cross compiling and crtbeginS.o

[Lloyd Parkes <lloyd%must-have-coffee.gen.nz@localhost>]

Hi all,
I'm cross compiling NetBSD for an embedded platform. I've been eyeing  
up the MK* variables listed in share/mk/bsd.README. One that caught  
my eye is MKGCC=no. I won't need to run GCC on the target  
environment, so why waste time compiling it?

There seems to be some confusion over where crtbeginS.o (and  
crtendS.o) fit into the scheme of things.

gnu/lib/crtstuff4/Makefile will not do anything if MKGCC=no with the  
comment "If using an external toolchain, we expect crtbegin/crtend to  
be supplied by that toolchain's run-time support". OK.

share/mk/bsd.lib.mk unconditionally refers to ${_GCC_CRTBEGINS} and $ 
{_GCC_CRTENDS} which in turn seems to cause problems generating  
dependencies because make can't work out how these files should be  
built. I can fix this by putting .if ${MKGCC} != no ... in share/mk/ 
bsd.lib.mk. OK.

Then we fail to create libc.so.12.149 because $TOOLDIR/bin/arm-- 
netbsdelf-gcc doesn't have it's own copy of crtbeginS.o. I created  
one after reading tools/gcc/README.mknative and added an appropriate - 
B flag the link line for libc.so.12.149 at which point libgcc_pic  
couldn't be found.

Is it my imagination, or am I the first person to use MKGCC=no with  
the new(ish) tools infrastructure?

Am I right in guessing that the only real solution is to have a full  
installation of GCC for cross compilation?

Cheers,
Lloyd
p.s. I'm cross compiling from NetBSD/amd64 4.0 to NetBSD/evbarm 4.0,  
but I don't think that will make a difference.