Re: porting gcc

Juergen Fischer <bm216754@muenchen.org> wrote:


> I heard about the possibility of a c++ -> c translator. however my
> theory is that c++ exceptions need capabilities beyond stack
> operations expressible in C,


The cleanest way to translate C++ into C would be to translate
function by function, with each C++ function becoming a unique C
function. I've heard that C-front followed that approach and ran into
the problems that you describe.


There is a lower level approach wherein C is treated as an assembly
language for a load/store architecture:
  * variables are treated as registers
  * a byte array is treated as memory
  * a char* pointer variable serves as stack pointer
  * indirect jumps are implemented via a switch-based hack
and so on.


Anything that can be done in say MIPS assembly language can be done
with this approach. One bit of tedium is that in the resulting C code
labels are function local, so one must merge the .c files resulting
from individual C++ translation units into a single very big main()
function. Also, linking to standard library functions is a tedious
but solvable problem.


Tom Payne

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