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naand's avatar
naand
Icon for New Contributor rankNew Contributor
1 year ago

NIOS II - FW doesn't work with compiler optimization turned on

Dear support team, I have a problem with the behavior of the firmware if the project is built in release mode with optimization enabled. The problem occurs during the write-to-flash routine. I u...
Nios Cpu
wwanalim_intel's avatar
wwanalim_intel
Icon for Contributor rankContributor
1 year ago

Hi,

Since project cannot be shared, then we will suggest ways for you to debug the issue.

We recommend for you to enable a single optimization until the design fails. Once you can find the optimization that cause the issue then can remove it and proceed without using it for your design.

Since -O3 is using bunch of optimizations, we should try one by one:

-O0 (working or not)

-O1 (work with which optimization)

-O2 (work with O1 and plus which optimization)

-O3 (failing because of which optimization)

Based on the closer working/failing pair, we will have a smaller group to investigate.

For example,

If the pair is found to be O2-O3, these are the interested optimization to investigate

https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html


Thank you.

Regards,

Fathulnaim


naand's avatar
naand
Icon for New Contributor rankNew Contributor
1 year ago

Hi,

I tried as you suggested.

With optimization O1 the firmware works properly, whereas the firmware doesn't work with optimization O2, so the pair is O1-O2.

To investigate further, is it possible to disable only one optimization flag of O2 and find out which flag generates the issue?

And is it possible to turn off optimization for a block of code?

Thank you.

Regards,

naand