Add nacl-clang testing to SCons

This CL adds a nacl_clang flag to SCons to use nacl-clang.

It adds an implicit dependence on -lpthread to nexes because nacl-clang
always links with it (because libc++ requires it). It's also enabled
for PNaCl; if this ends up working out well for nacl-clang maybe we can
remove the really ugly special-casing for pthread_private in pnacl-ld.

It modifies or disables a few tests, so that everything now build with
nacl-clang (or has a bug filed for why not).

It also ifdefs out the .init and .fini sections from crti/crtn, because
we do not use them with clang.,,

Review URL:

git-svn-id: svn:// fcba33aa-ac0c-11dd-b9e7-8d5594d729c2
1 file changed
tree: 04480add4a961d4a22fb9880c1f89cd5efb665d0
  3. site_tools/