I tried but failed....

++++++++++++++++++++++++++++
# arm-elf-gcc -Wall -O2 -elf2flt -c test2.c
# arm-elf-objdump test2.o -x

test2.o: file format elf32-littlearm
test2.o
architecture: arm, flags 0x00000011:
HAS_RELOC, HAS_SYMS
start address 0x00000000
???? = 0: [APCS-32]

Sections:
Idx Name Size VMA LMA File off Algn
0 .text 00000014 00000000 00000000 00000034 2**2
CONTENTS, ALLOC, LOAD, RELOC, READONLY, CODE
1 .data 00000000 00000000 00000000 00000048 2**0
CONTENTS, ALLOC, LOAD, DATA
2 .bss 00000000 00000000 00000000 00000048 2**0
ALLOC
3 .comment 00000012 00000000 00000000 00000048 2**0
CONTENTS, READONLY
SYMBOL TABLE:
00000000 l df *ABS* 00000000 test2.c
00000000 l d .text 00000000
00000000 l d .data 00000000
00000000 l d .bss 00000000
00000000 l d .comment 00000000
00000000 g F .text 00000014 main


RELOCATION RECORDS FOR [.text]:
OFFSET TYPE VALUE
00000010 R_ARM_PC24 .text

[root@localhost root]# arm-elf-ld test2.o
arm-elf-ld: warning: cannot find entry symbol _start; defaulting to 00008000
++++++++++++++++++++++++++++

What's happened?

+++++++++++++++++++++
arm-elf ld hello.o -e 0x00000000

download it to Embedix linux and run
but get this message "Segmentation fault"

> I tried but failed....
>
> ++++++++++++++++++++++++++++
> # arm-elf-gcc -Wall -O2 -elf2flt -c test2.c
> # arm-elf-objdump test2.o -x

You've compiled test2.c into an object file, but you haven't linked it so arm-elf-objdump shows you a dump of just the object file, and not a fully-linked program. Try:

# arm-elf-gcc -Wall -O2 -elf2flt -c test2.c
# arm-elf-gcc -o test2 test2.o -Wl,-Map test2.map
# arm-elf-objdump test2 -x

the 'arm-elf-gcc -o test2 test2.o' will link test2.o with the standard startup files and create a full-linked executable. the '-wl,-Map test2.map' instructs the linke to create a linker map file which will show what is linked with test2.o

I tried follow you:

++++++++++++++++++++++++++
#arm-elf-gcc test2.c -c -Wall -elf2flt -O2
#arm-elf-ld test2.o -o test2 -Map test.map
arm-elf-ld:warning:cannot find entry symbol _start:defaulting to 0x00008000
#arm-elf-ld test2.o -o test2 -Map test.map -entry 0x00008000
and
result of executing in Embedix linux: "segmentation fault"

//test.map start
Memory Configuration

Name Origin Length Attributes
*default* 0x00000000 0xffffffff

Linker script and memory map

LOAD test2.o
0x00008000 .=0x8000
.
.
.

.stack 0x00080000 0x0
0x00080000 _stack=.
*(.stack)
OUTPUT(test2 elf32-littlearm)
//test.map end
+++++++++++++++++++++++

I puzzled what's wrong with it
Why is the result always "Segmentation fault"?
How can I creat a correct binary file to run on the Embedix linux?

>I tried follow you:
>
>++++++++++++++++++++++++++
>#arm-elf-gcc test2.c -c -Wall -elf2flt -O2
>#arm-elf-ld test2.o -o test2 -Map test.map
>arm-elf-ld:warning:cannot find entry symbol _start:defaulting to 0x00008000

you need to use 'arm-elf-gcc -o test2 test2.o' to link your program since the compiler invokes the linker with other libraries and startup code necessary for your program to run.

Please see my previous message and try the commands I gave there.

first I tried follow you, but it doesn't work

++++++++++++++++++++++++
arm-elf-gcc -o hello hello.c -O2
/usr/bin/../lib/gcc-lib/arm-elf/3.2.1/../../../../arm-elf/bin/ld: cannot open crt0.o: ?????????
collect2: ld returned 1 exit status

# arm-elf-gcc -Wall -O2 -elf2flt -c hello.c
# arm-elf-gcc -o hello hello.o -Wl,-Map hello.map -nostdlib
It can create the "hello" binary file
but it doesn't work normally,print disordered code
+++++++++++++++++++++++++
Can anyone show me a whole process from assembly to linking, correct running.
Is there any problems in my compile environment?

Wait a minute. You are trying to build a program to run on a "linux" system?

If so, then you want to use arm-linux-gcc compiler, not the arm-elf-gcc compiler.
This is because the arm-linux compiler is configured to us relocatable code, and to link in particualar startup files to handle initializion and exit correctly.

Tray instead:

# arm-linux-gcc -O -Wall -c test2.c
# arm-linux-gcc -o test2 test2.o -Wl,-Map test2.map

Which should produce test2 which should run on your LH79520 linux board(assuming the linux tools were properly configured).