i386-Options - Using as

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#### 8.12.1 Options

The i386 version of `as` has a few machine dependent options:

`--32 | --64`
  Select the word size, either 32 bits or 64 bits. Selecting 32-bit implies Intel i386 architecture, while 64-bit implies AMD x86-64 architecture.

  These options are only available with the ELF object file format, and require that the necessary BFD support has been included (on a 32-bit platform you have to add –enable-64-bit-bfd to configure enable 64-bit usage and use x86-64 as target platform).

`-n`
  By default, x86 GAS replaces multiple nop instructions used for alignment within code sections with multi-byte nop instructions such as leal 0(%esi,1),%esi. This switch disables the optimization.