GCC Segment issue

[pranjas]

Hi,

While coding my IDT and GDT descriptor tables which were declared to be global i found out something very strange.

I have a structure named ExceptionGate so i declared 48 of them like this,

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struct ExceptionGate interrupts[48]={0};

GCC does gives a warning but this is

supposedly initialized data

correct?

However when i looked at the objdump of sections of the object file i found out this array was going into the bss section which already housed my stack and things went really ugly guys! Spent almost 3 days figuring out what i did wrong!

Finally i appeneded section attribute like this,

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struct ExceptionGate interrupts[48] __attribute__((section(".data")))={0};

which did worked indeed.

So the question is do i've to this everytime i declare a global variable? Anyone else who has done similar thing to get data into correct segments?

These are my CFLAGS for make

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CFLAGS = -c -nostartfiles -nostdlib -nodefaultlibs -fno-builtin -Wall -ffreestanding -fno-common

and CPPFLAGS as

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CPPFLAGS= -c -nostartfiles -nostdlib -nodefaultlibs -fno-builtin -Wall -ffreestanding -fno-rtti -fno-exceptions -nostdinc++ -fno-common

I'm using

gcc (SUSE Linux) 4.4.1 [gcc-4_4-branch revision 150839]