cmake-configure-log(7)¶

Added in version 3.26.

Introduction ¶

CMake writes a running log, known as the configure log, of certain events that occur during the Configure step. The configure log does not contain a log of all output, errors, or messages printed while configuring a project. It is a log of detailed information about specific events, such as toolchain inspection by try_compile(), meant for use in debugging the configuration of a build tree.

For human use, this version of CMake writes the configure log to the file:

${CMAKE_BINARY_DIR}/CMakeFiles/CMakeConfigureLog.yaml

However, the location and name of the log file may change in future versions of CMake. Tools that read the configure log should get its location using a configureLog query to the cmake-file-api(7). See the Log Versioning section below for details.

Log Structure ¶

The configure log is designed to be both machine- and human-readable.

The log file is a YAML document stream containing zero or more YAML documents separated by document markers. Each document begins with a --- document marker line, contains a single YAML mapping that logs events from one CMake "configure" step, and, if the configure step finished normally, ends with a ... document marker line:

---
events:
  -
    kind: "try_compile-v1"
    # (other fields omitted)
  -
    kind: "try_compile-v1"
    # (other fields omitted)
...

A new document is appended to the log every time CMake configures the build tree and logs new events.

The keys of each document root mapping are:

events: A YAML block sequence of nodes corresponding to events logged during one CMake "configure" step. Each event is a YAML node containing one of the Event Kinds documented below.

Log Versioning ¶

Each of the Event Kinds is versioned independently. The set of keys an event's log entry provides is specific to its major version. When an event is logged, the latest version of its event kind that is known to the running version of CMake is always written to the log.

Tools reading the configure log must ignore event kinds and versions they do not understand:

A future version of CMake may introduce a new event kind or version.
If an existing build tree is re-configured with a different version of CMake, the log may contain different versions of the same event kind.
If cmake-file-api(7) queries request one or more configureLog object versions, the log may contain multiple entries for the same event, each with a different version of its event kind.

IDEs should write a cmake-file-api(7) query requesting a specific configureLog object version, before running CMake, and then read the configure log only as described by the file-api reply.

Text Block Encoding ¶

In order to make the log human-readable, text blocks are always represented using YAML literal block scalars (|). Since literal block scalars do not support escaping, backslashes and non-printable characters are encoded at the application layer:

\\ encodes a backslash.
\xXX encodes a byte using two hexadecimal digits, XX.

Event Kinds ¶

Every event kind is represented by a YAML mapping of the form:

kind: "<kind>-v<major>"
backtrace:
  - "<file>:<line> (<function>)"
checks:
  - "Checking for something"
#...event-specific keys...

The keys common to all events are:

kind: A string identifying the event kind and major version.
backtrace: A YAML block sequence reporting the call stack of CMake source locations at which the event occurred, from most-recent to least-recent. Each node is a string specifying one location formatted as <file>:<line> (<function>).
checks: An optional key that is present when the event occurred with at least one pending message(CHECK_START). Its value is a YAML block sequence reporting the stack of pending checks, from most-recent to least-recent. Each node is a string containing a pending check message.

Additional mapping keys are specific to each (versioned) event kind, described below.

Event Kind `message`¶

The message(CONFIGURE_LOG) command logs message events.

There is only one message event major version, version 1.

`message-v1` Event ¶

A message-v1 event is a YAML mapping:

kind: "message-v1"
backtrace:
  - "CMakeLists.txt:123 (message)"
checks:
  - "Checking for something"
message: |
  # ...

The keys specific to message-v1 mappings are:

message: A YAML literal block scalar containing the message text, represented using our Text Block Encoding.

Event Kind `try_compile`¶

The try_compile() command logs try_compile events.

There is only one try_compile event major version, version 1.

`try_compile-v1` Event ¶

A try_compile-v1 event is a YAML mapping:

kind: "try_compile-v1"
backtrace:
  - "CMakeLists.txt:123 (try_compile)"
checks:
  - "Checking for something"
description: "Explicit LOG_DESCRIPTION"
directories:
  source: "/path/to/.../TryCompile-01234"
  binary: "/path/to/.../TryCompile-01234"
cmakeVariables:
  SOME_VARIABLE: "Some Value"
buildResult:
  variable: "COMPILE_RESULT"
  cached: true
  stdout: |
    # ...
  exitCode: 0

The keys specific to try_compile-v1 mappings are:

description

An optional key that is present when the LOG_DESCRIPTION <text> option was used. Its value is a string containing the description <text>.

directories

A mapping describing the directories associated with the compilation attempt. It has the following keys:

source: String specifying the source directory of the try_compile() project.
binary: String specifying the binary directory of the try_compile() project. For non-project invocations, this is often the same as the source directory.

cmakeVariables

An optional key that is present when CMake propagates variables into the test project, either automatically or due to the CMAKE_TRY_COMPILE_PLATFORM_VARIABLES variable. Its value is a mapping from variable names to their values.

buildResult

A mapping describing the result of compiling the test code. It has the following keys:

variable: A string specifying the name of the CMake variable storing the result of trying to build the test project.
cached: A boolean indicating whether the above result variable is stored in the CMake cache.
stdout: A YAML literal block scalar containing the output from building the test project, represented using our Text Block Encoding. This contains build output from both stdout and stderr.
exitCode: An integer specifying the build tool exit code from trying to build the test project.

Event Kind `try_run`¶

The try_run() command logs try_run events.

There is only one try_run event major version, version 1.

`try_run-v1` Event ¶

A try_run-v1 event is a YAML mapping:

kind: "try_run-v1"
backtrace:
  - "CMakeLists.txt:456 (try_run)"
checks:
  - "Checking for something"
description: "Explicit LOG_DESCRIPTION"
directories:
  source: "/path/to/.../TryCompile-56789"
  binary: "/path/to/.../TryCompile-56789"
buildResult:
  variable: "COMPILE_RESULT"
  cached: true
  stdout: |
    # ...
  exitCode: 0
runResult:
  variable: "RUN_RESULT"
  cached: true
  stdout: |
    # ...
  stderr: |
    # ...
  exitCode: 0

The keys specific to try_run-v1 mappings include those documented by the try_compile-v1 event, plus:

runResult

A mapping describing the result of running the test code. It has the following keys:

variable

A string specifying the name of the CMake variable storing the result of trying to run the test executable.

cached

A boolean indicating whether the above result variable is stored in the CMake cache.

stdout

An optional key that is present when the test project built successfully. Its value is a YAML literal block scalar containing output from running the test executable, represented using our Text Block Encoding.

If RUN_OUTPUT_VARIABLE was used, stdout and stderr are captured together, so this will contain both. Otherwise, this will contain only the stdout output.

stderr

An optional key that is present when the test project built successfully and the RUN_OUTPUT_VARIABLE option was not used. Its value is a YAML literal block scalar containing output from running the test executable, represented using our Text Block Encoding.

If RUN_OUTPUT_VARIABLE was used, stdout and stderr are captured together in the stdout key, and this key will not be present. Otherwise, this will contain the stderr output.

exitCode

An optional key that is present when the test project built successfully. Its value is an integer specifying the exit code, or a string containing an error message, from trying to run the test executable.

Event Kind `find`¶

The find_file(), find_path(), find_library(), and find_program() commands log find events.

There is only one find event major version, version 1.

`find-v1` Event ¶

Added in version 4.1.

A find-v1 event is a YAML mapping:

kind: "find-v1"
backtrace:
  - "CMakeLists.txt:456 (find_program)"
mode: "program"
variable: "PROGRAM_PATH"
description: "Docstring for variable"
settings:
  SearchFramework: "NEVER"
  SearchAppBundle: "NEVER"
  CMAKE_FIND_USE_CMAKE_PATH: true
  CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH: true
  CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH: true
  CMAKE_FIND_USE_CMAKE_SYSTEM_PATH: true
  CMAKE_FIND_USE_INSTALL_PREFIX: true
names:
  - "name1"
  - "name2"
candidate_directories:
  - "/path/to/search"
  - "/other/path/to/search"
  - "/path/to/found"
  - "/further/path/to/search"
searched_directories:
  - "/path/to/search"
  - "/other/path/to/search"
found: "/path/to/found/program"

The keys specific to find-v1 mappings are:

mode

A string describing the command using the search performed. One of file, path, program, or library.

variable

The variable to which the search stored its result.

description

The documentation string of the variable.

settings

Search settings active for the search.

SearchFramework: A string describing how framework search is performed. One of FIRST, LAST, ONLY, or NEVER. See CMAKE_FIND_FRAMEWORK.
SearchAppBundle: A string describing how application bundle search is performed. One of FIRST, LAST, ONLY, or NEVER. See CMAKE_FIND_APPBUNDLE.
CMAKE_FIND_USE_CMAKE_PATH: A boolean indicating whether or not CMake-specific cache variables are used when searching. See CMAKE_FIND_USE_CMAKE_PATH.
CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH: A boolean indicating whether or not CMake-specific environment variables are used when searching. See CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH.
CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH: A boolean indicating whether or not platform-specific environment variables are used when searching. See CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH.
CMAKE_FIND_USE_CMAKE_SYSTEM_PATH: A boolean indicating whether or not platform-specific CMake variables are used when searching. See CMAKE_FIND_USE_CMAKE_SYSTEM_PATH.
CMAKE_FIND_USE_INSTALL_PREFIX: A boolean indicating whether or not the install prefix is used when searching. See CMAKE_FIND_USE_INSTALL_PREFIX.

names

The names to look for the queries.

candidate_directories

Candidate directories, in order, to look in during the search.

searched_directories

Directories, in order, looked at during the search process.

found

Either a string representing the found value or false if it was not found.

search_context

A mapping of variable names to search paths specified by them (either a string or an array of strings depending on the variable). Environment variables are wrapped with ENV{ and }, otherwise CMake variables are used. Only variables with any paths specified are used.

package_stack

An array of objects with paths which come from the stack of paths made available by find_package() calls.

package_paths: The paths made available by find_package() commands in the call stack.

Event Kind `find_package`¶

Added in version 4.1.

The find_package() command logs find_package events.

There is only one find_package event major version, version 1.

`find_package-v1` Event ¶

A find_package-v1 event is a YAML mapping:

kind: "find_package-v1"
backtrace:
  - "CMakeLists.txt:456 (find_program)"
name: "PackageName"
components:
  -
    name: "Component"
    required: true
    found: true
configs:
  -
    filename: PackageNameConfig.cmake
    kind: "cmake"
  -
    filename: packagename-config.cmake
    kind: "cmake"
version_request:
  version: "1.0"
  version_complete: "1.0...1.5"
  min: "INCLUDE"
  max: "INCLUDE"
  exact: false
settings:
  required: "optional"
  quiet: false
  global: false
  policy_scope: true
  bypass_provider: false
  hints:
    - "/hint/path"
  names:
    - "name1"
    - "name2"
  search_paths:
    - "/search/path"
  path_suffixes:
    - ""
    - "suffix"
  registry_view: "HOST"
  paths:
    CMAKE_FIND_USE_CMAKE_PATH: true
    CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH: true
    CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH: true
    CMAKE_FIND_USE_CMAKE_SYSTEM_PATH: true
    CMAKE_FIND_USE_INSTALL_PREFIX: true
    CMAKE_FIND_USE_PACKAGE_ROOT_PATH: true
    CMAKE_FIND_USE_CMAKE_PACKAGE_REGISTRY: true
    CMAKE_FIND_USE_SYSTEM_PACKAGE_REGISTRY: true
    CMAKE_FIND_ROOT_PATH_MODE: "BOTH"
  candidates:
    -
      path: "/path/to/config/PackageName/PackageNameConfig.cmake"
      mode: "config"
      reason: "insufficient_version"
    -
      path: "/path/to/config/PackageName/packagename-config.cmake"
      mode: "config"
      reason: "no_exist"
  found:
    path: "/path/to/config/PackageName-2.5/PackageNameConfig.cmake"
    mode: "config"
    version: "2.5"

The keys specific to find_package-v1 mappings are:

name

The name of the requested package.

components

If present, an array of objects containing the fields:

name: The name of the component.
required: A boolean indicating whether the component is required or optional.
found: A boolean indicating whether the component was found or not.

configs

If present, an array of objects indicating the configuration files to search for.

filename: The filename of the configuration file.
kind: The kind of file. Either cmake or cps.

version_request

An object indicating the version constraints on the search.

version: The minimum version required.
version_complete: The user-provided version range.
min: Whether to INCLUDE or EXCLUDE the lower bound on the version range.
max: Whether to INCLUDE or EXCLUDE the upper bound on the version range.
exact: A boolean indicating whether an EXACT version match was requested.

settings

Search settings active for the search.

required

The requirement request of the search. One of optional, optional_explicit, required_explicit, required_from_package_variable, or required_from_find_variable.

quiet

A boolean indicating whether the search is QUIET or not.

global

A boolean indicating whether the GLOBAL keyword has been provided or not.

policy_scope

A boolean indicating whether the NO_POLICY_SCOPE keyword has been provided or not.

bypass_provider

A boolean indicating whether the BYPASS_PROVIDER keyword has been provided or not.

hints

An array of paths provided as HINTS.

names

An array of package names to use when searching, provided by NAMES.

search_paths

An array of paths to search, provided by PATHS.

path_suffixes

An array of suffixes to use when searching, provided by PATH_SUFFIXES.

registry_view

The REGISTRY_VIEW requested for the search.

paths

Path settings active for the search.

CMAKE_FIND_USE_CMAKE_PATH: A boolean indicating whether or not CMake-specific cache variables are used when searching. See CMAKE_FIND_USE_CMAKE_PATH.
CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH: A boolean indicating whether or not CMake-specific environment variables are used when searching. See CMAKE_FIND_USE_CMAKE_ENVIRONMENT_PATH.
CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH: A boolean indicating whether or not platform-specific environment variables are used when searching. See CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH.
CMAKE_FIND_USE_CMAKE_SYSTEM_PATH: A boolean indicating whether or not platform-specific CMake variables are used when searching. See CMAKE_FIND_USE_CMAKE_SYSTEM_PATH.
CMAKE_FIND_USE_INSTALL_PREFIX: A boolean indicating whether or not the install prefix is used when searching. See CMAKE_FIND_USE_INSTALL_PREFIX.
CMAKE_FIND_USE_CMAKE_PACKAGE_REGISTRY: A boolean indicating whether or not to search the CMake package registry for the package. See CMAKE_FIND_USE_PACKAGE_REGISTRY.
CMAKE_FIND_USE_SYSTEM_PACKAGE_REGISTRY: A boolean indicating whether or not to search the system CMake package registry for the package. See CMAKE_FIND_USE_SYSTEM_PACKAGE_REGISTRY.
CMAKE_FIND_ROOT_PATH_MODE: A string indicating the root path mode in effect as selected by the CMAKE_FIND_ROOT_PATH_BOTH, ONLY_CMAKE_FIND_ROOT_PATH, and NO_CMAKE_FIND_ROOT_PATH arguments.

candidates

An array of rejected candidate paths. Each element contains the following keys:

path: The path to the considered file. In the case of a dependency provider, the value is in the form of dependency_provider::<COMMAND_NAME>.
mode: The mode which found the file. One of module, cps, cmake, or provider.
reason: The reason the path was rejected. One of insufficient_version, no_exist, ignored, no_config_file, or not_found.
message: If present, a string describing why the package is considered as not found.