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
Backtrack on previous change that aimed to solve the wrong `share.h`
being included. It turns out it did not fix this issue. At the same time
it introduced relative header filenames and the need to include the same
headers differently depending on the source files' location, reducing
readability and editability.
Replace this method by re-adding curl's lib source directory to the
header path and addressing headers by the their full, relative name to
that base directory. Aligning with this method already used in src and
tests.
With these advantages:
- makes includes easier to read, recognize, grep, sort, write, and copy
between sources,
- syncs the way these headers are included across curl components,
- avoids the ambiguity between system `schannel.h`, `rustls.h` vs.
local headers using the same names in `lib/vtls`,
- silences clang-tidy `readability-duplicate-include` checker, which
detects the above issue,
Ref: https://clang.llvm.org/extra/clang-tidy/checks/readability/duplicate-include.html
- possibly silences TIOBE coding standard warnings:
`6.10.2.a: Don't use relative paths in #include statements.`
- long shot: it works well with concatenated test sources, for
clang-tidy-friendly custom unity builds. Ref: #20667
Slight downside: it's not enforced.
If there happens to be a collision between a local `lib/*.h` header and
a system one, the solution is to rename (possibly with its `.c`
counterpart) into the `curl_` namespace. This is also the method used by
curl in the past.
Also:
- curlx/inet_pton: reduce scope of an include.
- toolx/tool_time: apply this to an include, and update VS project
files accordingly. Also dropping unnecessary lib/curlx header path.
- clang-tidy: enable `readability-duplicate-include`.
Follow-up to 3887069c66#19676
Follow-up to 625f2c1644#16991#16949Closes#20623
Instead of globally disabling unity for all targets when clang-tidy is
enabled.
After this patch `CMAKE_UNITY_BUILD=ON` is honored for:
- static libcurl when building both static and shared separately.
- libcurlu and libcurltool internal libraries when building the test
target.
While keeping unity disabled for the libcurl build pass running
clang-tidy, and the curl tool, also running clang-tidy.
To make clang-tidy-enabled builds finish faster when unity mode is
enabled, yet performs the same clang-tidy checks as before this patch.
Effect on:
- GHA/macos: core build: same, buils tests 5-12 seconds faster,
with steps going down from 259 to 25.
52s: https://github.com/curl/curl/actions/runs/22279958340/job/64448913325 ->
47s: https://github.com/curl/curl/actions/runs/22279873606/job/64448710743
- GHA/windows (not enabled): it'd save about 1 minute, bringing total
time barely below 10m, still one of the slowest jobs overall.
(#20667 is trying a way for 4x speed-up (with a drawback)).
5m21s: https://github.com/curl/curl/actions/runs/22222907068/job/64284556852 ->
4m26s: https://github.com/curl/curl/actions/runs/22281033369/job/64451601548Closes#20670
On platforms that require building static and shared libcurl separately,
after this change clang-tidy is only run on one of them, to reduce build
time by avoiding the double-work. From a clang-tidy standpoint, static
and shared libs are identical.
Except `dllmain.c` on Windows, which is only present in shared. To keep
running it through clang-tidy, prefer the shared library for clang-tidy.
Closes#20675
To enable known linker options dropping unused, dead, code and data from
the executables built.
Useful to reduce binary sizes for curl, libcurl shared lib and apps
linking static libcurl. It's effective on both "unity" and non-unity
builds. Aligning "unity" build sizes with default, non-unity ones.
Supported platforms: Apple, MSVC, llvm/clang and GCC on all tested
platforms: Linux, BSDs, Windows, MSYS2/Cygwin, Android, MS-DOS.
Notes:
- Static libraries grow 20-30% with non-Apple toolchains.
This effect is controlled by separate, optional compiler flags on
non-Apple. This patch enables them automatically for public binaries
(libcurl and curl tool), and leaves them off for internal/test ones.
- MSVC enables this option by default for 'Release' configurations.
The curl build option has no effect on it.
- Observed effect on VS2010 is negligible. VS2012+ is recommended.
- Works with LTO, Fil-C.
- No observed/conclusive effect on build speed.
- On Windows with clang/gcc (mingw-w64/MSYS2/Cygwin) it also enables
`-fno-asynchronous-unwind-tables` as a workaround to make
the toolchain options actually work.
Ref: https://sourceware.org/bugzilla/show_bug.cgi?id=11539
Thanks-to: Andarwinux
Also:
- GHA: enable in Linux and MinGW jobs to test it. Size changes:
- linux aws-lc H3:
curl: 2000000 -> 1937152, libcurl.a: 2065724 -> 2716532 bytes
- macos clang HTTP-only:
curl: 1364376 -> 128799 bytes, libcurl.a: unchanged
- macos llvm MultiSSL:
curl: 410056 -> 405720, libcurl.dylib: 1350336 -> 1348480 bytes
- mingw schannel c-ares U:
curl: 1588736 -> 1507328, libcurl-d.a: 3322040 -> 3884746 bytes
bld: 34 -> 35MB
- GHA: enable in MSVC and Apple jobs to reduce disk footprint, with no
obvious downside. Size changes:
- AppVeyor CI VS2019:
curl: 2339840 -> 1295872, libcurl-d.dll: 3155968 -> 1900544 bytes
bld: 161 -> 97MB
- AppVeyor CI VS2022 clang-cl:
curl: 2933248 -> 2332160, libcurl-d.lib: 4762688 -> 5511330 bytes
bld: 133 -> 121MB
- AppVeyor CI VS2022 HTTP-only:
curl: 3514368 -> 2177024, libcurl-d.lib: 2538420 -> 3151740 bytes
bld: 137 -> 83MB
- GHA intel:
curl: 2629120 -> 2023424, libcurl-d.lib: 4366652 -> 5350670 bytes
bld: 86 -> 69MB
- GHA arm64:
curl: 2832896 -> 2063872, libcurl-d.lib: 4690616 -> 5597250 bytes
bld: 82 -> 66MB
Refs:
https://maskray.me/blog/2021-02-28-linker-garbage-collectionhttps://web.archive.org/web/20110811230637/msdn.microsoft.com/en-us/library/bxwfs976.aspx (VS2010)
https://learn.microsoft.com/cpp/build/reference/opt-optimizationshttps://learn.microsoft.com/cpp/build/reference/gy-enable-function-level-linkingCloses#20357
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
Based on existing code and commit history it appears
`CURL_DISABLE_INSTALL` means to prevent calling `install()`;
`CURL_ENABLE_EXPORT_TARGET` means to prevent calling `export()` and
`install()`s with `EXPORT` in them.
Fix them to also apply to the lib and src directories in that vain:
- lib: honor `CURL_DISABLE_INSTALL`
- src: honor `CURL_DISABLE_INSTALL`
- src: honor `CURL_ENABLE_EXPORT_TARGET`
https://cmake.org/cmake/help/v4.2/command/install.htmlhttps://cmake.org/cmake/help/v4.2/command/export.html
- `CURL_DISABLE_INSTALL` follow-up to:
aace27b096#12287
- `CURL_ENABLE_EXPORT_TARGET` follow-up to:
8698825106#9638643ec29645#7060Closes#19144
- tests: merge cmake commands.
- tests: use `target_compile_definitions()`.
- tests/server: use generator expression for platform-specific macro.
- tests/unit: sync `Makefile.am` comment with cmake.
- tests/unit: merge two `AM_CPPFLAGS` lines to keep synced with cmake.
- tests: move macro definitions to `first.h` headers from build level.
`CURL_NO_OLDIES`, `CURL_DISABLE_DEPRECATION`, `WITHOUT_LIBCURL`,
`CURL_STATICLIB` (for servers).
To share more logic.
Pass `CURL_STATICLIB` in server on all platforms for simplicity.
(On non-Windows, it's a no-op. It's already done like this with curlu
and libcurltool.)
Also for lib:
- lib: merge commands.
- lib: sync macro order with tests (also in `Makefile.am`).
Closes#17768
In order to do unit tests for private functions, functions that are
marked UNITTEST but without a global scope in the library, functions
that do not have prototypes in their corresponding header file, unit
tests previously brought their own private prototype *copy* into the
unit test.
This was error-prone when the internal function changes but the change
might be missed in the unit test which then uses an outdated prototype
copy for testing.
This change removes the private prototypes from unit tests and instead
introduces a C file parser that parses the specific C files and extracts
the necessary unit test prototypes into a generated header file for unit
tests to use. This geneated lib/unitprotos.h header is then included by
unit tests that need private prototypes.
Assisted-by: Viktor Szakats
Closes#17750
The c-ares header directory was added to the header path within `lib`,
as opposed to every other dependency which added them in the root
`CMakeLists.txt`. Such exception is no longer necessary. This patch
aligns c-ares header setup with the rest of dependencies. And also with
autotools, which also makes no exception here.
Cherry-picked from #17705
Cherry-picked from #16973Closes#17707
- cmake: use `CURL_RCFILES` instead of literal.
- cmake: use `LIB_RCFILES` instead of literal.
- cmake: fix comments.
- autotools: use `CURL_RCFILES` in `EXTRA_DIST`.
- autotools: use `LIB_RCFILES` in `EXTRA_DIST`.
- autotools: fix comments.
- autotools: fix indentation.
Closes#17694
To pass `-municode` to the linker. Before this patch we passed this via
`target_link_libraries()` which is designed to pass libraries. Keep
using it for old CMake versions, where no better alternative existed.
https://cmake.org/cmake/help/latest/command/target_link_options.html
Also:
- also pass `-municode` as `PRIVATE` for old cmake versions.
(it should not make a difference because no target depends on the curl
tool, but this seem to be the modern, non-ambiguous syntax.)
- unfold a bunch of split lines for greppability of `add_library()` and
`add_executable()` commands.
- quote a string.
Closes#17670
Before this patch `memdebug.c` was compiled as a separate source in
unity builds. This was necessary because `memdebug.c` failed to compile
if `memdebug.h` was included before it, in `CURLDEBUG` mode. This patch
fixes this issue and allows to compile `memdebug.c` as part of the unity
source batch. This removes an exception and makes builds perform a notch
better.
- introduce `CURL_SCLOSE()` macro as an immutable synonym of `sclose()`.
- memdebug: replace `sclose()` reference with `CURL_SCLOSE()` to compile
as expected when `sclose()` is overridden by `memdebug.h`.
- memdebug: make it not break when including `memdebug.h` before it in
`CURLDEBUG` mode. Do this by calling low-level functions as
`(function)`.
- autotools, cmake: drop memdebug exception, include it like any other
source file. This is now possible because `memdebug.c` doesn't break
if `memdebug.h` was included before it, in `CURLDEBUG` builds.
- mk-unity: drop `--exclude` option. No longer used after this patch.
- drop `MEMDEBUG_NODEFINES` macro hack. No longer necessary.
Ref: #16747Closes#16746Closes#16738Closes#17631
Make test bundles the default. Drop non-bundle build mode.
Also do all the optimizations and tidy-ups this allows, simpler builds,
less bundle exceptions, streamlined build mechanics.
Also rework the init/deinit macro magic for unit tests. The new method
allows using unique init/deinit function names, and calling them with
arguments. This is in turn makes it possible to reduce the use of global
variables.
Note this drop existing build options `-DCURL_TEST_BUNDLES=` from cmake
and `--enable-test-bundles` / `--disable-test-bundles` from autotools.
Also:
- rename test entry functions to have unique names: `test_<testname>`
This removes the last exception that was handled in the generator.
- fix `make dist` to not miss test sources with test bundles enabled.
- sync and merge `tests/mk-bundle.pl` into `scripts/mk-unity.pl`.
- mk-unity.pl: add `--embed` option and use it when `CURL_CLANG_TIDY=ON`
to ensure that `clang-tidy` does not miss external test C sources.
(because `clang-tidy` ignores code that's #included.)
- tests/unit: drop no-op setup/stop functions.
- tests: reduce symbol scopes, global macros, other fixes and tidy-ups.
- tool1621: fix to run, also fix it to pass.
- sockfilt: fix Windows compiler warning in certain unity include order,
by explicitly including `warnless.h`.
Follow-up to 6897aeb105#17468Closes#17590
These libraries do not support TLS 1.3 and have been marked for removal
for over a year. We want to help users select a TLS dependency that is
future-proof and reliable, and not supporting TLS 1.3 in 2025 does not
infer confidence. Users who build libcurl are likely to be served better
and get something more future-proof with a TLS library that supports
1.3.
Closes#16677
Move curlx_ functions into its own subdir.
The idea is to use the curlx_ prefix proper on these functions, and use
these same function names both in tool, lib and test suite source code.
Stop the previous special #define setup for curlx_ names.
The printf defines are now done for the library alone. Tests no longer
use the printf defines. The tool code sets its own defines. The printf
functions are not curlx, they are publicly available.
The strcase defines are not curlx_ functions and should not be used by
tool or server code.
dynbuf, warnless, base64, strparse, timeval, timediff are now proper
curlx functions.
When libcurl is built statically, the functions from the library can be
used as-is. The key is then that the functions must work as-is, without
having to be recompiled for use in tool/tests. This avoids symbol
collisions - when libcurl is built statically, we use those functions
directly when building the tool/tests. When libcurl is shared, we
build/link them separately for the tool/tests.
Assisted-by: Jay Satiro
Closes#17253
To avoid having LTO enabled for Debug configurations with multi-config
generators (e.g. MSVC.)
Reported-by: PleaseJustDont
Fixes#17042
Ref: ##17034
Follow-up to a1eaa12a83#15829Closes#17043
- `NOT` + `VERSION_LESS` -> `VERSION_GREATER_EQUAL`
Available since 3.7, which is the minimum required for curl:
https://cmake.org/cmake/help/latest/command/if.html#version-greater-equal
- make `CMAKE_REQUIRED_*` argument quotes consistent.
- make `CMAKE_REQUIRED_*` space alignment consistent.
- drop quote from version value for consistency with other cases.
- formatting
Closes#17002
by including headers using "../[header]" when done from C files in
subdirectories, we do not need to specify the lib source dir as an
include path and we reduce the risk of header name collisions with
headers in the SDK using the same file names.
Idea-by: Kai Pastor
Ref: #16949Closes#16991
Also adjust `()` around low-level calls preventing macro overrides via
e.g. `memdebug.h`:
- add for `malloc` and `free`.
- drop for `_open`. (We do not override `_open` in curl.)
Tidy-up: also sync libcurlu custom macro order in cmake with autotools.
Follow-up to f42a279ee3#11928Closes#16742
It seems unnecessary and possibly unexpected to build test servers with
debug-enabled features and memory tracking whenever the tested curl is
built like that (which is a requirement for some tests, so curl is
mostly built like that when running tests.) It also makes building
servers a little bit faster with cmake for the most common cases.
You can apply debug options to `tests/server` with these new options:
- `./configure`: `--enable-server-debug`.
- cmake: `-DENABLE_SERVER_DEBUG`.
Also sync the way we pass these macros in autotools, with CMake builds.
Before this patch, autotools passed them via `curl_config.h`. After this
patch it passes them on the command-line, like cmake builds do.
This patch also make these option no longer passed to examples and
`http/client` in cmake builds, where they were no-ops anyway.
Ref: #15000Closes#16705
Sync it with cmake to:
- exclude it from all builds except Windows and Cygwin.
- exclude it from unity builds for Cygwin to avoid the included
`windows.h` header interfere with the rest of the code.
Also:
- fix to trim ending spaces from `CSOURCES` for the `tidy` target.
The solution requires a non-POSIX `-E` `sed` option. Supported by BSD
and GNU implementations.
Follow-up to 37523c91bc#16480
Follow-up to 60c3d04465#14815
Follow-up to 7860f575fe#12408Closes#16712
Apply downstream patches from the vcpkg project:
- cmake: remove duplicates from `CURL_LIBDIRS`.
- cmake: set `CURL_LIBDIRS` as `INTERFACE_LINK_DIRECTORIES` for static
libcurl.
To support CMake <3.13, change downstream patch from:
```cmake
target_link_directories(${LIB_STATIC} INTERFACE ${CURL_LIBDIRS})
```
to:
```cmake
set_target_properties(${LIB_STATIC} PROPERTIES [...] INTERFACE_LINK_DIRECTORIES "${CURL_LIBDIRS}")
```
Co-authored-by: Kai Pastor
Ref: https://github.com/microsoft/vcpkg/pull/43819Closes#16610
- replace `add_compile_options()`, `add_definitions()` with directory
properties. To harmonize this across all scripts. The new commands are
verbose, but describe better how they work. The syntax is also closer
to setting target properties, helps grepping.
- prefer `CMAKE_INSTALL_PREFIX` over `--prefix` (in tests, CI).
- tidy up cmake invocations.
- formatting.
Closes#16238
Allow overriding the `IMPORT_LIB_SUFFIX` default with an empty value.
Also:
- add a fatal error if the implib and static lib filename are identical.
- clarify `IMPORT_LIB_SUFFIX` default value in the documentation.
Reported-by: RubisetCie on Github
Fixes#16324
Ref: 1199308dbc#11505Closes#16332
Default curl unity builds make a single unit for each target. It means
all target sources are batched together and built in a single compiler
invocation. With multi-core CPUs this doesn't always result in the best
possible performance. This patch enables smaller batches for jobs where
this resulted in shorter build times. These jobs are Cygwin, MSYS2,
MinGW, running on the Windows runners.
Use batch of 30 (meaning 30 sources batched into units), and 32 for
Cygwin/MSYS2 to avoid a unity fallout that's subject to a different PR.
(CMake allows to set the number of sources per unit, not the number
of units, though the latter may be more practical to max out CPU cores.)
Also override to not batch the `curlu` target because batching lost
a little bit of time there, due to the already existing parallelism when
building the `testdeps` targets.
For jobs on the macOS and Linux runners jobs were already mostly single
digit or below teen seconds, and batching didn't improve on them
noticeably. On VM jobs, the virtual CPUs are limited, so I didn't
make a try. In AppVeyor and GHA vcpkg jobs (using msbuild), batching
didn't result in conclusive or any gains.
Build times in seconds (curl + testdeps):
Job | Before | After w curlu=0 | Gain
:--------------------| :-------------- | :-------------- | :---
cygwin, CM | 19 + 32 = 51 | 12 + 32 = 44 | 7
msys2, CM | 7 + 15 = 22 | 5 + 14 = 19 | 3
mingw gcc U, CM | 19 + 30 = 49 | 13 + 32 = 45 | 4
mingw ucrt, CM | 32 + 42 = 74 | 15 + 43 = 58 | 16
mingw clang, CM | 15 + 21 = 36 | 8 + 21 = 29 | 7
mingw uwp, CM | 30 + 40 = 70 | 14 + 40 = 54 | 16
mingw gcc, CM | 20 + 31 = 51 | 12 + 31 = 43 | 8
mingw x86, CM | 35 + 40 = 75 | 15 + 38 = 53 | 22
dl-mingw, CM 9.5.0 | 88 + 99 = 187 | 42 + 101 = 143 | 44
dl-mingw, CM 7.3.0 U | 24 + 32 = 56 | 17 + 35 = 52 | 4
Total | | | 131
Total gain per GHA/windows workflow runs: 2m11s
Runs:
Before: https://github.com/curl/curl/actions/runs/13220256084/job/36904342259
After: https://github.com/curl/curl/actions/runs/13220383702/job/36904602981https://github.com/curl/curl/actions/runs/13220613141/job/36905170104https://github.com/curl/curl/actions/runs/13222019443/job/36908358550
With curlu tweak: https://github.com/curl/curl/actions/runs/13222239255/job/36908782462
Ref: 116950a250#16265Closes#16272
Before this patch `CURL_LTO` only applied to builds explicitly
configured for `Release` or `RelWithDebInfo` via `CURL_BUILD_TYPE`.
After this patch it enables LTO regardess of build type.
Also:
- GHA/linux: enable LTO in an existing job.
Follow-up to 4ccf7622db#4799Closes#15829
Prefix (or suffix) curl-defined macro and function names with `curl`.
To avoid collisions with non-curl CMake and to make them recognizable
as curl-specific calls.
Closes#15498
When compiled with BUILD_STATIC_LIBS=ON and SHARE_LIB_OBJECT=OFF compile
definition CURL_STATICLIB was not set for static library. It seems to be
copy-paste error in the lib/CMakeLists.txt.
This pull request fixes it.
Closes#15695
`BUILD_TESTING` variable is used by other projects and CMake internally.
Replace `cmake_dependent_option()` with `option()` and introduce an
internal variable to track if want and can do testing.
Follow-up to #6036
Follow-up to 3a1e798009#6072
Reported-by: Robert Maynard
Fixes#15351Closes#15355
