Bug in flash_placement.xml example file?

Question

I am using nRF5 SDK version 17.1.0 and am seeing this line in file examples/ble_peripheral/ble_app_uart/pca10040/s132/ses/flash_placement.xml 
 <ProgramSection alignment="4" load="Yes" name=".text" size="0x4" /> 
 Why is the size of this section specified as only 0x4? 
 I find it hard to believe that a program would have only a 4-byte section named ".text".... 
 Cheers 
 RVM

Vidar Berg · Accepted Answer

Hi Ramanand, 
 We were not been able to find any documentation for this behavior in the Segger documentation now, but through earlier testing and validation we confirmed that the section sometimes did not get aligned without the .size argument. It's not clear whether this is the intended behavior or not, we would have to reach out to Segger to confirm this. 
 Cheers 
 Vidar 
 Edit: correction, the alignment argument does work. .align=4 makes it so that the sections always start at a word aligned address. The problem fixed by .size=4 was that size was also aligned to a four byte boundary as shown below: 
 left side has .size=4 
 
 2 byte *fill* to make size word aligned: 
 
 This ensures that empty spaces in the app image are always filled with the same values (either 0xff or 0x00). Previously we would sometimes see a discrepancy when programming the *.elf file instead of the *.hex file due to different padding rules, which is problematic when you try to compute a CRC of the image for Boot validation .

Bug in flash_placement.xml example file?

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