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diff --git a/graphics/asymptote/LspCpp/third_party/uri/deps/docs/pkgconfig.md b/graphics/asymptote/LspCpp/third_party/uri/deps/docs/pkgconfig.md deleted file mode 100644 index 18a2546a38..0000000000 --- a/graphics/asymptote/LspCpp/third_party/uri/deps/docs/pkgconfig.md +++ /dev/null @@ -1,148 +0,0 @@ -## Using GoogleTest from various build systems - -GoogleTest comes with pkg-config files that can be used to determine all -necessary flags for compiling and linking to GoogleTest (and GoogleMock). -Pkg-config is a standardised plain-text format containing - -* the includedir (-I) path -* necessary macro (-D) definitions -* further required flags (-pthread) -* the library (-L) path -* the library (-l) to link to - -All current build systems support pkg-config in one way or another. For all -examples here we assume you want to compile the sample -`samples/sample3_unittest.cc`. - -### CMake - -Using `pkg-config` in CMake is fairly easy: - -```cmake -cmake_minimum_required(VERSION 3.0) - -cmake_policy(SET CMP0048 NEW) -project(my_gtest_pkgconfig VERSION 0.0.1 LANGUAGES CXX) - -find_package(PkgConfig) -pkg_search_module(GTEST REQUIRED gtest_main) - -add_executable(testapp samples/sample3_unittest.cc) -target_link_libraries(testapp ${GTEST_LDFLAGS}) -target_compile_options(testapp PUBLIC ${GTEST_CFLAGS}) - -include(CTest) -add_test(first_and_only_test testapp) -``` - -It is generally recommended that you use `target_compile_options` + `_CFLAGS` -over `target_include_directories` + `_INCLUDE_DIRS` as the former includes not -just -I flags (GoogleTest might require a macro indicating to internal headers -that all libraries have been compiled with threading enabled. In addition, -GoogleTest might also require `-pthread` in the compiling step, and as such -splitting the pkg-config `Cflags` variable into include dirs and macros for -`target_compile_definitions()` might still miss this). The same recommendation -goes for using `_LDFLAGS` over the more commonplace `_LIBRARIES`, which happens -to discard `-L` flags and `-pthread`. - -### Help! pkg-config can't find GoogleTest! - -Let's say you have a `CMakeLists.txt` along the lines of the one in this -tutorial and you try to run `cmake`. It is very possible that you get a failure -along the lines of: - -``` --- Checking for one of the modules 'gtest_main' -CMake Error at /usr/share/cmake/Modules/FindPkgConfig.cmake:640 (message): - None of the required 'gtest_main' found -``` - -These failures are common if you installed GoogleTest yourself and have not -sourced it from a distro or other package manager. If so, you need to tell -pkg-config where it can find the `.pc` files containing the information. Say you -installed GoogleTest to `/usr/local`, then it might be that the `.pc` files are -installed under `/usr/local/lib64/pkgconfig`. If you set - -``` -export PKG_CONFIG_PATH=/usr/local/lib64/pkgconfig -``` - -pkg-config will also try to look in `PKG_CONFIG_PATH` to find `gtest_main.pc`. - -### Using pkg-config in a cross-compilation setting - -Pkg-config can be used in a cross-compilation setting too. To do this, let's -assume the final prefix of the cross-compiled installation will be `/usr`, and -your sysroot is `/home/MYUSER/sysroot`. Configure and install GTest using - -``` -mkdir build && cmake -DCMAKE_INSTALL_PREFIX=/usr .. -``` - -Install into the sysroot using `DESTDIR`: - -``` -make -j install DESTDIR=/home/MYUSER/sysroot -``` - -Before we continue, it is recommended to **always** define the following two -variables for pkg-config in a cross-compilation setting: - -``` -export PKG_CONFIG_ALLOW_SYSTEM_CFLAGS=yes -export PKG_CONFIG_ALLOW_SYSTEM_LIBS=yes -``` - -otherwise `pkg-config` will filter `-I` and `-L` flags against standard prefixes -such as `/usr` (see https://bugs.freedesktop.org/show_bug.cgi?id=28264#c3 for -reasons why this stripping needs to occur usually). - -If you look at the generated pkg-config file, it will look something like - -``` -libdir=/usr/lib64 -includedir=/usr/include - -Name: gtest -Description: GoogleTest (without main() function) -Version: 1.11.0 -URL: https://github.com/google/googletest -Libs: -L${libdir} -lgtest -lpthread -Cflags: -I${includedir} -DGTEST_HAS_PTHREAD=1 -lpthread -``` - -Notice that the sysroot is not included in `libdir` and `includedir`! If you try -to run `pkg-config` with the correct -`PKG_CONFIG_LIBDIR=/home/MYUSER/sysroot/usr/lib64/pkgconfig` against this `.pc` -file, you will get - -``` -$ pkg-config --cflags gtest --DGTEST_HAS_PTHREAD=1 -lpthread -I/usr/include -$ pkg-config --libs gtest --L/usr/lib64 -lgtest -lpthread -``` - -which is obviously wrong and points to the `CBUILD` and not `CHOST` root. In -order to use this in a cross-compilation setting, we need to tell pkg-config to -inject the actual sysroot into `-I` and `-L` variables. Let us now tell -pkg-config about the actual sysroot - -``` -export PKG_CONFIG_DIR= -export PKG_CONFIG_SYSROOT_DIR=/home/MYUSER/sysroot -export PKG_CONFIG_LIBDIR=${PKG_CONFIG_SYSROOT_DIR}/usr/lib64/pkgconfig -``` - -and running `pkg-config` again we get - -``` -$ pkg-config --cflags gtest --DGTEST_HAS_PTHREAD=1 -lpthread -I/home/MYUSER/sysroot/usr/include -$ pkg-config --libs gtest --L/home/MYUSER/sysroot/usr/lib64 -lgtest -lpthread -``` - -which contains the correct sysroot now. For a more comprehensive guide to also -including `${CHOST}` in build system calls, see the excellent tutorial by Diego -Elio Pettenò: <https://autotools.io/pkgconfig/cross-compiling.html> |