After building with CMake on Linux (but before installing), all the linked libraries are added to the final executable's RPATH.
However, I would like to prepend $ORIGIN/../lib: to this RPATH.
So far, I've only been able to replace the RPATH, and that's not what I want: I want ld.so to first look in ../lib. This is what I currently do:
set_target_properties(foo PROPERTIES
BUILD_WITH_INSTALL_RPATH TRUE
INSTALL_RPATH "\$ORIGIN/../lib:...")
While this works, it's missing some additional third-party libraries that are not part of my build tree, and who are not located in system directories.
Doing chrpath -l foo gives me the exact same INSTALL_RPATH above. If I don't set those properties, I get the long list of DSO locations, e.g. RPATH=/bar/baz/:/quux/ etc. (the one I'd like to prepend to).
I've tried using get_property(_existing_rpath foo INSTALL_RPATH), but that gives me an empty string
I've read the hints at https://cmake.org/Wiki/CMake_RPATH_handling and noticed under "CMake Bugs" that
At least on CMake 2.6.4 RHEL5, man cmakecommands for
INSTALL_RPATH_USE_LINK_PATH pretends that this setting will append the
link path to any CMAKE_INSTALL_RPATH content one specified. However,
on this version, enabling INSTALL_RPATH_USE_LINK_PATH will replace it.
Well, not so sure about this any more: just verified this on CMake
2.8.0, and now on both versions it does list correct changes in cmake_install.cmake. This bug may have occurred due to previously not
doing per-target install(), or perhaps due to some other changes in
CMake RPATH-related variables.
By the way, I'm only interested in getting a working RPATH for the built files, as in before having run install. I haven't configured the installation properly (added install targets and so on). Do I need to look into that part for this to work?
If you can't find answers on Google, it's often the case that the answer is obvious. This seems to work just fine:
set_target_properties(foo PROPERTIES
BUILD_WITH_INSTALL_RPATH TRUE
INSTALL_RPATH_USE_LINK_PATH TRUE
INSTALL_RPATH "\$ORIGIN/../lib:${INSTALL_RPATH}")
On my system (and CMake 3.6.1), it seems INSTALL_RPATH begins with a colon, but I wouldn't count on it. Also, since I'm obviously setting the global INSTALL_RPATH here, it may be overspecified (I haven't checked).
Related
I'm working on a CMake toolchain file for the new LLVM/Clang based compiler from Texas Instruments (see ARM-CGT-CLANG-1).
CMake properly detects that it's a clang based compiler if I simply set CMAKE_C_COMPILER to the correct path of the tiarmclang binary.
Unfortunately, I've noticed that it does not set CMAKE_AR, CMAKE_NM, CMAKE_READELF and CMAKE_STRIP correctly.
I've went through some of the modules included with CMake, including CMakeDetermineCCompiler and CMakeFindBinUtils.
What I get from that, is that CMakeDetermineCCompiler determines the _CMAKE_TOOLCHAIN_PREFIX using a regular expression which expects a dash (-) in front of clang in the name of the compiler.
This _CMAKE_TOOLCHAIN_PREFIX is later on used in CMakeFindBinUtils to prefix the names of the tools.
Unfortunately, TI decided to not include a dash in the name, which I think is the root cause of CMake not being able to detect the bin utils.
I tried setting the _CMAKE_TOOLCHAIN_PREFIX from the toolchain file, but this does not work (it is overwritten in the CMakeDetermineCCompiler module).
Is there a way to have CMake find the tools automatically, despite the wonky prefix?
Or is setting the variables for each binutil by hand from the toolchain file the only workaround (which I'm doing at the moment)?
After some further investigation, it turns out that setting the correct prefix in the cache will result in the bin utils to be discovered correctly (at least the ones that are included in the TI toolchain):
set(_CMAKE_TOOLCHAIN_PREFIX "tiarm" CACHE INTERNAL "Toolchain prefix" FORCE)
We have a CMakeLists.txt that links (for instance) opencv to our various binaries. This is done as follow:
find_package(OpenCV REQUIRED core imgproc highgui contrib)
target_link_library(XXX opencv_core)
We also would like to allow the person building the library to provide its own opencv library. It seems that this could be done setting -DCMAKE_PREFIX_PATH to the right path.
cmake -DCMAKE_PREFIX_PATH=".../mybuild/include;.../mybuild/lib" .
However I would like to be sure the library used is exactly the one specified by the client (i.e. if there is nothing in /mybuild/lib the configuration fails).
How can I allow somebody building the library to override the library used ? (if nothing is specified it should fall back to find_package-s)
In short
If the package provides <package>Config.cmake script, user may specify <package>_DIR CMake variable for locate this script.
Searching other places in that case may be disabled with NO_DEFAULT_PATH option for find_package().
If a package is searched with Find<package>.cmake script, there is no (generic) way for disable searching other places if user provides hint variable but it is wrong.
Explanations
Firstly, CMAKE_PREFIX_PATH provides additional installation tree for all packages. As this variable is applied to all find_package() calls, it is not wise to require all packages to be found under it.
When talk about the ways for specify installation directory for specific package, we need to distinguish two kinds of "find" scripts:
<package>Config.cmake (or some alternative names, see find_package documentation).
These scripts are shipped with the packages themselves. And there is universal way for user to specify location of such packages: CMake variable <package>_DIR, which should point to the directory with *Config.cmake script.
While default behaviour of find_package() is treating <package>_DIR variable as an additional hint, passing NO_DEFAULT_PATH option disables all implicit paths:
if(<package>_DIR) # Variable is set by the user or by previous `cmake` run.
# Search only under given directory.
find_package(<package> NO_DEFAULT_PATH)
else()
# Search everywhere (as documented for 'find_package').
find_package(<package>)
endif()
Find<package>.cmake.
This script either is shipped with CMake or should be shipped with the project.
Most of such scripts allows to hint about package location with variable (CMake or environment one) like <package>_DIR, <package>_ROOT or so.
However, almost all such scripts treat hint variable only as additional search place, so if variable is set to wrong value, they simply ignore it. And without modifying the script you cannot change that behavior.
I wish to build and install a software locally to the $HOME/.local/ path instead of a system-wide /usr/ folder. The software uses CMAKE for compilation.
After installation, the software binaries and libraries get stored in $HOME/.local/bin/ and $HOME/.local/lib/, respectively. However, when I try to run the program, it throws an error that the required library is not found (which, by the way, is present in $HOME/.local/lib/).
The program works fine if I set the $LD_LIBRARY_PATH to $HOME/.local/lib. But I don't want to do this. Hence, instead of this, I would like to know how to specify the RPATH variable (which would point to $HOME/.local/lib) while compiling the software using CMAKE.
Kindly help.
I am using the following two lines in the CMakefile
set(CMAKE_MACOSX_RPATH 1)
set(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
(the first one is required only if you use MacOSX)
you may also use:
set(CMAKE_BUILD_RPATH "/my/libs/location")
specifying runtime path (RPATH) entries to add to binaries linked in the build tree (for platforms that support it). The entries will not be used for binaries in the install tree. See also the CMAKE_INSTALL_RPATH variable.
CMAKE_INSTALL_RPATH is a predefined list, so I can see scenarios where it would be better to do
list( APPEND CMAKE_INSTALL_RPATH ${CMAKE_INSTALL_PREFIX}/lib )
If you include( GNUInstallDirs ) you could also
list( APPEND CMAKE_INSTALL_RPATH ${CMAKE_INSTALL_LIBDIR} )
I am a CMake novice though, so if someone sees an issue with the above please let me know.
I have a project which builds for PPC, the Toolchain is working correctly, i can build when the sysroot is installed under /opt/poky/1.5. Now i tried to move that Installation to the Project Directory (it is not a part of the Repository there, it is just installed there so it is not reliant on that fix path, so that everyone can check out the project and build it wothout setting up the sysroot under that fixed folder).
To achieve this I set CMAKE_SYSROOT to "${PROJECT_SOURCE_DIR}/poky" where the poky will be installed upon execution of a custom build script (the project also needs to build a secure image, so it is way simpler to use a build script instead of anything else, also this is convenient for jenkins).
Since the CMAKE_SYSROOT is build from the PROJECT_SOURCE_DIR which is different for the CMakeTestCCompiler Project, the cmake call fails teloling me that the CCompiler is broken of course. So I want to know, how I am supposed to get the CMakeTestCCompiler Project to compile with the same CMAKE_SYSROOT variable, without altering the CMakeTestCCompiler Project itself (of course).
Somehow I cannot find an answer anywhere, it seems that noone ever had this issue (which frankly i cannot understand, this should be a common setup in my opinion). (Or maybe i am just too much of a noob when it comes to CMAKE, which i will gladly admit)
I am not interested in solutions like: "JUST INSTALL IT IN A FIX PATH" or such... please, I need the setup like this, I have reasons for that.
THX for reading/trying/answering/helping
Have a nice day
EDIT1:
In CMakeLists.txt (top level CMakeFile so it should be used by any build):
`SET(CMAKE_SYSROOT "${PROJECT_SOURCE_DIR}/poky/sysroots")`
In ToolchainCMake (the one given to the cmake as CMAKE_TOOLCHAIN_FILE):
`SET(CMAKE_SYSTEM_NAME Linux)`
`SET(CMAKE_SYSTEM_VERSION 1)`
`SET(CMAKE_SYSROOT "${PROJECT_SOURCE_DIR}/poky/sysroots")`
`SET(COMPILER_ROOT ${PROJECT_SOURCE_DIR}/poky/sysroots/i686-pokysdk-linux/usr/bin/powerpc-poky-linux-gnuspe)`
`SET(CMAKE_C_COMPILER ${COMPILER_ROOT}/powerpc-poky-linux-gnuspe-gcc)`
`SET(CMAKE_CXX_COMPILER ${COMPILER_ROOT}/powerpc-poky-linux-gnuspe-g++)`
`MESSAGE("CMAKE_C_COMPILER: ${CMAKE_C_COMPILER}")`
`MESSAGE("CMAKE_CXX_COMPILER: ${CMAKE_CXX_COMPILER}")`
`MESSAGE("COMPILER_ROOT: ${COMPILER_ROOT}")`
`SET(CMAKE_FIND_ROOT_PATH ${SYS_ROOT}/ppce500v2-poky-linux-gnuspe)`
`SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)`
`SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)`
`SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)`
EDIT2:
I used the
`set(CMAKE_C_COMPILER_WORKS 1 CACHE INTERNAL "")`
`set(CMAKE_CXX_COMPILER_WORKS 1 CACHE INTERNAL "")`
settings to simulate the CMakeTestCCompiler build succeeding and realized that I am facing some additional problems: It seem that the packages are looked up on the system instead of the CMAKE_SYSROOT folder. Even tried the
`SET(CMAKE_FIND_ROOT_PATH ${CMAKE_SYSROOT})`
to try to force the search in there, but without luck. In the CMakeError.log I can see, that the compiler itself was configured with the prefix option that points to /opt/poky/1.5, the path that i want to "overwrite", now I am not sure if the compiler could even deal with an alternate path.
I felt the need to add these information, they not really add to the problem at hand.
ERRORS:
I also found some errors in the above cmake:
`SET(CMAKE_SYSROOT "${PROJECT_SOURCE_DIR}/poky/sysroots")`
must be
`SET(CMAKE_SYSROOT "${PROJECT_SOURCE_DIR}/poky/sysroots/ppce500v2-poky-linux-gnuspe")`
instead and therefor the
`SET(CMAKE_FIND_ROOT_PATH ${SYS_ROOT}/ppce500v2-poky-linux-gnuspe)`
changes to
`SET(CMAKE_FIND_ROOT_PATH ${CMAKE_SYSROOT})`
EDIT: Whole answer changed.
My first suspicion was that the problem is that value of ${PROJECT_SOURCE_DIR} is not known in CMAKE_TOOLCHAIN_FILE as it is processed before CMakeLists.txt. But this isn't true.
I had similar problem (CMake 2.8.12.2), everything worked OK, when I passed cross compiler by CC environment variable with --sysroot option, i.e. CMake was invoked as follows:
CC="arm-linux-gnueabi-gcc --sysroot=/path/to/sysroot" cmake /path/to/sources
When I switched to using toolchain file, CMake started to report that C compiler doesn't work.
To workaround this problem, I use CMakeForceCompiler package. Parts toolchain file (along with comments) I think are relevant:
include(CMakeForceCompiler)
set(CMAKE_SYSTEM_NAME Linux)
set(CMAKE_SYSTEM_VERSION 1)
# Force compiler - only option that actually works
cmake_force_c_compiler (${TOOLCHAIN_PATH}/bin/arm-linux-gnueabi-gcc GNU)
cmake_force_cxx_compiler(${TOOLCHAIN_PATH}/bin/arm-linux-gnueabi-g++ GNU)
# NOTE: CMAKE_SYSROOT doesn't work as expected
add_definitions("--sysroot=${TOOLCHAIN_SYSROOT}")
set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} --sysroot=${TOOLCHAIN_SYSROOT}" CACHE INTERNAL "" FORCE)
Note, that TOOLCHAIN_PATH and TOOLCHAIN_SYSROOT are my local variables set before.
So, I'm trying to build an application that requires gtkglextmm on CentOS. So far, I grabbed the source (from here) for gtkglext and gtkglextmm, and (finally) figured out how to compile them and install them using ./configure then make then sudo make install. That was pretty cool to get that to work.
Now, I'm trying to build Degate with cmake and it's complaining that it can't find gtkglextmm. What do I need to do to get the gtkglextmm library I built, available for cmake?
Rephrase: Built and installed library a with make,make install. Now want to build application b that depends on a with cmake. How?
Thanks!
This is a newcomer's notes made for my team as we adopt cmake. It summarizes briefly what I thought would be somewhere in a novice's example. Although with references and suitable for novices, I am very new to the material and this example may suffer accordingly.
General info for this question is at: https://cmake.org/Wiki/CMake:How_To_Find_Libraries - in particular, find_package can be used on any of the named packages listed by the help command:
cmake --help-module-list
Note: the 'Find' is omitted (e.g., FindLibXml2 -> find_package(LibXml2) )
However, for this type of library, it is more likely that it will not be in that list, in which case you want to use find_library and find_path instead. A simple example is:
find_library(SQLITE3_LIB sqlite3) # simple because I did not need to give paths
find_path(SQLITE3_PATH sqlite3.h)
target_link_libraries( your_target_name ${SQLITE3_LIB} )
include_directories( ${SQLITE3_PATH} )
You do not need to test if these have the '-NOTFOUND' return value because cmake will exit with an error if they do:
...
CMake Error: The following variables are used in this project, but they are set to NOTFOUND.
Please set them or make sure they are set and tested correctly in the CMake files:
SQLITE3_LIB
linked by target "test" in directory /home/matlab/QFDC_ROOT/api
-- Configuring incomplete, errors occurred!
Note that the all-capitalized 'SQLITE3_LIB' and 'SQLITE3_PATH' are the variable names that I chose. You choose the variable names. If you have other libraries and include directories, you can list them before and after this one and separated by spaces (I ordered them by their link order consistently for both, although I think include paths are insensitive).
Your case may not be so simple, in which case you want to use the CMake features described at find_library for providing CMake more information about where it should find that library. There are other Q&A on specifically that topic - my favorite is to produce your own FindXXX.cmake (although it is a very terse answer pointing you to an example).
In many cases, it is helpful to run make VERBOSE=1 to help you troubleshoot the process, such as cd build && cmake .. && make VERBOSE=1.
For even better diagnostics, I used DLRdave's answer to print out the INCLUDE_DIRS and I used a simple message to return the results of my variables:
message( STATUS "SQLITE3_LIB: ${SQLITE3_LIB} SQLITE3_PATH: ${SQLITE3_PATH}")
get_property(dirs DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR} PROPERTY INCLUDE_DIRECTORIES)
foreach(dir ${dirs})
message(STATUS "dir='${dir}'")
endforeach()
EDIT NOTE: this answer was effectively re-written 2016-04-08 after discovering that the previous day's implementation erred and confused find_library() and find_path().