Issue with libunwind on OSX 10.8.4

[c0g]

I am trying to build julia on OSX 10.8.4, revision afb71a5.

There seems to be something broken in the latest version of Julia on OSX. I believe the bug is in libunwind, due to it referencing ucontext.h:

make cleanall
make
...snip...
/bin/sh ../libtool   --mode=install /usr/local/bin/ginstall -c dnsimp '/Users/tom/Source/julia/usr/bin'
libtool: install: /usr/local/bin/ginstall -c .libs/dnsimp /Users/tom/Source/julia/usr/bin/dnsimp
CC src/jltypes.o
In file included from jltypes.c:13:
In file included from ./julia.h:1228:
In file included from /Users/tom/Source/julia/usr/include/libunwind.h:23:
In file included from /Users/tom/Source/julia/usr/include/libunwind-x86_64.h:36:
/usr/include/ucontext.h:43:2: error: The deprecated ucontext routines require _XOPEN_SOURCE to be defined
#error The deprecated ucontext routines require _XOPEN_SOURCE to be defined
^
1 error generated.
make[2]: *** [jltypes.o] Error 1
make[1]: *** [julia-release] Error 2
make: *** [release] Error 2

Modifying usr/include/libunwind-x86-64 to define _XOPEN_SOURCE and point to sys/ucontext.h (vague suggestion from googling) changes the error. I tested with all three combinations of these (both on, _XOPEN on, sys/ on) and got the same error:

make cleanall
make
...snip...
CC src/codegen.o
CC src/interpreter.o
CC src/alloc.o
CC src/dlload.o
CC src/sys.o
CC src/init.o
CC src/task.o
CC src/array.o
CC src/dump.o
CC src/toplevel.o
CC src/jl_uv.o
CC src/jlapi.o
CC src/profile.o
CC src/gc.o
LINK usr/lib/libjulia-release.dylib
Undefined symbols for architecture x86_64:
"__ULx86_64_get_reg", referenced from:
_rec_backtrace in task.o
_rec_backtrace_ctx in task.o
_jl_backtrace_from_here in task.o
_gdbbacktrace in task.o
_jl_throw in task.o
"__ULx86_64_init_local", referenced from:
_rec_backtrace in task.o
_rec_backtrace_ctx in task.o
_jl_backtrace_from_here in task.o
_gdbbacktrace in task.o
_jl_throw in task.o
"__ULx86_64_step", referenced from:
_rec_backtrace in task.o
_rec_backtrace_ctx in task.o
_jl_backtrace_from_here in task.o
_gdbbacktrace in task.o
_jl_throw in task.o
"__Ux86_64_getcontext", referenced from:
_rec_backtrace in task.o
_jl_backtrace_from_here in task.o
_gdbbacktrace in task.o
_jl_throw in task.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[2]: *** [/Users/tom/Source/julia/usr/lib/libjulia-release.dylib] Error 1
make[1]: *** [julia-release] Error 2
make: *** [release] Error 2

This might be a problem in Julia, or it might be in unwind, or on my machine. Or it might be something else entirely!

[c0g]

I must have broken my Julia tree somewhere. Deleting it, re-cloning and rebuilding worked perfectly.