How to make objdump show assembly of sections only appeared in source code?

Question

I would like to produce assemblies like the one in the answer of this question Using GCC to produce readable assembly?

for simple test code: test.c

void main(){
   int i;
   for(i=0;i<10;i++){
   printf("%d\n",i);
   }
}

gcc command : gcc -g test.c -o test.o

objdump command: objdump -d -M intel -S test.o

But what i got is assemblies starts with .init section 080482bc<_init>: and end with .fini section 080484cc<_fini>

which i do not want them to be shown.

why is this happening ? and how can i avoid showing sections that are not in the source file?

You can use grep (assuming you are using Linux) to search the disassembly for the section you want to see, such as: ` objdump -D test.out | grep -A20 main.: ` This will only show you the first 20 lines from the main section. — Janman, Oct 19 '13 at 16:10

score 6 · Accepted Answer · answered Oct 19 '13 at 16:09

6

Right now you're creating an executable file and not an object file. The executable file of course contains lot of extra sections.

If you want to create an object file, use the -c flag to GCC.

answered Oct 19 '13 at 16:09

score 3 · Answer 2 · answered Oct 19 '13 at 16:17

3

You can specify sections using -j option.

So objdump -d executable -j .text -j .plt will only show disassembly from .text and .plt sections.

answered Oct 19 '13 at 16:17

wkordalski

2 Answers2