Upgrade source-build to BB2 for Julia 1.3

[Gnimuc]

Now, we don't need to compile LLVM/Clang locally when building Julia, it feels insane to turn off USE_BINARYBUILDER and wait for 1h+ to use Cxx.jl. This PR upgrades BuildBootstrap.Makefile to reuse LLVM/Clang binaries from LLVMBuilder. With this PR, building Cxx.jl itself only takes <5min on my machine. :P

BTW, #407 and #434 are also merged into this PR for testing. To test this PR, simply building Julia release-1.3 from source(DO NOT set USE_BINARYBUILDER=0) and dev, checkout, build Cxx in REPL.

close #435, close #437, close #441

cc @musm @goretkin @oschulz @christianpeel @GlenHenshaw @MaximeBouton

[MaximeBouton]

I will give it a try, what are the chances that we could merge the changes from #425 as well?
All the check boxes are not ticked but it has been working fine for me on windows with julia 1.2.

[Gnimuc]

＠MaximeBouton I'm going to rebase #425 on the current master branch and release new libcxxffi binaries for Julia 1.3. Source-build for Windows is out of the scope of this PR.

[alhirzel]

There are CI failures related to the location of clang_constants.jl and I am also experiencing the following issue when I manually fix the clang_constants.jl path:

   _       _ _(_)_     |  Documentation: https://docs.julialang.org
  (_)     | (_) (_)    |
   _ _   _| |_  __ _   |  Type "?" for help, "]?" for Pkg help.
  | | | | | | |/ _` |  |
  | | |_| | | | (_| |  |  Version 1.3.0 (2019-11-26)
 _/ |\__'_|_|_|\__'_|  |  Official https://julialang.org/ release
|__/                   |

julia> using Cxx
[ Info: Precompiling Cxx [a0b5b9ef-44b7-5148-a2d1-f6db19f3c3d2]
free(): invalid pointer

signal (6): Aborted
in expression starting at /home/ahirzel/prj/asdf/g/dev/Cxx/src/Cxx.jl:178
gsignal at /usr/lib/libc.so.6 (unknown line)
abort at /usr/lib/libc.so.6 (unknown line)
__libc_message at /usr/lib/libc.so.6 (unknown line)
malloc_printerr at /usr/lib/libc.so.6 (unknown line)
_int_free at /usr/lib/libc.so.6 (unknown line)
_ZN4llvm19SmallPtrSetImplBase4GrowEj at /home/ahirzel/prj/dotfiles/scripts/bin/julia-1.3.0/bin/../lib/julia/libLLVM-6.0.so (unknown line)
_ZN4llvm19SmallPtrSetImplBase14insert_imp_bigEPKv at /home/ahirzel/prj/dotfiles/scripts/bin/julia-1.3.0/bin/../lib/julia/libLLVM-6.0.so (unknown line)
_ZN4llvm11LLVMContext9addModuleEPNS_6ModuleE at /home/ahirzel/prj/dotfiles/scripts/bin/julia-1.3.0/bin/../lib/julia/libLLVM-6.0.so (unknown line)
_ZN4llvm6ModuleC1ENS_9StringRefERNS_11LLVMContextE at /home/ahirzel/prj/dotfiles/scripts/bin/julia-1.3.0/bin/../lib/julia/libLLVM-6.0.so (unknown line)
finish_clang_init at /home/ahirzel/prj/asdf/g/dev/Cxx/src/../deps/usr/lib/libcxxffi.so (unknown line)
init_clang_instance at /home/ahirzel/prj/asdf/g/dev/Cxx/src/../deps/usr/lib/libcxxffi.so (unknown line)
#setup_instance#20 at /home/ahirzel/prj/asdf/g/dev/Cxx/src/initialization.jl:38
#setup_instance at ./tuple.jl:0 [inlined]
__init__ at /home/ahirzel/prj/asdf/g/dev/Cxx/src/initialization.jl:427
unknown function (ip: 0x668cc9e97a9b)
_jl_invoke at /buildworker/worker/package_linux64/build/src/gf.c:2141 [inlined]
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2305
jl_apply at /buildworker/worker/package_linux64/build/src/julia.h:1631 [inlined]
do_call at /buildworker/worker/package_linux64/build/src/interpreter.c:328
eval_value at /buildworker/worker/package_linux64/build/src/interpreter.c:417
eval_stmt_value at /buildworker/worker/package_linux64/build/src/interpreter.c:368 [inlined]
eval_body at /buildworker/worker/package_linux64/build/src/interpreter.c:778
jl_interpret_toplevel_thunk_callback at /buildworker/worker/package_linux64/build/src/interpreter.c:888
unknown function (ip: 0xfffffffffffffffe)
unknown function (ip: 0x668ce4005c0f)
unknown function (ip: 0xffffffffffffffff)
jl_interpret_toplevel_thunk at /buildworker/worker/package_linux64/build/src/interpreter.c:897
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:814
jl_eval_module_expr at /buildworker/worker/package_linux64/build/src/toplevel.c:181
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:640
jl_eval_module_expr at /buildworker/worker/package_linux64/build/src/toplevel.c:181
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:640
jl_parse_eval_all at /buildworker/worker/package_linux64/build/src/ast.c:873
jl_load at /buildworker/worker/package_linux64/build/src/toplevel.c:878
include at ./boot.jl:328 [inlined]
include_relative at ./loading.jl:1105
include at ./Base.jl:31
_jl_invoke at /buildworker/worker/package_linux64/build/src/gf.c:2135 [inlined]
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2305
jl_apply at /buildworker/worker/package_linux64/build/src/julia.h:1631 [inlined]
do_call at /buildworker/worker/package_linux64/build/src/interpreter.c:328
eval_value at /buildworker/worker/package_linux64/build/src/interpreter.c:417
eval_stmt_value at /buildworker/worker/package_linux64/build/src/interpreter.c:368 [inlined]
eval_body at /buildworker/worker/package_linux64/build/src/interpreter.c:778
eval_body at /buildworker/worker/package_linux64/build/src/interpreter.c:705
jl_interpret_toplevel_thunk_callback at /buildworker/worker/package_linux64/build/src/interpreter.c:888
unknown function (ip: 0xfffffffffffffffe)
unknown function (ip: 0x668ce380498f)
unknown function (ip: 0x2)
jl_interpret_toplevel_thunk at /buildworker/worker/package_linux64/build/src/interpreter.c:897
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:814
jl_toplevel_eval_in at /buildworker/worker/package_linux64/build/src/toplevel.c:843
eval at ./boot.jl:330 [inlined]
eval at ./client.jl:425
_jl_invoke at /buildworker/worker/package_linux64/build/src/gf.c:2135 [inlined]
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2305
top-level scope at ./none:3
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:808
jl_toplevel_eval_flex at /buildworker/worker/package_linux64/build/src/toplevel.c:764
jl_toplevel_eval_in at /buildworker/worker/package_linux64/build/src/toplevel.c:843
eval at ./boot.jl:330
_jl_invoke at /buildworker/worker/package_linux64/build/src/gf.c:2135 [inlined]
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2305
exec_options at ./client.jl:263
_start at ./client.jl:460
jfptr__start_2084.clone_1 at /home/ahirzel/prj/dotfiles/scripts/bin/julia-1.3.0/lib/julia/sys.so (unknown line)
_jl_invoke at /buildworker/worker/package_linux64/build/src/gf.c:2135 [inlined]
jl_apply_generic at /buildworker/worker/package_linux64/build/src/gf.c:2305
jl_apply at /buildworker/worker/package_linux64/build/ui/../src/julia.h:1631 [inlined]
true_main at /buildworker/worker/package_linux64/build/ui/repl.c:96
main at /buildworker/worker/package_linux64/build/ui/repl.c:217
__libc_start_main at /usr/lib/libc.so.6 (unknown line)
_start at /home/ahirzel/prj/dotfiles/scripts/bin/julia-1.3.0/bin/julia (unknown line)
Allocations: 798245 (Pool: 798055; Big: 190); GC: 1
ERROR: Failed to precompile Cxx [a0b5b9ef-44b7-5148-a2d1-f6db19f3c3d2] to /home/ahirzel/.julia/compiled/v1.3/Cxx/ESGkI_zT4MM.ji.
Stacktrace:
 [1] error(::String) at ./error.jl:33
 [2] compilecache(::Base.PkgId, ::String) at ./loading.jl:1283
 [3] _require(::Base.PkgId) at ./loading.jl:1024
 [4] require(::Base.PkgId) at ./loading.jl:922
 [5] require(::Module, ::Symbol) at ./loading.jl:917

[TsurHerman]

It happens for me too on 1.3
Cxx seems to be broken