[OE-core] Larger kernel with gcc-6.2 than gcc-5.x

[Bryan Evenson]

All,

I'm on poky/krogoth and I am in the process of moving to poky/morty on an Atmel AT91SAM9G25 platform (arm926ejste architecture).  On the first try booting with my image built under morty, I noticed that the kernel image was larger.  I've done some more testing and I see that the rest of the image is the same size, just the kernel got larger.  I'm using a custom kernel, so the kernel image is using the same commit, patches and configuration.

I decided to try building with both gcc-6.2 and gcc-5.4 and see what the size differences were.  My results:
Kernel size under poky/morty with gcc-6.2: 3158616 bytes
Kernel size under poky/morty with gcc-5.4: 3141312 bytes
Kernel size under poky/krogoth with gcc-5.3: 3144200 bytes

It's not a huge change and I have the space for the larger kernel.  However, I was curious if this was a sign that something else changed that I should be concerned about.  Has anyone else seen gcc-6.2 producing larger binaries?  If so, does anyone know why?

Thanks,
Bryan