Re: [PATCH] fix wrapper auto detection in configure

[Rich Felker <dalias@libc.org>]

On Fri, Jan 22, 2016 at 10:56:03PM +0100, Szabolcs Nagy wrote:
> the libc header based test is wrong if there are no such headers on the
> system only a free standing cc, which should be enough for a musl build.

I'm trying to understand the usage case you're concerned about. Is it
failing to build the wrapper for a glibc-targeted toolchain that
doesn't actually have glibc installed? Is there a reason you woul want
the wrapper in this case?

> check for *-musl* in the target triplet instead.

I don't think we depend on the target tuple at all now except as a way
of identifying the arch. It's only available with gcc, not other
compilers that lack -dumpmachine. I was actually thinking about this
issue a couple days ago and wonder if we should instead check for
predefined macros defined in the psABI for each arch to determine the
arch. This would also work on non-gcc compilers so you don't have to
manually pass the target arch (or tuple) to configure for them.

Anyway if I can understand what real problem you're trying to solve
maybe I can come up with a better approach that doesn't expend
dependency on having a named target tuple.

Rich