I am looking for a way for CMake to query which version of the linker is currently being used. I have to fail a build if the linker version is too high or low. So far I could not find an easy way to do so except to execute the command ld --version and parse the output manually which is ugly and won't work cross-platform.
Thanks!
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I'm a *nix user, installing LLVM is easy for me, just download the precompiled file, set LLVM_DIR, and you're done. But I'm having a lot of problems with Windows ...
I downloaded LLVM-<version>-win64.exe from the GitHub release, but I can't find LLVMConfig.cmake file. Then I tried to compile LLVM from the source following this documentation.
When I started compiling my own project, I got this error:
'C:/<...>/Debug/libLLVMSupport.lib', needed by '<...>.exe', missing and no known rule to make it
I guess maybe I'm missing some compile options. but I can't find the documentation for LLVM_ENABLE_PROJECTS or BUILD_SHARED_LIBS, not even a list of component names.
I tried to add -DBUILD_SHARED_LIBS=ON but CMake told me BUILD_SHARED_LIBS option is not supported on Windows.
The good news, I was able to compile and install Clang and lld from branch llvmorg-12.0.1 under Windows / Cygwin.
It compiles my code fine but linker says:
lld: error: unknown argument: --dll-search-prefix=cyg
I am wondering because of I thought lld takes the same cli parameters as ld.
I am working on a project which includes gtest and uses the cmake framework. The files for testing are linked as library and later again the tests and finally again gtest.
The code is linking and working when using ggc 11.2.0
--dll-search-prefix is a win32-specific option of ld which is not (yet) implemented in lld.
I would like to use CMake and clang-tidy in my project, however I see that build times are quite a bit higher when I use this in all the main cmake file:
set(CMAKE_CXX_CLANG_TIDY
clang-tidy-11;
-format-style='file';
-header-filter=${CMAKE_CURRENT_SOURCE_DIR};
)
It is working well, but I don't want to have this build-time penalty every time I build the project during development. Therefore I thought I would make a separate target that builds all, but uses clang-tidy. And when I do a regular debug or release build it does not do any checking. However I don't know how to do this in Cmake. Do I make a custom target with a command "cmake --build" with a target_set_property of CMAKE_CXX_CLANG_TIDY?
This feels rather clunky, so my question is, are there other ways to do this?
however I see that build times are quite a bit higher when I use this in all the main cmake file:
You're going to have to pay for the cost of running clang-tidy sometime or another. It's essentially running the first few phases of a compiler to analyze your code and look for errors.
Setting CMAKE_CXX_CLANG_TIDY runs clang-tidy in line with your build, as you have observed.
This feels rather clunky, so my question is, are there other ways to do this?
Yes. When using the Ninja or Makefile generators, you may set -DCMAKE_EXPORT_COMPILE_COMMANDS=ON at the command line. That will create a file called compile_commands.json in your build folder that the standalone clang-tidy can read.
In sum, at the command line, you would manually run:
$ cmake -G Ninja -S . -B build -DCMAKE_EXPORT_COMPILE_COMMANDS=ON
$ clang-tidy-11 -format-style=file -header-filter=. -p build
The -p flag tells clang-tidy in which directory to find your compile_commands.json.
I'm trying to get cmake working on msys2. I try to compile some code that I've been given for another project and:
CMake Error: Could not create named generator MSYS Makefiles
I've found this thread and this thread and tried to follow the instructions...only to realize that the wiki that the threads eventually link back to never states where msys stores toolchains. Googling around didn't really help.
Even more oddly, the program that I'm trying to use somehow runs and produces valid data despite throwing an error due to the missing cmake. I don't get it.
I've never used msys before; as someone who's brand new to msys2/cygwin and can't even understand the lingo, how do I get cmake installed and working?
Sounds like you are specifying a -G "MSYS Makefiles" as the CMake generator, but CMake doesn't recognize that generator. When I use CMake on msys2 I just use the default Unix Makefiles generator and everything works just fine. Also, on my current msys2 install, CMake doesn't seem to have a MSYS Makefile generator that I can see (running cmake --help will list the available generators). Try running cmake without the -G option. Also, make sure make is installed first via pacman -Sy make.
I'm trying to use CppUTest in Windows, first step is to get it to work and I already have problems. These are the things I've tried:
First Approach
With CMake, using the cmake GUI I can do the configure and generate command and I get something in the output directory, but no binaries and no libraries, just a bunch of cmakefiles. The CMake GUI says everything went OK during the configuration and generation steps, however the libraries (.lib files) are not generated in the output directory... is there something I am missing? I've never used CMake before.
Second approach
With MinGW and msys alone, running cmd in Windows and executing a MinGW shell by typing sh in the Windows terminal, afterwards I execute the following commands:
cd <CppUTest folder>
mount c:\mingw /mingw
./autogen.sh
./configure
make
The build process starts but it fails with a message indicating that pthread.h was not found in MinGW directory. If I install the pthread-win32 package with the MinGW package manager and repeat the same steps as above the build process starts but fails with a message indicating that the structure timespec is defined in time.h and pthread.h.
I've tried to follow this same procedure with CppUTest 3.6 and it works perfectly fine, I get the .lib files, so I guess I will have to continue with this for now.
Does anyone know how to build CppUTest 3.7 (latest release) with MinGW or CMake?
In the end I used Cygwin to compile it, I couldn't find a way to compile it with MinGW properly, I added a dirty trick to make it compile under MinGW (handled the timespec redifinition) but chances are that is going to cause issues.
Just make sure that you use Cygwin aswell to compile your tests, something that I found out after making this question (https://www.youtube.com/watch?v=oVmd0P85D8o).