# Image Structure and Generation

```{contents}
:local: true
```

## Processor-specific flags

Processor-specific flags are stored in the `e_flags` field of the ELF header. `eld` will set these flags according to the emulation specified or inferred from its inputs. The following are special cases for the `e_flags` field:

1. A lone empty object file:

   ```
   touch empty.o
   ld.eld empty.o -m<emulation>
   llvm-readelf -h a.out
   ```

   The output file will have flags set according to the emulation specified.

2. A symbol definition file:

   ```
   ld.eld -m<emulation> symbols.def
   ```

   The output file will have flags set according to the emulation specified.

3. A lone binary file:

   ```
   ld.eld -m<emulation> --format=binary foo.bin
   llvm-readelf -h a.out
   ```

   Flags are always 0 regardless of the emulation specified.