These versions contain fixes relevant to mingw/clang.
Do the svn rebase (only necessary for getting sensible llvm/clang
version numbers in clang --version) before checking out the specific
version, otherwise we always end up at the latest master version.
llvm and clang have got new patches that are relevant for mingw
and arm64/win.
compiler-rt has changed things, so we can't ask it to build builtins
for i686 any longer, but need to request it for i386 instead - and
clang will expect it to be named i386 even though we're invoking it
with an i686 target.
This has now been committed upstream in the master branch (we
check out the master branch of compiler-rt, not the 3.9 branch),
in SVN rev 287465 (git mirror commit 8134888c4d01).
The second one, for msvc mode (which vlc doesn't need anyway), isn't
necessary now that llvm has been patched to emit calls properly using
the msvc helper function names.
This fixes up handling of divisions on ARM/Windows, and consistently
does calls to helper functions using the windows/msvc names, instead
of the libgcc naming.
The 3.8 branch produces broken code for divisions on arm/windows.
The brokenness can appear as incorrect behaviour or crashes.
The 3.9 branch isn't released yet, but is probably a better target
to base any work on at the moment.
The previously existing patch needed some modifications to fit
on top of lld 3.9.
Patch 2 makes sure that one still can use the lld built in this
way for linking in MSVC mode.
Patch 3 fixes linking binaries larger than 4 MB or so (previously
the binaries linked fine but didn't work).
Patch 4 makes sure to error out if the relocations are too far
away (instead of producing a broken binary), which happens after
16 MB.
Patch 5 fixes relocations that have an offset, which probably
happens in hand-written assembly (in libav).
Patches 1 and 2 fix a bug (that has been present in 3.7 and 3.8)
where it can use the wrong instruction in some cases (libav
with inline assembly disabled), causing rounding errors in
integer audio dct's there.
Patch 3 allows building inline assembly with clang/llvm in MSVC mode.
Martin Storsjö