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You can just eliminate the align line if you don't plan using paging / mapping kernel sections as RO, etc. If you delete it it wont be faster, the kernel will be smaller (in size).spiner900 wrote:If i dontuse it i can use a différent number and more that number is smal better is the memory speed.
ELF in a kernel is only useful if you are using a bootloader which supports it (ie: GRUB) or when you want your OS to load applications, in which you can compile them as ELF and load them.When I said ELF is the same as PE I would say if ELF is a executable as PE and not if ELF is 100% like PE. And if I was under Window, canI use ELF to build my kernel ?
Or you could take the normal elf32 and use objcopy. And if I remember correctly, COFF is a relocatable object format and not a finished excecutable format.gzaloprgm wrote:Yes, you can try compiling as a 32 bit COFF and then using a tool such as objdump to convert it to a plain binary file.
Smaller isn't better, more aligned is better. Accessing a multibyte variable is faster on boundaries evenly divisible by the size of the value. So 32-bit variables should be aligned to 4 bytes, 64-bit to 8 bytes, 128-bit to 16, etc. I said 16 because thats typically the biggest data size you will see.If i dontuse it i can use a différent number and more that number is smal better is the memory speed.
I really don't see what's wrong with letting LD do the conversion to a flat binary for you. Something like the following should work fine, and I find it just as easy (if not easier, since it requires less steps) than using objcopy.JohnnyTheDon wrote:Or you could take the normal elf32 and use objcopy. And if I remember correctly, COFF is a relocatable object format and not a finished excecutable format.gzaloprgm wrote:Yes, you can try compiling as a 32 bit COFF and then using a tool such as objdump to convert it to a plain binary file.
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ld --oformat binary -Ttext 0x0 -o kernel.bin kernel.o startup.o ...Much easier to load by a custom bootloaderneon wrote:Only question I have is why one would want a plain binary kernel anyways. I do not see any benefit of it.
True. Easier is not always better though.Much easier to load by a custom bootloader