From cb0fd451c2ef6b41b910f82d9d4ca1544cbcae81 Mon Sep 17 00:00:00 2001
From: Mark Ruvald Pedersen <mped@oticon.com>
Date: Wed, 30 Jan 2019 21:48:25 +0100
Subject: [PATCH] cmake: Toolchain abstraction: Assembly

Introduce toolchain_cc_asm macro to capture toolchain specific flags
related to assembly.

-D_ASMLANGUAGE is kept common for all, assuming -D as define flag is
supported by all compilers (which is almost the case).

No functional change expected.

Clang's flags are compatible with gcc, and are thus inherited.

This is motivated by the wish to abstract Zephyr's usage of toolchains,
permitting easier porting to other (commercial) toolchains.

Signed-off-by: Mark Ruvald Pedersen <mped@oticon.com>
---
 CMakeLists.txt                       | 8 +++++++-
 cmake/compiler/clang/target.cmake    | 1 +
 cmake/compiler/gcc/target.cmake      | 1 +
 cmake/compiler/gcc/target_asm.cmake  | 6 ++++++
 cmake/compiler/host-gcc/target.cmake | 1 +
 5 files changed, 16 insertions(+), 1 deletion(-)
 create mode 100644 cmake/compiler/gcc/target_asm.cmake

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4cc238a5190..da0fccb0151 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -205,8 +205,14 @@ zephyr_compile_options(
   ${TOOLCHAIN_C_FLAGS}
 )
 
+# @Intent: Obtain compiler specific flags related to assembly
+toolchain_cc_asm_base_flags(ASM_BASE_FLAG)
+zephyr_compile_options(
+  $<$<COMPILE_LANGUAGE:ASM>:${ASM_BASE_FLAG}>
+)
+
+# Common toolchain-agnostic assembly flags
 zephyr_compile_options(
-  $<$<COMPILE_LANGUAGE:ASM>:-xassembler-with-cpp>
   $<$<COMPILE_LANGUAGE:ASM>:-D_ASMLANGUAGE>
 )
 
diff --git a/cmake/compiler/clang/target.cmake b/cmake/compiler/clang/target.cmake
index fd02fb4539c..4cafe015c52 100644
--- a/cmake/compiler/clang/target.cmake
+++ b/cmake/compiler/clang/target.cmake
@@ -58,3 +58,4 @@ include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_security_fortify.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_security_canaries.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_optimizations.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_cpp.cmake)
+include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_asm.cmake)
diff --git a/cmake/compiler/gcc/target.cmake b/cmake/compiler/gcc/target.cmake
index 037e66a7c55..0db94fbe1c9 100644
--- a/cmake/compiler/gcc/target.cmake
+++ b/cmake/compiler/gcc/target.cmake
@@ -143,3 +143,4 @@ include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_security_fortify.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_security_canaries.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_optimizations.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_cpp.cmake)
+include(${ZEPHYR_BASE}/cmake/compiler/${COMPILER}/target_asm.cmake)
diff --git a/cmake/compiler/gcc/target_asm.cmake b/cmake/compiler/gcc/target_asm.cmake
new file mode 100644
index 00000000000..c942d37b03e
--- /dev/null
+++ b/cmake/compiler/gcc/target_asm.cmake
@@ -0,0 +1,6 @@
+# See root CMakeLists.txt for description and expectations of this macro
+
+macro(toolchain_cc_asm_base_flags dest_var_name)
+  # Specify assembly as the source language for the preprocessor to expect
+  set_ifndef(${dest_var_name} "-xassembler-with-cpp")
+endmacro()
diff --git a/cmake/compiler/host-gcc/target.cmake b/cmake/compiler/host-gcc/target.cmake
index bc318e0e800..004fd5c9692 100644
--- a/cmake/compiler/host-gcc/target.cmake
+++ b/cmake/compiler/host-gcc/target.cmake
@@ -81,3 +81,4 @@ include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_security_fortify.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_security_canaries.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_optimizations.cmake)
 include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_cpp.cmake)
+include(${ZEPHYR_BASE}/cmake/compiler/gcc/target_asm.cmake)