Warning: attempt to assign the value '8' to the undefined symbol LV_Z_MEM_POOL_NUMBER_BLOCKS when

How-to
1

Description

I upgraded the nrfConnect on VS Code toolchain from 2.5.2 to 2.6.0 and am now getting this error:

warning: attempt to assign the value '8' to the undefined symbol LV_Z_MEM_POOL_NUMBER_BLOCKS

What MCU/Processor/Board and compiler are you using?

I’m using a nRF5340 DK

What LVGL version are you using?

I believe 8.* but I’m not sure how I check from VS Code

When I switch toolchains back to 2.5.2 it compiles and runs fine.

2

I got a reply from Nordic Dev Zone:

It seems the way the LVGL heap is configured is handled a bit differently in the latest version.

In v2.5.2 the heap was scaled based on the LV_Z_MEM_POOL_MAX_SIZE and LV_Z_MEM_POOL_NUMBER_BLOCKS parameters as seen here.

In the later version this was simplified to use just a single parameter, LV_Z_MEM_POOL_SIZE, as seen here.

In other words you should change your project configuration to use this new parameter.

The commit log provides a bit more context:

Best regards
Torbjørn