Cmake debug print CMake debugging First, let’s look at ways to debug a CMakeLists or other CMake file. May 6, 2020 · So how is the debug print controlled? find_jar is not listed among supported find_ at CMAKE_FIND_DEBUG_MODE but I seen it was working giving debug output and till output no longer produces after a few runs (few seemingly unrelated code changes) . Everything seems fine in the CMakeLists. You may, however, save a value of the generator expression into the file, but the 378 I use CMake with GNU Make and would like to see all commands exactly (for example how the compiler is executed, all the flags etc. sourceN] [DIRECTORIES dir1 . I'm talking about my variables that I Apr 21, 2022 · Options are meant to be provided from outside not to be modified in the CMake file. I'd like CMake to print out all the paths under which it is searching for LibElf at runtime. Example: cmake_print_variables(CMAKE_C_COMPILER CMAKE_MAJOR_VERSION DOES_NOT_EXIST) Gives: Apr 26, 2020 · Continue to help good content that is interesting, well-researched, and useful, rise to the top! To gain full voting privileges, Mar 22, 2024 · I am compiling a software package and the configuration step of cmake is adding flags to CMAKE_CXX_FLAGS variable that is causing problems when building the software. How to see compile flags and definitions and how to control them. We therefore recommend that you use a debug version of Qt when… Apr 19, 2025 · Relevant source files This document covers how to set compiler flags and control build configurations in CMake projects. Feb 23, 2021 · To make a log level persist between CMake runs, the CMAKE_MESSAGE_LOG_LEVEL variable can be set instead. I followed steps described here under the "This is for MinGW users with Eclipse CDT" h Put cmake find commands in a debug mode when running under calls to find_package(<pkg>), where <pkg> is an entry in the given comma-separated list of case-sensitive package names. Background The […] Sep 18, 2019 · I would like to know if there is any way to debug a cmake process that forcing the command to print mode details about how variables are getting some value. Debugging code # You might need to debug your CMake build, or debug your C++ code. targetN] [SOURCES source1 . Printing variables # The time honored method of print statements looks like this in CMake: Debugging is easy with CMake. I am using cmake to build my project and it seems it breaks when linking. for debugging. GNU make has --debug, but it does not seem to be that helpful are there any other options? Does CMake provide additional flags in the generated Makefile for debugging purpose? LOCATION INTERFACE_INCLUDE_DIRECTORIES) This will print the LOCATION and INTERFACE_INCLUDE_DIRECTORIES properties for both targets foo and bar. Upvoting indicates when questions and answers are useful. Jan 21, 2019 · In its root CMakeLists. Put cmake find commands in a debug mode when running under calls to find_package(<pkg>), where <pkg> is an entry in the given comma-separated list of case-sensitive package names. Enabling this variable is equivalent to using cmake --debug-find with the added ability to enable debugging for a subset of find calls. How to “print-debug” in CMake. If this variable is set and the --log-level command line option is given, the command line option takes precedence. . If you don't have dotty installed, you can still make the target dependencies visible with enabling GLOBAL_DEPENDS_DEBUG_MODE in your CMakeLists. To see the full release notes for this release and what else is included, including bug fixes, please see the release notes. Load this module in CMake with: Aug 9, 2023 · The new CMake Debugger that was introduced in Visual Studio is now available in VS Code. CMakePrintHelpers ¶ Convenience functions for printing properties and variables, useful e. Printing variables The time honored method of print statements looks like this in CMake: May 18, 2025 · Fortunately, CMake provides robust mechanisms to trace, log, and debug the build process, which can help in identifying issues, optimizing performance, and understanding the internal flow of the build system. With that said I don't have experience with android studio. It could be a CMake bug, but I haven't had the time to try a lot of different configurations. ). This can help you verify if the definitions are being applied correctly. Aug 31, 2021 · Learn how to retrieve and display the values of specific CMake variables like CMAKE_CXX_FLAGS_DEBUG and CMAKE_CXX_FLAGS_RELWITHDEBINFO. 15 because of some good new features/improvement in that version. , because otherwise the output will flood you. So is the message type being mapped to VSCode's Output types? but it didn't work for me in 3. my typical invocation with -DCMAKE_VERBOSE_MAKEFILE=ON cmake -GNinja -DCMAKE_VERBOSE_MAKEFILE=ON -Bbuild -H. It explains different methods for setting compile-time definitions, managing compiler options, and specifying build types (Debug, Release, etc. In this video I'll go through your quest Feb 18, 2016 · I could reproduce your problem and you won't get the status messages if CPack's source code is not changed. txt, it attempts to find LibElf via: find_package(LibElf REQUIRED) LibElf doesn't use CMAKE and I haven't configured it to register itself in any way, so of course the find_package fails. I have read in the Qt docs that: The Qt library contains hundreds of internal checks that will print warning messages when a programming error is detected. dirN] [TESTS test1 . In any case you can probably pass some verbose option to Ninja (or make) that prints the compiler invocation commands or Jul 31, 2010 · Can somebody please enlighten me as to what the command line flag to CMake might be that will make it print out all the compile/link commands it executes? I can't find this anywhere in the documentation. entryN] PROPERTIES prop1 . I’m not interested in the CMake variables — as in the --help-variables option. Aug 24, 2015 · You'll need to complete a few actions and gain 15 reputation points before being able to upvote. The -O3 you see is likely set by default in CMAKE_CXX_FLAGS_RELEASE. Dive into the core of the CMake language. Other editors like VS Code will actually show the compiler and let you change it directly in the GUI. 17, the cmake command line has native support for printing the search directories for all of the CMake find_* commands. graph dotty test. Most of the time this works silently, but when something goes wrong, it can be frustrating to figure out what's happening under the hood. Understanding and inspecting the variables used within a CMake project is crucial for debugging and optimization. Note that the command line option takes precedence over the cache variable. I'm not interested in the CMake variables - as in the --help-variables option. txt file for any CMake project in Visual Studio 17. cmake_print_variables (var1 var2 . I use the ${CMAKE_COMMAND} variable (which is set to the absolute path to the invoked cmake executable) with the -E env CTEST_OUTPUT_ON_FAILURE=1 argument to invoke the actual ctest command using ${CMAKE_CTEST_COMMAND} -C $<CONFIG>. How do I tell CMake to output this? May 27, 2025 · Purpose Informational Output The primary function of message () is to display messages during the CMake build process. txt file that contains find_package(Foo), then I can print out the values of variables such as ${Foo_LIBRARIES} and ${Foo_INCLUDES}. txt scripts from VS Code using the CMake Tools Extension. I would like to know what step in cmake process these flags are being added. Printing variables The time honored method of print statements looks like this in CMake: I'm wondering if there is a way to print out all accessible variables in CMake. I looked at running "cmake --debug-output" and then "make -d" but although it showed me tons of information there was nothing about the actual command. Is there an easy way to display these variables without having to run CMake on a CMakeLists. Jul 16, 2018 · How do I print the result of the evaluated generator expression during configuration? You cannot. For single-configuration generators, you can build your code with `-DCMAKE_BUILD_TYPE=Debug` to get debugging flags. varN) This function will print the name of each variable followed by its value. Feb 14, 2017 · CMake messages are only a generation time (when CMake is used to generate your project). e. May 21, 2022 · A little background: I'm writing a game in SFML and I want certain lines of code to be ommitted in Release build. run the command cmake --build --target genexdebug). All other message types are sent to stderr and are not prefixed with hyphens. 15. txt: set_property(GLOBAL PROPERTY GLOBAL_DEPENDS_DEBUG_MODE 1) Feb 15, 2021 · I am trying to enable pretty printing for C++ in Visual Studio Code using MinGW GDB python debugger. Here is a simple way to print them all out. graph See also Generating Dependency Graphs with CMake and CMake Graphviz Output Cleaner. void func () When set, this variable specifies the logging level used by the message () command. Nov 30, 2024 · Sometimes, when working with CMake, it can be helpful to see all the defined variables and their values. We’ll cover two forms of debugging: debugging your CMake code, and debugging your C++ code. Use the --debug-find flag: cmake --debug-find . I want to check during compile time for build type, so that is doesn't impact game's android: Android Studio, CMake. Dec 29, 2020 · I have configured my vscode with CMake the program gives output in the terminal but when debugging there is no output observed. Debug with --debug-output (for debug output) --trace (complete trace) and --trace-expand (trace and expanded variables). I recently upgraded to CMake 3. Both are covered here. For these it is extremely helpful to make progress with point 5. These messages can be used for various purposes: Debugging Print intermediate values, variables, and status updates to help troubleshoot build issues. Question is, I have logs under #ifdef DEBUG which I want to print only for debug build. Mar 3, 2024 · CMake, a powerful cross-platform build system, allows developers to manage the build process of their projects efficiently. How to configure for a debug build or a release build. Is there a cmake CMakePrintHelpers Convenience functions for printing properties and variables, useful e. cmake file? Dec 2, 2023 · Tracing # Trace cmake executable, print the command executed as it runs cmake --trace Aug 12, 2025 · When CMake tries to locate external programs, libraries, or headers, it runs through a detailed search process that can involve system paths, environment variables, CMake cache entries, and custom search directories. In multi-configuration generators, like many IDEs, you can pick the configuration in the IDE. This tutorial explains how to debug 11 My approach is a combination of the answers from ony, from zbyszek, and from tarc. Surprisingly, this often helps to pinpoint the problem. In fact you can't change an option with the option command once it is set in the cache (after the first CMake run). Something like this . The interactive dialogs (ccmake and CMakeSetup) show STATUS messages one at a time on a status line and other messages in interactive pop-up boxes. cmake_print_properties([TARGETS target1 . Is find_jar debug output controlled by CMAKE_FIND_DEBUG_MODE ? In a GCC compiled project, How do I run CMake for each build configuration type (debug/release)? How do I specify debug and release C/C++ flags using CMake? How do I express that the main executable If I run CMake on a CMakeLists. Now, you can debug your CMakeLists. Generator expressions are intended for things, which are not exactly known at configuration stage: they depend on build type, which, in case of multiconfiguration generators, becomes known only at the build stage. 6 Preview 1. The CMake GUI displays all messages in its log area. Aug 26, 2023 · It seems like CMake uses CMAKE_CXX_FLAGS_RELEASE and CMAKE_CXX_FLAGS_DEBUG (depending on the current value of CMAKE_BUILD_TYPE) in addition to CMAKE_CXX_FLAGS. in this case, you must include CMakePrintHelpers Added in version 3. The result I would like Debugging code # You might need to debug your CMake build, or debug your C++ code. Valid values are the same as those for the --log-level command line option of the cmake (1) program. If you look into your CMake generated package makefile rule you will find something like: # Special rule for the target package package: preinstall @$(CMAKE_COMMAND) -E cmake_echo_color --switch=$(COLOR) --cyan "Run Nov 21, 2018 · As of CMake 3. CMakePrintHelpers ¶ This module provides convenience commands, primarily intended for debugging, to print the values of properties and variables. This package has a lot of dependencies, so I am wondering if one of the find package modules in cmake is appending these flags. After I set up CMake Tools I've Aug 16, 2025 · Master CMake build configurations. Apr 16, 2021 · I'm new to cmake, so up front, my apologies this question is too basic . Background The […] Mar 24, 2018 · Enabling Debugging with CMake for a C++ Project tagged C, cmake, Command, configuration, debug, gcc, gdb, How to, Process, root, Tutorial. How to select the compiler. Feb 3, 2023 · Is there a CMake variable that needs to be set in order to enable terminal output in a CMake console app on Windows? Yes, see WIN32 keyword for add_executable () Jun 12, 2015 · cmake --graphviz=test. May 6, 2024 · I’m wondering if there is a way to print out all accessible variables in CMake. How to print debug message in compile time?Thanks for taking the time to learn more. Feb 22, 2023 · We are excited to announce that a preview of the CMake debugger is now available to debug your CMake scripts and CMakeLists. CMake debugging # First, let’s look at ways to debug a CMakeLists or other CMake file. The CMake command-line tool displays STATUS to TRACE messages on stdout with the message preceded by two hyphens and a space. After running cmake, you can then build the genexdebug target to print the result of the $<> expression (i. ¹Well, there are the steveire's CMake Daemon Tools. Could someone suggest where can be a possible mistake? The code runs Jan 18, 2025 · The main advantage of generator expressions in comparison with the old way of CMake is the support of Multi-Config generators where different builds Debug, Release, and so on coexist in the same build directory. Jun 17, 2019 · If you are using cmake KcFNMi's suggestion just needs a bit of tweaking. In my case (using colcon), in addition to changing the log level to debug (via colcon --log-level=debug build), I had to also change the message from STATUS to WARNING before my message appeared. Is there a way to ask cmake to print the cause of rebuild? something like “rebuilding because dependency changed”? I have checked the debug prints, but they are not that useful. txt file, and without having to manually inspect the config. ) which control optimization levels and debugging information. txt so I was wondering if there is any way I can see the exact command that is issued when trying to link. Printing variables # The time honored method of print statements looks like this in CMake: I don't know how CLion runs CMake, but the compiler and other settings are shown in the output during the CMake configure step, which should be done before the build step. Or you could just pass arguments to ninja via cmake during the build step (you would still need to pass -GNinja in your first cmake command) everything after the -- will be passed on to whatever you are using to Nov 8, 2019 · Gotcha. Print extra find call information for the following commands to standard error: find_program() find_library() find_file() find_path() find_package() Output is designed for human consumption and not for parsing. The behavior you're experiencing is how CPack is currently implemented. This lesson explains the difference between single-config (Makefiles) and multi-config (Visual Studio) generators, how to use CMAKE_BUILD_TYPE, and how to write portable, configuration-specific settings with generator expressions. I'm talking about my variables Debugging is easy with CMake. This tutorial shows how to print all available variables in CMake. testN] [CACHE_ENTRIES entry1 . I didn't even try this with cmake directly from the terminal. What's reputation and how do I get it? Instead, you can save this post to reference later. Informative Feedback Provide progress updates, warnings, and general information to the user about the build process Objectives How to get more information. g. propN ) This function prints the values of the properties of the given targets, source files, directories The CMake command-line tool displays STATUS messages on stdout and all other message types on stderr. 15: Added the NOTICE, VERBOSE, DEBUG, and TRACE levels. May 27, 2025 · Print Definitions Use CMake's message () command to print the actual definitions that are being used during the build process. Jan 20, 2022 · 前回はCMake【チュートリアル2】で複数のファイルの扱い方について解説しました しかし、全部手書きしていては手間がかかって仕方ない事も多々あると思います 今回はCMakeで変数・ループ・デバッグの仕方について解説していこうと思います ソースコードはgithubからダウンロ. For example, I see -- Boost version: 1. Jun 26, 2021 · 31 Instead of using message, you can also use cmake_print_variables to display variables. This lesson covers the essentials of CMake syntax, including how to set and reference variables, understand scope, use string interpolation, and print debug messages with the message () command. Aug 9, 2023 · The new CMake Debugger that was introduced in Visual Studio is now available in VS Code. zdnnu splt aswwruje yze icafrj jcqlt plsuq roe pswbmo hrlo ioxzch rarzx ewdu dnsc aagyo