From c34bbe5fa9024655180c5949515e457ca0e74c78 Mon Sep 17 00:00:00 2001
From: Khem Raj <raj.khem@gmail.com>
Date: Mon, 28 Apr 2025 14:26:16 -0700
Subject: [PATCH] cmake.bbclass: Enhance to emit a native toolchain cmake file

Some components e.g. clang and its runtime needs the native toolchain
defines especially when doing nativesdk builds it uses
CROSS_TOOLCHAIN_FLAGS_NATIVE to pass native toolchain file, which is
then used to build native llvm tools needed during nativesdk builds

Moreover this would enable using OE built native toolchain e.g.
clang-native to build cmake based packages. e.g. libcxx and other llvm
runtime plus it can be used for build native packages which require clang

(From OE-Core rev: 79dc6a23234a34403157dec10d0cdd839ca76b3e)

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
---
 meta/classes-recipe/cmake.bbclass | 58 +++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/meta/classes-recipe/cmake.bbclass b/meta/classes-recipe/cmake.bbclass
index b342deb671..449fe2bb44 100644
--- a/meta/classes-recipe/cmake.bbclass
+++ b/meta/classes-recipe/cmake.bbclass
@@ -50,11 +50,34 @@ OECMAKE_C_COMPILER_LAUNCHER ?= "${@oecmake_map_compiler('CC', d)[1]}"
 OECMAKE_CXX_COMPILER ?= "${@oecmake_map_compiler('CXX', d)[0]}"
 OECMAKE_CXX_COMPILER_LAUNCHER ?= "${@oecmake_map_compiler('CXX', d)[1]}"
 
+# Native C/C++ Compiler (without cpu arch/tune arguments)
+OECMAKE_NATIVE_C_COMPILER ?= "${@oecmake_map_compiler('BUILD_CC', d)[0]}"
+OECMAKE_NATIVE_C_COMPILER_LAUNCHER ?= "${@oecmake_map_compiler('BUILD_CC', d)[1]}"
+OECMAKE_NATIVE_CXX_COMPILER ?= "${@oecmake_map_compiler('BUILD_CXX', d)[0]}"
+OECMAKE_NATIVE_CXX_COMPILER_LAUNCHER ?= "${@oecmake_map_compiler('BUILD_CXX', d)[1]}"
+OECMAKE_NATIVE_AR ?= "${BUILD_AR}"
+OECMAKE_NATIVE_RANLIB ?= "${BUILD_RANLIB}"
+OECMAKE_NATIVE_NM ?= "${BUILD_NM}"
+
+# Native compiler flags
+OECMAKE_NATIVE_C_FLAGS ?= "${BUILD_CC_ARCH} ${BUILD_CFLAGS}"
+OECMAKE_NATIVE_CXX_FLAGS ?= "${BUILD_CC_ARCH} ${BUILD_CXXFLAGS}"
+OECMAKE_NATIVE_C_FLAGS_RELEASE ?= "-DNDEBUG"
+OECMAKE_NATIVE_CXX_FLAGS_RELEASE ?= "-DNDEBUG"
+OECMAKE_NATIVE_C_LINK_FLAGS ?= "${BUILD_CC_ARCH} ${BUILD_CPPFLAGS} ${BUILD_LDFLAGS}"
+OECMAKE_NATIVE_CXX_LINK_FLAGS ?= "${BUILD_CC_ARCH} ${BUILD_CXXFLAGS} ${BUILD_LDFLAGS}"
+BUILD_CXXFLAGS += "${BUILD_CC_ARCH}"
+BUILD_CFLAGS += "${BUILD_CC_ARCH}"
+
 # clear compiler vars for allarch to avoid sig hash difference
 OECMAKE_C_COMPILER:allarch = ""
 OECMAKE_C_COMPILER_LAUNCHER:allarch = ""
 OECMAKE_CXX_COMPILER:allarch = ""
 OECMAKE_CXX_COMPILER_LAUNCHER:allarch = ""
+OECMAKE_NATIVE_C_COMPILER:allarch = ""
+OECMAKE_NATIVE_C_COMPILER_LAUNCHER:allarch = ""
+OECMAKE_NATIVE_CXX_COMPILER:allarch = ""
+OECMAKE_NATIVE_CXX_COMPILER_LAUNCHER:allarch = ""
 
 OECMAKE_RPATH ?= ""
 OECMAKE_PERLNATIVE_DIR ??= ""
@@ -155,6 +178,41 @@ set( CMAKE_LIBRARY_PATH ${libdir} ${base_libdir})
 list(APPEND CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES ${includedir})
 list(APPEND CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES ${includedir})
 
+EOF
+        cat > ${WORKDIR}/toolchain-native.cmake <<EOF
+set( CMAKE_SYSTEM_NAME ${@map_host_os_to_system_name(d.getVar('BUILD_OS'))} )
+set( CMAKE_SYSTEM_PROCESSOR ${@map_host_arch_to_uname_arch(d.getVar('BUILD_ARCH'))} )
+set( CMAKE_C_COMPILER ${OECMAKE_NATIVE_C_COMPILER} )
+set( CMAKE_CXX_COMPILER ${OECMAKE_NATIVE_CXX_COMPILER} )
+set( CMAKE_ASM_COMPILER ${OECMAKE_NATIVE_C_COMPILER} )
+set( CMAKE_AR ${OECMAKE_NATIVE_AR} CACHE FILEPATH "Archiver" )
+set( CMAKE_RANLIB ${OECMAKE_NATIVE_RANLIB} CACHE FILEPATH "Archive Indexer" )
+set( CMAKE_NM ${OECMAKE_NATIVE_NM} CACHE FILEPATH "Symbol Lister" )
+set( CMAKE_C_FLAGS "${OECMAKE_NATIVE_C_FLAGS}" CACHE STRING "CFLAGS" )
+set( CMAKE_CXX_FLAGS "${OECMAKE_NATIVE_CXX_FLAGS}" CACHE STRING "CXXFLAGS" )
+set( CMAKE_ASM_FLAGS "${OECMAKE_NATIVE_C_FLAGS}" CACHE STRING "ASM FLAGS" )
+set( CMAKE_C_FLAGS_RELEASE "${OECMAKE_NATIVE_C_FLAGS_RELEASE}" CACHE STRING "Additional CFLAGS for release" )
+set( CMAKE_CXX_FLAGS_RELEASE "${OECMAKE_NATIVE_CXX_FLAGS_RELEASE}" CACHE STRING "Additional CXXFLAGS for release" )
+set( CMAKE_ASM_FLAGS_RELEASE "${OECMAKE_NATIVE_C_FLAGS_RELEASE}" CACHE STRING "Additional ASM FLAGS for release" )
+set( CMAKE_C_LINK_FLAGS "${OECMAKE_NATIVE_C_LINK_FLAGS}" CACHE STRING "LDFLAGS" )
+set( CMAKE_CXX_LINK_FLAGS "${OECMAKE_NATIVE_CXX_LINK_FLAGS}" CACHE STRING "LDFLAGS" )
+
+set( CMAKE_FIND_ROOT_PATH ${STAGING_DIR_NATIVE} )
+set( CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY )
+set( CMAKE_FIND_ROOT_PATH_MODE_PROGRAM BOTH )
+set( CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY )
+set( CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY )
+
+# Use native cmake modules
+list(APPEND CMAKE_MODULE_PATH "${STAGING_DATADIR_NATIVE}/cmake/Modules/")
+
+# add for non /usr/lib libdir, e.g. /usr/lib64
+set( CMAKE_LIBRARY_PATH ${STAGING_BASE_LIBDIR_NATIVE} ${STAGING_LIBDIR_NATIVE})
+
+# add include dir to implicit includes in case it differs from /usr/include
+list(APPEND CMAKE_C_IMPLICIT_INCLUDE_DIRECTORIES ${STAGING_INCDIR_NATIVE})
+list(APPEND CMAKE_CXX_IMPLICIT_INCLUDE_DIRECTORIES ${STAGING_INCDIR_NATIVE})
+
 EOF
 }