include *any* path on crtbegin.o unless we actually find such a file via
one of the search paths. We still strictly check the search paths right
after this, so we'll catch any issues there.

The reason for this is that the driver does some normalization of the
path on the actual object file, and this changes the textual format of
the string on Windows. It no longer matches the textual format of the
sysroot flag.

llvm-svn: 140998

any distros that use this, building a multilib GCC from mainline will
install linker scripts here.

llvm-svn: 140996

This requires fixing a latent bug -- if we used the default host triple
instead of an autodetected triple to locate GCC's installation, we
didn't go back and fix the GCC triple. Correct that with a pile of
hacks. This entire routine needs a major refactoring which I'm saving
for a subsequent commit. Essentially, the detection of the GCC triple
should be hoisted into the same routine as we locate the GCC
installation: the first is intrinsically tied to the latter. Then the
routine will just return the triple and base directory.

Also start to bring the rest of the library search path logic under
test, including locating crtbegin.o. Still need to test the multilib and
other behaviors, but there are also bugs in the way of that.

llvm-svn: 140995

This is still very much a WIP, but sysroot was completely broken before
this so we are moving closer to correctness.

The crux of this is that 'ld' (on Linux, the only place I'm touching
here) doesn't apply the sysroot to any flags given to it. Instead, the
driver must translate all the paths it adds to the link step with the
system root. This is easily observed by building a GCC that supports
sysroot, and checking its driver output.

This patch just fixes the non-multilib library search paths. We should
also use this in many other places, but first things first.

This also allows us to make the Linux 'ld' test independent of the host
system. This in turn will allow me to check in test tree configurations
based on various different distro's configuration. Again, WIP.

llvm-svn: 140990

precisely match the pattern and logic used by the GCC driver on Linux as
of a recent SVN checkout.

This happens to follow a *much* more principled approach. There is
a strict hierarchy of paths examined, first with multilib-suffixing,
second without such suffixing. Any and all of these directories which
exist will be added to the library search path when using GCC.

There were many places where Clang followed different paths, omitted
critical entries, and worst of all (in terms of challenges to debugging)
got the entries in a subtly wrong order.

If this breaks Clang on a distro you use, please let me know, and I'll
work with you to figure out what is needed to work on that distro. I've
checked the behavior of the latest release of Ubuntu, OpenSUSE, Fedora,
and Gentoo. I'll be testing it on those as well as Debian stable and
unstable and ArchLinux. I may even dig out a Slackware install.

No real regression tests yet, those will follow once I add enough
support for sysroot to simulate various distro layouts in the testsuite.

llvm-svn: 140981

Make the suffixes optional everywhere, and just make sure they have the
right value. The suffixes aren't the interesting part of this test
anyways.

Sorry for the churn as I let the bots try out various patterns.

llvm-svn: 140927

run it.

llvm-svn: 140925

llvm-svn: 140920

left a FIXME to go track down more distros and see if 'lib' is ever the
64-bit half.

This should hopefully appease the build bots.

llvm-svn: 140915

llvm-svn: 140913

invocations on Linux.

llvm-svn: 140909