OSDev.org

Hi,
when i compile kernel with these flags
CPPFLAGS = -ffreestanding -nostdlib -fno-builtin -fno-rtti -fno-exceptions -Wal
kernel compiles and runs, but when i want to compile it with CPPFLAGS = -ffreestanding -nostdlib -fno-builtin -fno-rtti -fno-exceptions -fwritable-strings -Wal
everything compiles but kernel doesn't boot.
why?

Because the strings have been moved to the .data section (this is what -fwritable-strings does). So this is affecting your kernel in some way.

i suspect that your bootstrapping asm("jmp kmain") instruction is no longer at the very start of your kernel image or something ...

Just so you know, it should be -Wall, not -Wal (-Wall displays all warnings, -Wal isn't valid)