[cfe-dev] Library search paths on biarch systems

[Chandler Carruth]

On Thu, Dec 26, 2013 at 9:04 PM, Jonathan Roelofs <jonathan at codesourcery.com
> wrote:

> Hi,
>
> I noticed that the Linux toolchain also adds the default multilib to the
> search path when targeting the "other" multilib that the biarch gcc
> installation supports.  For example, in a gcc installation providing two
> multilibs: '.;@m32' and '64;@m64', when -m64 is specified on the clang
> command line, both <gcc>/<triple>/<ver>/64/ and <gcc>/<triple>/<ver>/ are
> added to the search paths (There's a couple of tests for this specific case
> in clang/test/Driver/linux-ld.c:109 and clang/test/Driver/cross-linux.
> c:57).
>
> Is this correct for the opposite case (i.e. gcc providing '.;@m64' and
> '32;@m32' with -m32 on the command line) for which there don't seem to be
> any tests for or against it? How about on PPC64?
>

A long time ago, I built GCC installs and created as many directories as I
could (even if empty) to try to test all of the search paths that it ended
up using. It *appeared* at the time that this was intentional, and it made
everything more complex to be asymmetrical here. I would rather keep the
symmetry to simplify the code and logic unless doing so breaks something
really horrible.

Similarly, I'm hoping desperately that we can have the same biarch search
pattern for PPC, x86, mips, and whatever other biarch toolchains we end up
with. I don't want to start having different logic for each cpu type...
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20131226/e00c10a1/attachment.html>