Comparing big array in Segger embedded studio in release mode cause the issue

[iqcosmicxx]

I see two different issue from Segger ES. The below piece of code work well in debug mode, comparison of array at 2k and it fails at release mode.
Wondering what's happening?

//2kb
static uint8_t m_buffer_tx[2048];
static uint8_t m_buffer_rx[2048];

 //this always fails in Segger ES release mode but becomes true in Debug mode.
 if (memcmp(m_buffer_tx, m_buffer_rx, 2048) == 0) {
     NRF_LOG_INFO("Data consistent"); 
 }

if I change the buffer size compariosn to 512 I can see memcmpr passes. I am using Arm coterx-M4 its 32bit. I presume 2kb is not much of stack that i am comapring?

[awneil]

So look at the differences between your release mode, and debug mode.

What debugging have you done?

Have you checked that the buffers are actually consistent?

ie, how do you know that the problem is in the comparison, and not in the buffer contents?

Do you have some asynchronous task(s) writing to these buffers ?

[iqcosmicxx]

I try to print the buffer using NRF_LOG_HXDUMP_INFO() for 2048 but the logs are dropped. I compared the 512 bytes they are identical. I guess its something with the Segger ES release doing some aggressive optimization. Thanks for your answer.

[Vidar Berg]

You can inspect the array while you debug the application in SES:

1. right click on the array and select Add <variable name> to watch. The "Watch" view should pop up on right side after this.

2. Right click on the watched variable and select how many elements you want to view (2048)

Are you doing anything to these arrays apart from initializing them? 

[awneil]

Are you sure that the logs are enabled in your RELEASE build ?