mbed-os test build for REALTEK_RTL8195AM,IAR takes ~35 min

[studavekar]

Command used to build

mbed test --compile -m REALTEK_RTL8195AM -t IAR -DMBED_HEAP_STATS_ENABLED=1 -DMBED_STACK_STATS_ENABLED=1 -DMBED_TRAP_ERRORS_ENABLED=1 --clean

Description

• Type: Bug
• Priority: Major

---

Bug

Target
REALTEK_RTL8195AM

Host
Windows

Toolchain:
IAR

mbed-cli version:
(mbed --version)

mbed-os sha:
c60194f Merge pull request #5208 from jeromecoutant/PR_F7_RTC

Expected behavior
Build time should be 2-5 mins

Actual behavior
Build time is around ~35 mins

Steps to reproduce

mbed test --compile -m REALTEK_RTL8195AM -t IAR -DMBED_HEAP_STATS_ENABLED=1 -DMBED_STACK_STATS_ENABLED=1 -DMBED_TRAP_ERRORS_ENABLED=1 --clean

[0xc0170]

cc @tung7970 @Archcady - are you able to reproduce this long-build times?

[Archcady]

IAR elf2bin tool ( aka. ielftool ) is always trying to do zero-padding to the holes of address, which take a long time. Right now we have to cut out useful pieces of binary code from original bin file in post-build process. @0xc0170, any idea to stop ielftool from padding?

[tung7970]

@Archcady rom and image1 should be removed from ICF file for mbed. They are not actually referenced and causing huge zero-padding section.

[0xc0170]

@tung7970 Please send a fix

[tung7970]

After further check, the zero-padding issue is due to multiple separated memory regions. The zero-padding is causing lengthy process time and huge binary size. We were able to solve binary size issue with our post processing script, but not the zero-padding behavior of ielftool.

The reason for having multiple memory regions is to have fine-grain control over object placement. But I think it is not necessary for most cases. Let me check if I can come up with an easy solution.

[tung7970]

@Archcady Please help check if I have broken anything.

[Archcady]

Thanks @tung7970 , It works.

[0xc0170]

This is resolved via a referenced PR above