[LLVMdev] cross-compiling current trunk fails

[Tim Northover]

> That's odd. I never had problems with a parallel build.
>
> Ideas?

I've seen similar failures, though oddly with CMake. What I decided
was happening is that the Makefile knows it has to build llvm-tblgen,
but not quite what depends on it for some reason.

In the -j10 case, it's encounters something that needs llvm-tblgen
before it's actually built it. In the -j1 case it tries to configure &
build llvm-tblgen, but (presumably) needs a different, native,
compiler and discovers your host's one is too old.

So to solve the -j1 build, you probably do want to upgrade your native
compiler, unless it's being misdetected.

For the parallel issue, my build-script knowledge was too small to fix
it back then. I ended up running at -j1 mostly, though I've since had
success with the CMake variables LLVM_TABLEGEN and CLANG_TABLEGEN, by
pointing them at a (recent!) native TableGen I've had lying around.
Not foolproof, but often enough for a quick build/test.

Cheers.

Tim.