DEPRECATE: add CMake <3.18 deprecation for April 2026
CMake 3.18 was released on 2020-07-15.
It enables using (and/or dropping workarounds) for these features:
LTO support, better performance and pkg-config support, `OBJECT` target,
`-S`, `-B`, `--verbose`, `--install` on the command-line, lib directory
support in interface targets, target_link_options(), LINK_OPTIONS,
FetchContent, `list(PREPEND ...)`, unity, Ninja, fixed imported global
issues.
Ref: https://github.com/curl/curl/discussions/18704
Closes #19902
diff --git a/docs/DEPRECATE.md b/docs/DEPRECATE.md
index 2a3cbfc..2219bd3 100644
--- a/docs/DEPRECATE.md
+++ b/docs/DEPRECATE.md
@@ -50,6 +50,12 @@
Support for RTMP in libcurl gets removed in April 2026.
+## CMake 3.17 and earlier
+
+We remove support for CMake <3.18 in April 2026.
+
+CMake 3.18 was released on 2020-07-15.
+
## Past removals
- axTLS (removed in 7.63.0)
