From 3759d2bc463c92f71285bf6e11c8b7ca756869f5 Mon Sep 17 00:00:00 2001
From: Flatcar Buildbot <buildbot@flatcar-linux.org>
Date: Mon, 3 Jul 2023 07:15:25 +0000
Subject: [PATCH] eclass/cmake: Sync with Gentoo

It's from Gentoo commit b6e2235a3982cad4d74bb7eb49e858835344c3ba.
---
 .../portage-stable/eclass/cmake.eclass        | 29 ++++++++++++-------
 1 file changed, 19 insertions(+), 10 deletions(-)

diff --git a/sdk_container/src/third_party/portage-stable/eclass/cmake.eclass b/sdk_container/src/third_party/portage-stable/eclass/cmake.eclass
index 24787f1c2a..d70f2cbf1f 100644
--- a/sdk_container/src/third_party/portage-stable/eclass/cmake.eclass
+++ b/sdk_container/src/third_party/portage-stable/eclass/cmake.eclass
@@ -293,6 +293,15 @@ _cmake_check_build_dir() {
 		BUILD_DIR="${CMAKE_USE_DIR}"
 	else
 		: "${BUILD_DIR:=${CMAKE_USE_DIR}_build}"
+
+		# Avoid creating ${WORKDIR}_build (which is above WORKDIR).
+		# TODO: For EAPI > 8, we should ban S=WORKDIR for CMake.
+		# See bug #889420.
+		if [[ ${S} == "${WORKDIR}" && ${BUILD_DIR} == "${WORKDIR}_build" ]] ; then
+			eqawarn "QA notice: S=WORKDIR is deprecated for cmake.eclass."
+			eqawarn "Please relocate the sources in src_unpack."
+			BUILD_DIR="${WORKDIR}"/${P}_build
+		fi
 	fi
 
 	einfo "Source directory (CMAKE_USE_DIR): \"${CMAKE_USE_DIR}\""
@@ -484,17 +493,17 @@ cmake_src_configure() {
 		cat >> "${toolchain_file}" <<- _EOF_ || die
 			set(CMAKE_SYSTEM_NAME "${sysname}")
 		_EOF_
+	fi
 
-		if [ "${SYSROOT:-/}" != "/" ] ; then
-			# When cross-compiling with a sysroot (e.g. with crossdev's emerge wrappers)
-			# we need to tell cmake to use libs/headers from the sysroot but programs from / only.
-			cat >> "${toolchain_file}" <<- _EOF_ || die
-				set(CMAKE_SYSROOT "${ESYSROOT}")
-				set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
-				set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
-				set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
-			_EOF_
-		fi
+	if [[ ${SYSROOT:-/} != / ]] ; then
+		# When building with a sysroot (e.g. with crossdev's emerge wrappers)
+		# we need to tell cmake to use libs/headers from the sysroot but programs from / only.
+		cat >> "${toolchain_file}" <<- _EOF_ || die
+			set(CMAKE_SYSROOT "${ESYSROOT}")
+			set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+			set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+			set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
+		_EOF_
 	fi
 
 	if use prefix-guest; then