5.7.12 Options for Code Generation Conventions

The options tabulated below control machine-independent conventions used when generating code and are discussed in the sections that follow.

Table 5-21. Code Generation Convention Options
Option (links to explanatory section)	Definition
`-fargument-alias` `-fargument-noalias` `-fargument-noalias-global`	Specify the possible relationships among parameters and between parameters and global data.
`-fcall-saved-reg`	Treat `reg` as an allocatable register saved by functions.
`-fcall-used-reg`	Treat `reg` as an allocatable register that is clobbered by function calls.
`-f[no-]common`	Controls the placement of global variables defined without an initializer.
`-f[no-]exceptions`	Generate extra code to propagate exceptions.
`-ffixed-reg`	Treat`reg` as a fixed register that will not be used in code.
`-f[no-]ident`	Ignore the `#ident` directive.
`-fpack-struct`	Pack all structure members together without memory holes.
`-f[no-]pcc-struct- return`	Return short `struct` and `union` values in memory, rather than in registers.
`-f[no-]short-enums`	Specify the size of `enum` types.
`-f[no-]verbose-asm`	Put extra commentary information in the generated assembly code to make it more readable.