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Hi @all,
I´m writing my kernel in FreeBASIC. Now I´m at the point where I should use interrupts. So I wrote some functions that create and load a IDT. I wrote a function and created an IDT-entry for it. Then I tried to call int 0 to test it, but instead of printing text to the screen, the kernel crashed.
I hope you can help me, I have no ideas what to do.

The version of my kernel with the problem is here: http://darkinsanity.freehoster.ch/FROST_debug.zip

The logfile of Bochs is here: http://darkinsanity.freehoster.ch/bochs.log

I bet you loaded the wrong address into the idtr. Whats the code that actually loads it?

Try adding a break point in Bochs at the instruction where you invoke the error, then running 'info itd' in the debugger.
Then add restart and add a break point for the required error handler then run again. If the handler is called step through it until it errors itself.

I think that the fault is caused by calling 'IRET' from within a function's stack frame, normally you would use an assembler stub that saves the registers and then calls the C/BASIC handler.

I looked at your code and I bet it crashes because the idt is loaded wrong. put a breakpoint right after the lidt instruction, then type info idt 0x00 and see what laddr of that entry is

Ouchouchouch

No stack configured
Broken ISR stubs (mixing assembly with freebasic prologue/epilogue)
General language abuse (WTF is code doing in HEADER files)

the horror

Combuster wrote:(WTF is code doing in HEADER files)

This reminds me of good ol' Pascal

ok, the problem is solved. it was because the structure of the IDT-entries were automaticaly aligned on the 4-byte boundaries.
and i´ll fix that broken isr stubs soon ^^
thx for your help