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                        <h1 id="objdump1"><a class="header" href="#objdump1">objdump(1)</a></h1>
<pre><code class="language-markdown">  objdump [opts] &lt;elf&gt;
    -M intel                   use intil syntax
    -d                         disassemble text section
    -D                         disassemble all sections
    --disassemble=&lt;sym&gt;        disassemble symbol &lt;sym&gt;
    -S                         mix disassembly with source code
    -C                         demangle
    -j &lt;section&gt;               display info for section
    --[no-]show-raw-insn       [dont] show object code next to disassembly
    --visualize-jumps[=color]  visualize jumps with ascii art, optionally color arrows
</code></pre>
<h2 id="disassemble-section"><a class="header" href="#disassemble-section">Disassemble section</a></h2>
<p>For example <code>.plt</code> section:</p>
<pre><code class="language-markdown">  objdump -j .plt -d &lt;elf&gt;
</code></pre>
<h2 id="example-disassemble-raw-binary"><a class="header" href="#example-disassemble-raw-binary">Example: disassemble raw binary</a></h2>
<p>This can be helpful for example as a cheap analysis tool when toying with JIT
generating code. We could just write thee binary code buffer to a file and
disassemble with <code>objdump</code>.</p>
<p>To re-create that case, we just assemble and link some ELF file and then create
a raw binary of the text section with <code>objcopy</code>.</p>
<pre><code class="language-x86asm"># file: test.s
.section .text, "ax"

.global _start
_start:
    xor %rax, %rax
    mov $0x8, %rax
1:
    cmp $0, %rax
    je 2f
    dec %rax
    jmp 1b
2:
    # x86-64 exit(2) syscall
    mov $0, %rdi
    mov $60, %rax
    syscall
</code></pre>
<pre><code class="language-bash"># Assemble &amp; link.
as -o test.o test.s
ld -o test test.o testc.o
# ELF -&gt; binary (only take .text section).
objcopy -O binary --only-section .text test test-bin

# Disassemble raw binary.
objdump -D -b binary -m i386:x86-64 test-bin
</code></pre>
<h2 id="example-disassemble-specific-symbol"><a class="header" href="#example-disassemble-specific-symbol">Example: disassemble specific symbol</a></h2>
<pre><code class="language-bash"># Disassemble main().
objdump --disassemble=main &lt;bin&gt;
# Disassemble 'foo::bar()' (mangled).
objdump --disassemble=_ZN3foo3barEvr &lt;bin&gt;

# Disassemble 'foo::bar()' (demangled), requires -C
objdump -C --disassemble=foo::bar &lt;bin&gt;
</code></pre>

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                        <h1 id="objdump1"><a class="header" href="#objdump1">objdump(1)</a></h1>
<pre><code class="language-markdown">  objdump [opts] &lt;elf&gt;
    -M intel                   use intil syntax
    -d                         disassemble text section
    -D                         disassemble all sections
    --disassemble=&lt;sym&gt;        disassemble symbol &lt;sym&gt;
    -S                         mix disassembly with source code
    -C                         demangle
    -j &lt;section&gt;               display info for section
    --[no-]show-raw-insn       [dont] show object code next to disassembly
    --visualize-jumps[=color]  visualize jumps with ascii art, optionally color arrows
</code></pre>
<h2 id="disassemble-section"><a class="header" href="#disassemble-section">Disassemble section</a></h2>
<p>For example <code>.plt</code> section:</p>
<pre><code class="language-markdown">  objdump -j .plt -d &lt;elf&gt;
</code></pre>
<h2 id="example-disassemble-raw-binary"><a class="header" href="#example-disassemble-raw-binary">Example: disassemble raw binary</a></h2>
<p>This can be helpful for example as a cheap analysis tool when toying with JIT
generating code. We could just write thee binary code buffer to a file and
disassemble with <code>objdump</code>.</p>
<p>To re-create that case, we just assemble and link some ELF file and then create
a raw binary of the text section with <code>objcopy</code>.</p>
<pre><code class="language-x86asm"># file: test.s
.section .text, "ax"

.global _start
_start:
    xor %rax, %rax
    mov $0x8, %rax
1:
    cmp $0, %rax
    je 2f
    dec %rax
    jmp 1b
2:
    # x86-64 exit(2) syscall
    mov $0, %rdi
    mov $60, %rax
    syscall
</code></pre>
<pre><code class="language-bash"># Assemble &amp; link.
as -o test.o test.s
ld -o test test.o testc.o
# ELF -&gt; binary (only take .text section).
objcopy -O binary --only-section .text test test-bin

# Disassemble raw binary.
objdump -D -b binary -m i386:x86-64 test-bin
</code></pre>
<h2 id="example-disassemble-specific-symbol"><a class="header" href="#example-disassemble-specific-symbol">Example: disassemble specific symbol</a></h2>
<pre><code class="language-bash"># Disassemble main().
objdump --disassemble=main &lt;bin&gt;
# Disassemble 'foo::bar()' (mangled).
objdump --disassemble=_ZN3foo3barEvr &lt;bin&gt;

# Disassemble 'foo::bar()' (demangled), requires -C
objdump -C --disassemble=foo::bar &lt;bin&gt;
</code></pre>

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