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copied!<p>I suspect the problem has something to do with your code setting <code>rax</code> to <code>0</code> whereas it must be <code>1</code> because you pass a floating point argument (see <a href="https://stackoverflow.com/a/6212835/249230">here</a> for details). Basically <code>rax</code> should contain the number of variable arguments passed in <code>xmmN</code> registers.</p> <p>Edit:</p> <p>The crash in <code>printf</code> seems to be caused by stack miaslignment as the program crashes at a <code>movaps</code> instruction (which expects the memory operand to be aligned on 16-byte boundary):</p> <pre><code>=> 0x7ffff7a65f84 <__printf+36>: movaps %xmm0,0x50(%rsp) 0x7ffff7a65f89 <__printf+41>: movaps %xmm1,0x60(%rsp) 0x7ffff7a65f8e <__printf+46>: movaps %xmm2,0x70(%rsp) 0x7ffff7a65f93 <__printf+51>: movaps %xmm3,0x80(%rsp) 0x7ffff7a65f9b <__printf+59>: movaps %xmm4,0x90(%rsp) 0x7ffff7a65fa3 <__printf+67>: movaps %xmm5,0xa0(%rsp) 0x7ffff7a65fab <__printf+75>: movaps %xmm6,0xb0(%rsp) 0x7ffff7a65fb3 <__printf+83>: movaps %xmm7,0xc0(%rsp) </code></pre> <p>When entering <code>main</code> the stack is not 16-byte aligned but if you fix this the program works fine. Below is my test program (notice the <code>sub rsp, 8</code> in the beginning):</p> <pre><code>global main extern printf section .data string db `%f\n`, 0 rs dq 1.6 section .text main: sub rsp, 8 movq xmm0, qword [rs] mov rdi, string mov rax, 1 call printf add rsp, 8 mov eax, 0x60 xor edi, edi syscall </code></pre>

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