
I have fixed that by rebuilding gtest with '--build gtest' arg.