1 ### Generic Build Instructions
2
3 #### Setup
4
5 To build Google Test and your tests that use it, you need to tell your build
6 system where to find its headers and source files. The exact way to do it
7 depends on which build system you use, and is usually straightforward.
8
9 #### Build
10
11 Suppose you put Google Test in directory `${GTEST_DIR}`. To build it, create a
12 library build target (or a project as called by Visual Studio and Xcode) to
13 compile
14
15 ${GTEST_DIR}/src/gtest-all.cc
16
17 with `${GTEST_DIR}/include` in the system header search path and `${GTEST_DIR}`
18 in the normal header search path. Assuming a Linux-like system and gcc,
19 something like the following will do:
20
21 g++ -isystem ${GTEST_DIR}/include -I${GTEST_DIR} \
22 -pthread -c ${GTEST_DIR}/src/gtest-all.cc
23 ar -rv libgtest.a gtest-all.o
24
25 (We need `-pthread` as Google Test uses threads.)
26
27 Next, you should compile your test source file with `${GTEST_DIR}/include` in
28 the system header search path, and link it with gtest and any other necessary
29 libraries:
30
31 g++ -isystem ${GTEST_DIR}/include -pthread path/to/your_test.cc libgtest.a \
32 -o your_test
33
34 As an example, the make/ directory contains a Makefile that you can use to build
35 Google Test on systems where GNU make is available (e.g. Linux, Mac OS X, and
36 Cygwin). It doesn't try to build Google Test's own tests. Instead, it just
37 builds the Google Test library and a sample test. You can use it as a starting
38 point for your own build script.
39
40 If the default settings are correct for your environment, the following commands
41 should succeed:
42
43 cd ${GTEST_DIR}/make
44 make
45 ./sample1_unittest
46
47 If you see errors, try to tweak the contents of `make/Makefile` to make them go
48 away. There are instructions in `make/Makefile` on how to do it.
49
50 ### Using CMake
51
52 Google Test comes with a CMake build script (
53 [CMakeLists.txt](https://github.com/google/googletest/blob/master/CMakeLists.txt))
54 that can be used on a wide range of platforms ("C" stands for cross-platform.).
55 If you don't have CMake installed already, you can download it for free from
56 <http://www.cmake.org/>.
57
58 CMake works by generating native makefiles or build projects that can be used in
59 the compiler environment of your choice. You can either build Google Test as a
60 standalone project or it can be incorporated into an existing CMake build for
61 another project.
62
63 #### Standalone CMake Project
64
65 When building Google Test as a standalone project, the typical workflow starts
66 with:
67
68 mkdir mybuild # Create a directory to hold the build output.
69 cd mybuild
70 cmake ${GTEST_DIR} # Generate native build scripts.
71
72 If you want to build Google Test's samples, you should replace the last command
73 with
74
75 cmake -Dgtest_build_samples=ON ${GTEST_DIR}
76
77 If you are on a \*nix system, you should now see a Makefile in the current
78 directory. Just type 'make' to build gtest.
79
80 If you use Windows and have Visual Studio installed, a `gtest.sln` file and
81 several `.vcproj` files will be created. You can then build them using Visual
82 Studio.
83
84 On Mac OS X with Xcode installed, a `.xcodeproj` file will be generated.
85
86 #### Incorporating Into An Existing CMake Project
87
88 If you want to use gtest in a project which already uses CMake, then a more
89 robust and flexible approach is to build gtest as part of that project directly.
90 This is done by making the GoogleTest source code available to the main build
91 and adding it using CMake's `add_subdirectory()` command. This has the
92 significant advantage that the same compiler and linker settings are used
93 between gtest and the rest of your project, so issues associated with using
94 incompatible libraries (eg debug/release), etc. are avoided. This is
95 particularly useful on Windows. Making GoogleTest's source code available to the
96 main build can be done a few different ways:
97
98 * Download the GoogleTest source code manually and place it at a known
99 location. This is the least flexible approach and can make it more difficult
100 to use with continuous integration systems, etc.
101 * Embed the GoogleTest source code as a direct copy in the main project's
102 source tree. This is often the simplest approach, but is also the hardest to
103 keep up to date. Some organizations may not permit this method.
104 * Add GoogleTest as a git submodule or equivalent. This may not always be
105 possible or appropriate. Git submodules, for example, have their own set of
106 advantages and drawbacks.
107 * Use CMake to download GoogleTest as part of the build's configure step. This
108 is just a little more complex, but doesn't have the limitations of the other
109 methods.
110
111 The last of the above methods is implemented with a small piece of CMake code in
112 a separate file (e.g. `CMakeLists.txt.in`) which is copied to the build area and
113 then invoked as a sub-build _during the CMake stage_. That directory is then
114 pulled into the main build with `add_subdirectory()`. For example:
115
116 New file `CMakeLists.txt.in`:
117
118 ``` cmake
119 cmake_minimum_required(VERSION 2.8.2)
120
121 project(googletest-download NONE)
122
123 include(ExternalProject)
124 ExternalProject_Add(googletest
125 GIT_REPOSITORY https://github.com/google/googletest.git
126 GIT_TAG master
127 SOURCE_DIR "${CMAKE_BINARY_DIR}/googletest-src"
128 BINARY_DIR "${CMAKE_BINARY_DIR}/googletest-build"
129 CONFIGURE_COMMAND ""
130 BUILD_COMMAND ""
131 INSTALL_COMMAND ""
132 TEST_COMMAND ""
133 )
134 ```
135
136 Existing build's `CMakeLists.txt`:
137
138 ``` cmake
139 # Download and unpack googletest at configure time
140 configure_file(CMakeLists.txt.in googletest-download/CMakeLists.txt)
141 execute_process(COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}" .
142 RESULT_VARIABLE result
143 WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/googletest-download )
144 if(result)
145 message(FATAL_ERROR "CMake step for googletest failed: ${result}")
146 endif()
147 execute_process(COMMAND ${CMAKE_COMMAND} --build .
148 RESULT_VARIABLE result
149 WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/googletest-download )
150 if(result)
151 message(FATAL_ERROR "Build step for googletest failed: ${result}")
152 endif()
153
154 # Prevent overriding the parent project's compiler/linker
155 # settings on Windows
156 set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
157
158 # Add googletest directly to our build. This defines
159 # the gtest and gtest_main targets.
160 add_subdirectory(${CMAKE_BINARY_DIR}/googletest-src
161 ${CMAKE_BINARY_DIR}/googletest-build
162 EXCLUDE_FROM_ALL)
163
164 # The gtest/gtest_main targets carry header search path
165 # dependencies automatically when using CMake 2.8.11 or
166 # later. Otherwise we have to add them here ourselves.
167 if (CMAKE_VERSION VERSION_LESS 2.8.11)
168 include_directories("${gtest_SOURCE_DIR}/include")
169 endif()
170
171 # Now simply link against gtest or gtest_main as needed. Eg
172 add_executable(example example.cpp)
173 target_link_libraries(example gtest_main)
174 add_test(NAME example_test COMMAND example)
175 ```
176
177 Note that this approach requires CMake 2.8.2 or later due to its use of the
178 `ExternalProject_Add()` command. The above technique is discussed in more detail
179 in [this separate article](http://crascit.com/2015/07/25/cmake-gtest/) which
180 also contains a link to a fully generalized implementation of the technique.
181
182 ##### Visual Studio Dynamic vs Static Runtimes
183
184 By default, new Visual Studio projects link the C runtimes dynamically but
185 Google Test links them statically. This will generate an error that looks
186 something like the following: gtest.lib(gtest-all.obj) : error LNK2038: mismatch
187 detected for 'RuntimeLibrary': value 'MTd_StaticDebug' doesn't match value
188 'MDd_DynamicDebug' in main.obj
189
190 Google Test already has a CMake option for this: `gtest_force_shared_crt`
191
192 Enabling this option will make gtest link the runtimes dynamically too, and
193 match the project in which it is included.
194
195 ### Legacy Build Scripts
196
197 Before settling on CMake, we have been providing hand-maintained build
198 projects/scripts for Visual Studio, Xcode, and Autotools. While we continue to
199 provide them for convenience, they are not actively maintained any more. We
200 highly recommend that you follow the instructions in the above sections to
201 integrate Google Test with your existing build system.
202
203 If you still need to use the legacy build scripts, here's how:
204
205 The msvc\ folder contains two solutions with Visual C++ projects. Open the
206 `gtest.sln` or `gtest-md.sln` file using Visual Studio, and you are ready to
207 build Google Test the same way you build any Visual Studio project. Files that
208 have names ending with -md use DLL versions of Microsoft runtime libraries (the
209 /MD or the /MDd compiler option). Files without that suffix use static versions
210 of the runtime libraries (the /MT or the /MTd option). Please note that one must
211 use the same option to compile both gtest and the test code. If you use Visual
212 Studio 2005 or above, we recommend the -md version as /MD is the default for new
213 projects in these versions of Visual Studio.
214
215 On Mac OS X, open the `gtest.xcodeproj` in the `xcode/` folder using Xcode.
216 Build the "gtest" target. The universal binary framework will end up in your
217 selected build directory (selected in the Xcode "Preferences..." -> "Building"
218 pane and defaults to xcode/build). Alternatively, at the command line, enter:
219
220 xcodebuild
221
222 This will build the "Release" configuration of gtest.framework in your default
223 build location. See the "xcodebuild" man page for more information about
224 building different configurations and building in different locations.
225
226 If you wish to use the Google Test Xcode project with Xcode 4.x and above, you
227 need to either:
228
229 * update the SDK configuration options in xcode/Config/General.xconfig.
230 Comment options `SDKROOT`, `MACOS_DEPLOYMENT_TARGET`, and `GCC_VERSION`. If
231 you choose this route you lose the ability to target earlier versions of
232 MacOS X.
233 * Install an SDK for an earlier version. This doesn't appear to be supported
234 by Apple, but has been reported to work
235 (http://stackoverflow.com/questions/5378518).
236
237 ### Tweaking Google Test
238
239 Google Test can be used in diverse environments. The default configuration may
240 not work (or may not work well) out of the box in some environments. However,
241 you can easily tweak Google Test by defining control macros on the compiler
242 command line. Generally, these macros are named like `GTEST_XYZ` and you define
243 them to either 1 or 0 to enable or disable a certain feature.
244
245 We list the most frequently used macros below. For a complete list, see file
246 [include/gtest/internal/gtest-port.h](https://github.com/google/googletest/blob/master/include/gtest/internal/gtest-port.h).
247
248 ### Choosing a TR1 Tuple Library
249
250 Some Google Test features require the C++ Technical Report 1 (TR1) tuple
251 library, which is not yet available with all compilers. The good news is that
252 Google Test implements a subset of TR1 tuple that's enough for its own need, and
253 will automatically use this when the compiler doesn't provide TR1 tuple.
254
255 Usually you don't need to care about which tuple library Google Test uses.
256 However, if your project already uses TR1 tuple, you need to tell Google Test to
257 use the same TR1 tuple library the rest of your project uses, or the two tuple
258 implementations will clash. To do that, add
259
260 -DGTEST_USE_OWN_TR1_TUPLE=0
261
262 to the compiler flags while compiling Google Test and your tests. If you want to
263 force Google Test to use its own tuple library, just add
264
265 -DGTEST_USE_OWN_TR1_TUPLE=1
266
267 to the compiler flags instead.
268
269 If you don't want Google Test to use tuple at all, add
270
271 -DGTEST_HAS_TR1_TUPLE=0
272
273 and all features using tuple will be disabled.
274
275 ### Multi-threaded Tests
276
277 Google Test is thread-safe where the pthread library is available. After
278 `#include "gtest/gtest.h"`, you can check the `GTEST_IS_THREADSAFE` macro to see
279 whether this is the case (yes if the macro is `#defined` to 1, no if it's
280 undefined.).
281
282 If Google Test doesn't correctly detect whether pthread is available in your
283 environment, you can force it with
284
285 -DGTEST_HAS_PTHREAD=1
286
287 or
288
289 -DGTEST_HAS_PTHREAD=0
290
291 When Google Test uses pthread, you may need to add flags to your compiler and/or
292 linker to select the pthread library, or you'll get link errors. If you use the
293 CMake script or the deprecated Autotools script, this is taken care of for you.
294 If you use your own build script, you'll need to read your compiler and linker's
295 manual to figure out what flags to add.
296
297 ### As a Shared Library (DLL)
298
299 Google Test is compact, so most users can build and link it as a static library
300 for the simplicity. You can choose to use Google Test as a shared library (known
301 as a DLL on Windows) if you prefer.
302
303 To compile *gtest* as a shared library, add
304
305 -DGTEST_CREATE_SHARED_LIBRARY=1
306
307 to the compiler flags. You'll also need to tell the linker to produce a shared
308 library instead - consult your linker's manual for how to do it.
309
310 To compile your *tests* that use the gtest shared library, add
311
312 -DGTEST_LINKED_AS_SHARED_LIBRARY=1
313
314 to the compiler flags.
315
316 Note: while the above steps aren't technically necessary today when using some
317 compilers (e.g. GCC), they may become necessary in the future, if we decide to
318 improve the speed of loading the library (see
319 <http://gcc.gnu.org/wiki/Visibility> for details). Therefore you are recommended
320 to always add the above flags when using Google Test as a shared library.
321 Otherwise a future release of Google Test may break your build script.
322
323 ### Avoiding Macro Name Clashes
324
325 In C++, macros don't obey namespaces. Therefore two libraries that both define a
326 macro of the same name will clash if you `#include` both definitions. In case a
327 Google Test macro clashes with another library, you can force Google Test to
328 rename its macro to avoid the conflict.
329
330 Specifically, if both Google Test and some other code define macro FOO, you can
331 add
332
333 -DGTEST_DONT_DEFINE_FOO=1
334
335 to the compiler flags to tell Google Test to change the macro's name from `FOO`
336 to `GTEST_FOO`. Currently `FOO` can be `FAIL`, `SUCCEED`, or `TEST`. For
337 example, with `-DGTEST_DONT_DEFINE_TEST=1`, you'll need to write
338
339 GTEST_TEST(SomeTest, DoesThis) { ... }
340
341 instead of
342
343 TEST(SomeTest, DoesThis) { ... }
344
345 in order to define a test.