We need to ramp up detection of unsupported CMake build systems with
CMake 4. This will detect CMakeLists.txt files setting insufficient cmake_minimum_required VERSION level even in project subdirectories,
putting out appropriate eqawarn message about the need to fix ${PN}.

That makes us not rely on tinderbox runs w/ unmasked cmake-4 slowly
being able to build everything up to leaf packages, and also helps
detect insufficient subproject minimums that could otherwise be masked
by USE flag choice.

Bug: https://bugs.gentoo.org/951350
Signed-off-by: Andreas Sturmlechner <asturm@gentoo.org>
---
eclass/cmake.eclass | 20 +++++++++++++++++++-
1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/eclass/cmake.eclass b/eclass/cmake.eclass
index 083b566d26..8a3f2db7c4 100644
--- a/eclass/cmake.eclass
+++ b/eclass/cmake.eclass
@@ -243,6 +243,25 @@ _cmake_modify-cmakelists() {
# Only edit the files once
grep -qs "<<< Gentoo configuration >>>" "${CMAKE_USE_DIR}"/CMakeLists.txt && return 0

+ local x re="VERSION( .*\.\.\.| )(([[:digit:]]+)\.([[:digit:]]+))"
+ local ver isold
+ for x in $(find "${CMAKE_USE_DIR}" -type f -iname "CMakeLists.txt" -exec \
+ grep -li "cmake_minimum_required\s*(.*)" {} \;); do
+
+ [[ $(grep -hi "cmake_minimum_required" $x) =~ $re ]]
+ ver="${BASH_REMATCH[2]}"
+
+ if ver_test $ver -lt "3.5"; then
+ isold=true
+ fi
+ done
+ if [[ ${isold} ]]; then
+ eqawarn "QA Notice: Compatibility with CMake < 3.5 has been removed from CMake 4,"
+ eqawarn "${CATEGORY}/${PN} will fail to build w/o a fix."
+ eqawarn "See also tracker bug #951350;