Require CMake 3.18 (2020-07-15) or newer, up from 3.7 (2016-11-11)
prior to this patch.
This requirement also applies to the distributed `curl-config.cmake`.
To allow dropping compatibility code maintained for old versions, and to
use features which were unpractical in separate code paths. Also to make
testing, documentation and development easier, CI builds faster due to
CMake performance improvements over time. (e.g. integration tests on
macOS run 8x faster (10 minutes is now under 1.5m) in CI, 2.5x faster on
Windows.)
CMake offers pre-built binaries for major platforms. They work without
an install step, just by unpacking and pointing the cmake command to
them. Making upgrades easy in many cases:
https://cmake.org/download/https://cmake.org/files/https://github.com/Kitware/CMake/releases
CMake 3.18 brings these feature as generally available when building or
consuming curl/libcurl:
LTO support, improved performance, `pkg-config` and interface target
support, `OBJECT` target (for faster libcurl builds), modern invocation
with `-S`/`-B` options, better support for custom linker options,
FetchContent, `GnuTLS::GnuTLS` target, `--verbose` and `--install`
options, `CMAKE_GENERATOR` env, last but not least unity mode and Ninja
generator.
For maximum build speed, use:
`-DCMAKE_UNITY_BUILD=ON -DCURL_DROP_UNUSED=ON`
As for deprecations, C++11 is required to build CMake itself, which may
be a limit on some platforms. autotools continues to cover them.
Follow-up to 9bcdfb3809#20408
Follow-up to a7c974e038#19902
Follow-up to dfbe035c8b#10161
Discussion: https://github.com/curl/curl/discussions/18704Closes#20407
Rework the way curl's custom Find modules advertise their properties.
Before this patch, Find modules returned detected dependency properties
(header dirs, libs, libdirs, C flags, etc.) via global variables. curl's
main `CMakeLists.txt` copied their values into global lists, which it
later applied to targets. This solution worked internally, but it was
unsuited for the public, distributed `CURLConfig.cmake` and publishing
curl's Find modules with it, due to polluting the namespace of consumer
projects. It's also impractical to apply the many individual variables
to every targets depending on libcurl.
To allow using Find modules in consumer projects, this patch makes them
define as imported interface targets, named `CURL::<dependency>`. Then
store dependency information as target properties. It avoids namespace
pollution and makes the dependency information apply automatically
to all targets using `CURL::libcurl_static`.
Find modules continue to return `*_FOUND` and `*_VERSION` variables.
For dependencies detected via `pkg-config`, CMake 3.16+ is recommended.
Older CMake versions have a varying degree of support for
propagating/handling library directories. This may cause issues in envs
where dependencies reside in non-system locations and detected via
`pkg-config` (e.g. macOS + Homebrew). Use `CURL_USE_PKGCONFIG=OFF`
to fix these issues. Or upgrade to newer CMake, or link libcurl
dynamically.
Also:
- re-enable `pkg-config` for old cmake `find_library()` integration
tests.
- make `curlinfo` build after these changes.
- distribute local Find modules.
- export the raw list of lib dependencies via `CURL_LIBRARIES_PRIVATE`.
- `CURLconfig.cmake`: use curl's Find modules to detect dependencies in
the consumer env.
- add custom property to target property debug function.
- the curl build process no longer modifies `CMAKE_C_FLAGS`.
Follow-up to e86542038d#17047
Ref: #14930
Ref: https://github.com/libssh2/libssh2/pull/1535
Ref: https://github.com/libssh2/libssh2/pull/1571
Ref: https://github.com/libssh2/libssh2/pull/1581
Ref: https://github.com/libssh2/libssh2/pull/1623Closes#16973
To not have to guess. Also to sync with autotools, which already uses
this wording.
Also:
- replace the stray term 'folder' with 'directory' for consistency.
- store help text in a temp variable to avoid overly long strings
(mandatory in CMake <4.2.0 and can't be trivially split), also
to avoid repeating this string 4 times.
Ref: https://cmake.org/cmake/help/v4.2/command/set.htmlCloses#19169
It broke cmake builds with OpenSSL 3.5.0 and ngtcp2 1.12.0 or newer,
when detected via `pkg-config`.
For brotli, mbedtls, LDAP, ngtcp2 builds, it caused their version
numbers missing from the configure log when detected via `pkg-config`.
Regression from 01e45f81bd#16980
Regression from 3b501976a9#16479
Bug: https://github.com/curl/curl/pull/16980#issuecomment-2916811388
Reported-by: x-xiang on github
Closes#17476
Apply downstream patch from the vcpkg project:
- cmake/FindBrotli: streamline detecting multiple pkg-config modules.
Add `libbrotlicommon` to `Requires.private` in `libcurl.pc`.
Apply the above idea to the rest of multi-module dependencies:
- cmake/FindMbedTLS: streamline detecting multiple pkg-config modules
Add `mbedx509`, `mbedcrypto` to `Requires.private` in `libcurl.pc`.
- cmake/FindLDAP: streamline detecting multiple pkg-config modules
And sync these changes with autotools, and add `libbrotlicommon`,
`mbedx509`, `mbedcrypto` to `Requires.private`.
Co-authored-by: Kai Pastor
Ref: https://github.com/microsoft/vcpkg/pull/43819Closes#16479
We already avoid system framework paths while looking for LDAP headers
to avoid issues.
Do the same while looking for LDAP libraries. This makes sure to find
the regular ldap library (`libldap.tbd`) instead of picking up
`ldap.framework` and let that seep into `libcurl.pc` with a full path.
This makes LDAP detection work on Apple as before introducing FindLDAP.
Follow-up to 49f2a23d50#15273Closes#15895
Make the Find modules set and return their respective `pkg-config`
module name(s) to the CMake build process, which then adds those
to the `Requires:` list.
Before this patch, `pkg-config` module names were maintainted in two
separate places. After this patch, they are maintained in the Find
modules for dependencies that have one (most do).
Re-align existing modules with this change: msh3, mbedtls, rustls.
These modules return their `pkg-config` module name only when
detected via `pkg-config`.
Follow-up to d511ec8b0a#15573Closes#15800
Move LDAP detection to its own Find module.
It supports `pkg-config` and the standard detection method used for
other dependencies, with version detection.
In curl CI it fixes LDAP detection in the OpenBSD job.
Closes#15273
