DWARF debug info unit tests: Tests for wrong triple?

The DWARF debug info unit tests in llvm/unittests/DebugInfo/DWARF/ forms a generator based on the host triple. This is problematic for cross-compile configurations where LLVM does not fully support code generation for the host platform.

I have found no rationale for why the host triple was chosen (ref: https://reviews.llvm.org/D27326?id=80002#inline-236026).

I would imagine that it is more useful to test for the default target rather than the host.

– HT

Adding in aprantl here to make sure he's aware.

Making sure I understand - you're building a compiler on machine a
that llvm doesn't support code generation to and running the llvm
tests on that platform?

That's probably a bit out of what any of us expected here as the
typical one is to use build llvm on a platform that it already
supports. I do agree that default target would also work here as a
suitable test.

-eric

Am I right in assuming that the default target is the host triple for a typical non-cross compiler that most of us (or rather our bots) typically build? If yes then it sounds like changing the default triple to the default target would be a noop for most of us and thus a reasonable change?

-- adrian

Yes, that is correct.

Adding in aprantl here to make sure he’s aware.

Making sure I understand - you’re building a compiler on machine a
that llvm doesn’t support code generation to and running the llvm
tests on that platform?

Yes, or rather the support is in-progress, but the host platform should be good for hosting a cross-compiling LLVM toolchain.

+1. We run a cross-compile environment but as it’s the same target architecture as our hosts, we don’t run into quite the same issue; but I would like to see the unittests pay attention to the default target triple.

Note there are some builds that do not have a default target triple, so you’ll want to do something sensible there.

–paulr

+1. We run a cross-compile environment but as it’s the same target architecture as our hosts, we don’t run into quite the same issue; but I would like to see the unittests pay attention to the default target triple.

Note there are some builds that do not have a default target triple, so you’ll want to do something sensible there.

Thanks for the tip. I’ll keep that in mind.

– HT