Stack Overflow
Stack Overflow

Questions tagged [disassembly]

Involves turning "compiled" code (such as machine code, byte code or IR code) back in higher-level assembly mnemonics.

Disassembly is the process for turning a binary form back into its higher-level counterpart so that it can be inspected or altered in a human-readable form.

This is normally done with the aid of a disassembler, some notable examples being:

1640 questions
523
votes
17 answers

How do you get assembler output from C/C++ source in GCC?

How does one do this? If I want to analyze how something is getting compiled, how would I get the emitted assembly code?
Doug T.
  • 64,223
  • 27
  • 138
  • 202
170
votes
8 answers

How to decompile an APK or DEX file on Android platform?

Is it possible to decompile an APK package or DEX file on Android platform? Are there any tools that can decompile an APK file?
user3151261
  • 1,947
  • 2
  • 13
  • 12
157
votes
14 answers

How can I see the assembly code for a C++ program?

How can I see the assembly code for a C++ program? What are the popular tools to do this?
Geek
  • 23,089
  • 20
  • 71
  • 85
133
votes
10 answers

How to disassemble a binary executable in Linux to get the assembly code?

I was told to use a disassembler. Does gcc have anything built in? What is the easiest way to do this?
Syntax_Error
  • 5,964
  • 15
  • 53
  • 73
114
votes
11 answers

How to disassemble one single function using objdump?

I've got a binary installed on my system, and would like to look at the disassembly of a given function. Preferrably using objdump, but other solutions would be acceptable as well. From this questions I've learned that I might be able to disassemble…
MvG
  • 57,380
  • 22
  • 148
  • 276
100
votes
2 answers

What does @plt mean here?

0x00000000004004b6 : callq 0x400398 Anyone knows? UPDATE Why two disas printf give me different result? (gdb) disas printf Dump of assembler code for function printf@plt: 0x0000000000400398 : jmpq …
gdb
  • 7,189
  • 12
  • 38
  • 36
72
votes
5 answers

How to write a disassembler?

I'm interested in writing an x86 dissembler as an educational project. The only real resource I have found is Spiral Space's, "How to write a disassembler". While this gives a nice high level description of the various components of a…
mmcdole
  • 91,488
  • 60
  • 186
  • 222
71
votes
11 answers

How to disassemble a memory range with GDB?

I'm trying to disassemble a program to see a syscall assembly instruction (the INT instruction, I believe) and the handler with GDB and have written a little program (see below) for it that opens and closes a file. I was able to follow the call to…
Patrick
  • 4,720
  • 4
  • 41
  • 71
68
votes
8 answers

How to disassemble, modify and then reassemble a Linux executable?

Is there anyway this can be done? I've used objdump but that doesn't produce assembly output that will be accepted by any assembler that I know of. I'd like to be able to change instructions within an executable and then test it afterwards.
FlagCapper
  • 799
  • 1
  • 6
  • 5
64
votes
2 answers

How does GCC optimize out an unused variable incremented inside a loop?

I wrote this simple C program: int main() { int i; int count = 0; for(i = 0; i < 2000000000; i++){ count = count + 1; } } I wanted to see how the gcc compiler optimizes this loop (clearly add 1 2000000000 times should be…
Haile
  • 3,120
  • 3
  • 24
  • 40
59
votes
2 answers

What is your favorite disassembler tool in Mac OS X?

I am using the otool, nm and Fraise text editor to disassemble the Mach-o binaries. My workflow at this point is pretty straightforward: 1. List the existed symbols. nm -g 2. Get the disasm code. otool -vt 3. Copy and paste this output to a…
user663896
55
votes
2 answers

Disassembling A Flat Binary File Using objdump

Can I disassemble a flat binary file using objdump? I'm familiar with disassembling a structured binary executable such as an ELF file using: objdump -d file.elf But if I have a flat binary file that I know is supposed to be loaded at, e.g.,…
Multimedia Mike
  • 12,660
  • 5
  • 46
  • 62
53
votes
3 answers

Why does this memory address %fs:0x28 ( fs[0x28] ) have a random value?

I've written a piece of C code and I've disassembled it as well as read the registers to understand how the program works in assembly. int test(char *this){ char sum_buf[6]; strncpy(sum_buf,this,32); return 0; } The piece of my code…
Dr.Knowitall
  • 10,080
  • 23
  • 82
  • 133
45
votes
1 answer

Long multi-byte NOPs: commonly understood macros or other notation

It's not a big secret that x86 (and x86_64) processors have not only the single-byte NOP instruction, but also various types of multi-byte NOP-like instructions. These are the ones I've managed to find: Recommended by AMD, ref. AMD Software…
GreyCat
  • 16,622
  • 18
  • 74
  • 112
40
votes
2 answers

Find out what functions a static C library has

I have a static C library (say mylib.a) and I was wondering if it's possible to find out what functions are implemented inside that file. I don't have a corresponding header file. what I need is like the equivalent of javap for Java.
cd1
  • 15,908
  • 12
  • 46
  • 47
1
2 3
…
99 100