gistfile1.txt

$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc-4.7.2
COLLECT_LTO_WRAPPER=/usr/libexec/gcc/x86_64-pc-linux-gnu/4.7.2/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /var/tmp/portage/sys-devel/gcc-4.7.2/work/gcc-4.7.2/configure --prefix=/usr --bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/4.7.2 --includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.7.2/include --datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.7.2 --mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.7.2/man --infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.7.2/info --with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.7.2/include/g++-v4 --host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu --disable-altivec --disable-fixed-point --without-ppl --without-cloog --enable-lto --enable-nls --without-included-gettext --with-system-zlib --enable-obsolete --disable-werror --enable-secureplt --enable-multilib --with-multilib-list=m32,m64 --enable-libmudflap --disable-libssp --enable-libgomp --with-python-dir=/share/gcc-data/x86_64-pc-linux-gnu/4.7.2/python --enable-checking=release --disable-libgcj --enable-languages=c,c++,objc,fortran --enable-shared --enable-threads=posix --enable-__cxa_atexit --enable-clocale=gnu --enable-targets=all --with-bugurl=http://bugs.gentoo.org/ --with-pkgversion='Gentoo 4.7.2 p1.1, pie-0.5.5'
Thread model: posix
gcc version 4.7.2 (Gentoo 4.7.2 p1.1, pie-0.5.5) 

$ gcc -O2 -c reprod.c
$ objdump -d reprod.o

reprod.o:     file format elf64-x86-64


Disassembly of section .text:

0000000000000000 <memset_internal>:
   0:	55                   	push   %rbp
   1:	48 89 fd             	mov    %rdi,%rbp
   4:	53                   	push   %rbx
   5:	48 89 f3             	mov    %rsi,%rbx
   8:	48 83 ec 18          	sub    $0x18,%rsp
   c:	e8 00 00 00 00       	callq  11 <memset_internal+0x11>
  11:	66 0f 6e c0          	movd   %eax,%xmm0
  15:	48 83 fb 0f          	cmp    $0xf,%rbx
  19:	66 0f 70 c0 51       	pshufd $0x51,%xmm0,%xmm0
  1e:	66 0f 7f 04 24       	movdqa %xmm0,(%rsp)
  23:	76 2b                	jbe    50 <memset_internal+0x50>
  25:	48 8d 73 f0          	lea    -0x10(%rbx),%rsi
  29:	48 8b 14 24          	mov    (%rsp),%rdx
  2d:	48 8b 44 24 08       	mov    0x8(%rsp),%rax
  32:	48 89 ef             	mov    %rbp,%rdi
  35:	48 83 e6 f0          	and    $0xfffffffffffffff0,%rsi
  39:	48 8d 4c 35 10       	lea    0x10(%rbp,%rsi,1),%rcx
  3e:	66 90                	xchg   %ax,%ax

  40:	48 89 17             	mov    %rdx,(%rdi)
  43:	48 89 47 08          	mov    %rax,0x8(%rdi)
  47:	48 83 c7 10          	add    $0x10,%rdi
  4b:	48 39 cf             	cmp    %rcx,%rdi
  4e:	75 f0                	jne    40 <memset_internal+0x40>

  50:	48 83 c4 18          	add    $0x18,%rsp
  54:	5b                   	pop    %rbx
  55:	5d                   	pop    %rbp
  56:	c3                   	retq   

Disassembly of section .text.startup:

0000000000000000 <main>:
   0:	48 83 ec 28          	sub    $0x28,%rsp
   4:	be 10 00 00 00       	mov    $0x10,%esi
   9:	48 8d 7c 24 01       	lea    0x1(%rsp),%rdi
   e:	e8 00 00 00 00       	callq  13 <main+0x13>
  13:	0f b6 54 24 10       	movzbl 0x10(%rsp),%edx
  18:	be 00 00 00 00       	mov    $0x0,%esi
  1d:	bf 01 00 00 00       	mov    $0x1,%edi
  22:	31 c0                	xor    %eax,%eax
  24:	e8 00 00 00 00       	callq  29 <main+0x29>
  29:	31 c0                	xor    %eax,%eax
  2b:	48 83 c4 28          	add    $0x28,%rsp
  2f:	c3                   	retq