Re: compile on AIX 5.3 for AIX 4.3 - is crosscompiler required?

[Ian Lance Taylor <iant at google dot com>]

JÄdrzej Dudkiewicz <jedrzej.dudkiewicz@gmail.com> writes:

> my setup is as follows: I have one (relatively) fast IBM machine with
> AIX 5.3, and veeery old one with AIX 4.3. The slower machine is The
> Target - I must compile software for it. Testing software on 4.3
> machine is acceptable, but compilation isn't - it has, if I recall
> correctly, 128MB of RAM and 120MHz CPU and software is written in such
> way, that change in one header usualy forces recompilation of half of
> a project. So I'd like to compile on AIX 5.3 for AIX 4.3 - do I need a
> cross-compiler? Or should I build with -march=... (or similar) set to
> target's configuration and just link on older machine? Or it will work
> only if I'm lucky? If I do need a cross-compiler, where should I
> start?

I guess the question is whether programs compiled for AIX 4.3 can run on
AIX 5.3.  If they can, then you don't need a cross-compiler.  What you
need to do is copy all the header files and libraries over to your AIX
5.3 machine, and then build a compiler using the configure options
--with-sysroot and --with-build-sysroot and set --build, --host and
--target to CPU-aix4.3.  I don't know if it will work but it seems worth
a try.  Oh yeah, also copy over the assembler, linker, etc.  In fact,
heck, you could just build the compiler on AIX 4.3, then copy the whole
environment over to AIX 5.3 and run it there.  Building the compiler
will be slow, but using it won't be.  That might be the easiest approach
of all.

Ian