Bryce,
Your ld script seems messed up. You have your stack starting at the
same location as your heap. The heap starts at _end and moves up. The
stack starts at _stack and moves down. In your ld script you have your
stack preceding your heap. You should be placing your stack high above
your heap as they will both eat into this storage. Your low-level sbrk
function should check for collision.
If you issue an arm-elf-ld with the --verbose option and no files, you
can see the default ld script which you can use as a basis for writing
your own if you like. You should use this as a basis for your script.
I have attached the default script for a really old arm-elf build I have
lying around.
Note how the stack starts up high at 0x80000.
-- Jeff J.
Bryce Schober wrote:
Ping.
Bryce Schober wrote:
I haven't gotten anything on the crossgcc list, so I'm going to
cross-post this here. FYI, the toolchain is gcc-3.3 / newlib-1.11.0.
Thanks for any advice you can give me.
-------- Original Message --------
Subject: alloc problem?
Date: Wed, 12 Nov 2003 15:12:14 -0800
From: Bryce Schober <bryceman@dpzone.com>
To: crossgcc@sources.redhat.com
Our arm-elf project here has been plagued with problems when trying
to use
sprintf. We've gotten by without it by writing some of our own
conversion
functions, but ideally we'd be able to use c++, which would need use
alloc a
lot. My instinct tells me that alloc is the problem, because the
problems we've
had with sprintf are fairly unpredictable and it's the only function
that we're
using that needs an alloc. Furthermore, I suspect that the root of
the problem
may be our linker script (because the wierd behavior of sprintf has
seemed to
variy with program size at times), but I know little about linker
scripts, and
nothing about what the alloc functions require of one.
Here's our linker script:
SEARCH_DIR("/usr/local/src/arm-elf-gcc-combined/installs-combined/arm-elf/lib");
SECTIONS
{
. = 0x00008000;
ER_RO : { *(ER_RO) }
.text : { *(.text ) }
.rodata : { *(.rodata) }
.data : { *(.data) }
__bss_start__ = .;
.bss : { *(.bss) }
/* __sbss_start = .; */
/*__sbss_end = .; */
__bss_end__ = .;
. += 0x4000;
PROVIDE (__stack = .);
_end = .;
end = .;
/*
.debug_info 0 : { *(.debug_info) }
.debug_abbrev 0 : { *(.debug_abbrev) }
.debug_line 0 : { *(.debug_line) }
.debug_frame 0 : { *(.debug_frame) }
*/
/* .debug_str 0 : { *(.debug_str) } */
/* .debug_loc 0 : { *(.debug_loc) } */
/* .debug_macinfo 0 : { *(.debug_macinfo) } */
}
------------------------------------------------------------------------
GNU ld version 2.11.92 20011103
Supported emulations:
armelf
using internal linker script:
==================================================
/* Default linker script, for normal executables */
OUTPUT_FORMAT("elf32-littlearm", "elf32-bigarm",
"elf32-littlearm")
OUTPUT_ARCH(arm)
ENTRY(_start)
SEARCH_DIR(/notnfs/jjohnstn/arm/arm-elf/lib);
/* Do we need any of these for elf?
__DYNAMIC = 0; */
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==================================================