Support configuring stack size in RTOS-less build

[ccli8]

Description

• Type: Enhancement
• Priority: Major

mbed-os sha:
mbed-os-5.8.3

I am evaluating Mbed Cloud 1.3.1 on NUMAKER_PFM_M487/GCC_ARM. In mbed-bootloader, it is built with RTOS disabled. With stack size hard-coded to 0x800 in linker script file, I meet stack overflow on printf() call. For RTOS enabled, I can change main thread's stack size through mbed_app.json (MBED_CONF_APP_MAIN_STACK_SIZE). But for RTOS disabled, it seems there's no way except modifying linker script file.

[0xc0170]

@SenRamakri @bulislaw Please review
[Mirrored to Jira]

[bulislaw]

Hi @ccli8 you are right it doesn't make sense to have 2k stack and huge heap. We should be able to configure it with some sane default. We'll try to have a look into that soonish.
[Mirrored to Jira]

[andrewleech]

On an barely related note, is there an official easy to build without RTOS?
Is .mbedignore the rtos folder it, or is there a better way?
[Mirrored to Jira]

[bulislaw]

Right now we don't support it officially. We acknowledge it's a legitimate use case so we try not to break it, but we don't actively maintain it. We may revisit that for next major release.
[Mirrored to Jira]

[ccli8]

Any update?

Besides, same as rtos-less main stack size, it is also needed to make rtos kernel stack size configurable. I meet stack overrun with them in Mbed Cloud.
[Mirrored to Jira]

[0xc0170]

@ccli8 Isn't this trying to address this issue : #7238 ?
[Mirrored to Jira]

[ccli8]

@0xc0170 Yes, #7238 is addressing the issue.
[Mirrored to Jira]

[adbridge]

Internal Jira reference: https://jira.arm.com/browse/IOTCORE-261

[ccli8]

Done with #8039