[poky] [PATCH 05/25] u-boot: disable -Os option not supported by gcc

[Wolfgang Denk]

Dear Darren Hart,

In message <4D3884A0.8030602 at linux.intel.com> you wrote:
>
> I ran into this in the recent u-boot_git.bb recipe I added. Rather than 
> create a patch to the Makefile, I found it simpler to adding OPTFLAGS to 
> the EXTRA_OEMAKE variable in the recipe:
> 
> EXTRA_OEMAKE = "CROSS_COMPILE=${TARGET_PREFIX} OPTFLAGS=''"
> 
> This negates the -Os in the Makefile.

What exactly is the reason that -Os is not supported?


Note that -Os makes is intentional in U-Boot, and omitting it may
cause problems on a number of systems.

-O2 will create significantly larger code which does not fit into
flash sectors on some systems; on other systems, the code will not
fit any more in the size limitations given by the NAND loader.

In other works, -O2 breaks a number of systems.

I discourage doing this.

Best regards,

Wolfgang Denk

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