CMake: Command line too long on Ninja/ARMClang on Windows

[ccli8]

Description of defect

On Ninja/ARMClang, Win10, mbed-os-example-for-azure is failed to compile. The cause seems to related to the bugfix below:

mbed-os/CMakeLists.txt

Lines 245 to 252 in c734138

	# Ninja requires to be forced for response files
	if ("${CMAKE_GENERATOR}" MATCHES "Ninja")
	# known issue ARMClang and Ninja with response files for windows
	# https://gitlab.kitware.com/cmake/cmake/-/issues/21093
	if(NOT (CMAKE_HOST_SYSTEM_NAME MATCHES "Windows" AND CMAKE_CXX_COMPILER_ID MATCHES "ARMClang"))
	set(CMAKE_NINJA_FORCE_RESPONSE_FILE 1 CACHE INTERNAL "")
	endif()
	endif()

However, after the bugfix, a new issue is introduced: command line too long.

Target(s) affected by this defect ?

DISCO_L475VG_IOT01A

Toolchain(s) (name and version) displaying this defect ?

ARM Compiler 6.12

What version of Mbed-os are you using (tag or sha) ?

mbed-os-6.9.0

What version(s) of tools are you using. List all that apply (E.g. mbed-cli)

mbed-tools: 7.8.0
CMake: 3.19.3
Ninja:: 1.10.2

How is this defect reproduced ?

1. Clone mbed-os-example-for-azure and navigate to mbed-os-6.9.0 tag.

   git clone https://github.com/ARMmbed/mbed-os-example-for-azure
   mbed update -C mbed-os-6.9.0

2. No need to change azure cloud related setting. Just focus on compile process.

3. Patch CMakeLists.txt to be compatible with mbed-tools 7.8.0

    set(MBED_CONFIG_PATH ${CMAKE_CURRENT_BINARY_DIR} CACHE INTERNAL "")
    ......
    mbed_set_mbed_target_linker_script(${APP_TARGET})
    

4. Build on Ninja/ARMClang

   mbed-tools configure -m DISCO_L475VG_IOT01A -t ARM
   cmake -S . -B cmake_build/DISCO_L475VG_IOT01A/develop/ARM -GNinja -DCMAKE_BUILD_TYPE=develop
   cmake --build cmake_build/DISCO_L475VG_IOT01A/develop/ARM
   

5. Error log with command line stripped

   CreateProcess failed. Command attempted:
   "C:\Keil_v5\ARM\ARMCLANG\bin\armclang.exe --target=arm-arm-none-eabi -DARM_MATH_CM4 ......
   ninja: fatal: CreateProcess: The parameter is incorrect.    
   (is the command line too long?)
   

[0xc0170]

We can't use response files for ARMClang on windows due to the bug there 😢
This is unfortunate and we might need to look at fixing CMake issue (it's still opened as I can see).

[ciarmcom]

Thank you for raising this detailed GitHub issue. I am now notifying our internal issue triagers.
Internal Jira reference: https://jira.arm.com/browse/IOTOSM-3813

[0xc0170]

Adding the CMake issue here https://gitlab.kitware.com/cmake/cmake/-/issues/21093

[0xc0170]

The pull request https://gitlab.kitware.com/cmake/cmake/-/merge_requests/6484 was merged, It will be part of the next release.

We can remove the workaround once its fixed. meanwhile, feel free to use their release candidate.