cmake: Toolchain abstraction: Introducing macro toolchain_cc_imacros

The macro is intended to abstract the -imacros compiler option for
inclusion of the autoconf.h header file. The abstraction allows for a
given toolchain to decide how the inclusion of the header file is to
be done.

The intent here is to abstract Zephyr's dependence on toolchains,
thus allowing for easier porting to other, perhaps commercial,
toolchains and/or usecases.

No functional change expected.

Signed-off-by: Danny Oerndrup <[email protected]>

Author: daor-oti

CMakeLists.txt

@@ -214,12 +214,14 @@ endif()
 # @Intent: Set compiler specific flags for standard C includes
 toolchain_cc_nostdinc()
 
+# @Intent: Set compiler specific macro inclusion of AUTOCONF_H
+toolchain_cc_imacros(${AUTOCONF_H})
+
 # @Intent: Set compiler specific flag for bare metal freestanding option
 toolchain_cc_freestanding()
 
 zephyr_compile_options(
   -g # TODO: build configuration enough?
-  -imacros ${AUTOCONF_H}
   -fno-common
   ${TOOLCHAIN_C_FLAGS}
 )

cmake/compiler/clang/target.cmake

@@ -80,6 +80,7 @@ include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_cpp.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_asm.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_baremetal.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_warnings.cmake)
+include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_imacros.cmake)
 
 macro(toolchain_cc_security_fortify)
   # No op, clang doesn't understand fortify at all

cmake/compiler/gcc/target.cmake

@@ -140,3 +140,4 @@ include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_cpp.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_asm.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_baremetal.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_warnings.cmake)
+include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_imacros.cmake)

cmake/compiler/gcc/target_imacros.cmake

@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: Apache-2.0
+
+# See root CMakeLists.txt for description and expectations of these macros
+
+macro(toolchain_cc_imacros header_file)
+
+  zephyr_compile_options(-imacros ${header_file})
+
+endmacro()

cmake/compiler/host-gcc/target.cmake

@@ -89,3 +89,4 @@ include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_cpp.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_asm.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_baremetal.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_warnings.cmake)
+include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_imacros.cmake)

cmake/compiler/xcc/target.cmake

@@ -83,3 +83,4 @@ include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_cpp.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_asm.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_baremetal.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_warnings.cmake)
+include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_imacros.cmake)