low level optimization

[Michael Coffin]

In article <21703 at lanl.gov> jlg at cochiti.lanl.gov (Jim Giles) writes:
>For a language which requires
>separate compilation, _NO_OTHER_INFORMATION_ is known about an
>external procedure.  The reason is that _all_ other characteristics
>of an external procedure are allowed to _change_ without the need to
>recompile any uses of that procedure.

The C standard doesn't say Thou Must Compile Separately.  It says that
the meaning of the program---roughly speaking, the output obtained by
running the program---doesn't depend on information gleaned from
intermodule analysis.  Nothing in the standard says that a compiler
can't take advantage of all available information to produce good
code.

-mike