Re: question regarding bss section

[Ralf Baechle <ralf@linux-mips.org>]

On Mon, Oct 27, 2003 at 09:44:05AM -0800, Teresa Tao wrote:

> I have several questions and hope somebody could help me with the answers:
> 1. how to use gcc to compile the user mode program with larger stack size?

Not at all.  Stack size is a resource limit which is set with can be
manipulated with setrlimit(2) or in bash with the ulimit command.  It
defaults to 8MB.

For pthread applications the stack size is a thead attribute, seem libc
manual.

> 2. Inside the user mode program, I have declared some gloabal data which
> is being put on the bss section and I would like to know whom initialize
> the bss section?

.bss is uninitialized.  Initialized data can't be in .bss.

> How big is the bss section? Under what kind of situation,

As big as needed for everything in it.

> the bss section data could be corrupted?

There's millions of ways of writing broken code.

> 3. What's the difference to compile the program with -G 0 option? That
> menas I don't use the $gp register, will there be any side effect?

-G 0 is the default for userspace.  Iow. passing the option changed nothing.

  Ralf