Re: deadcode optimization

> This is not so easy: what about static variables ? You can rename
> them, but you will break debugger compatibility...


It is that easy. Modula-2 and Ada support situations just like C
static variables. No need to declare anything static, it just happens
automatically. The compiler handles this easily since all globals in a
compilation unit go into a single object which only has one bss and/or
data section. This object is the one I mentioned previously that all
other objects in the compilation unit archive refer to. Therefore the
compiler knows the address of all globals within a module via their
offset from the start of that modules bss or data section. Fixups are
output relative to the start of the data or bss section. A special
public symbol is defined that is given offset 0 from the start of the
relevant section.


I know C compiler have used the concept of local symbols but I have
never seen the need. But then C does not support compilation units
so...


--
Norman Black
Stony Brook Software


> >"Smart linking" is trivial for a compiler do handle and have ALL
> >linkers in existence support the unused code "removal".
> >
> >All that need be done is have the compiler output library/archive
> >files directly with one procedure per object in the library. Our
> >compilers have done this since 1987 and any linker appropriately does
> >not link in unused code.

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