[m-users.] Problem compiling 14.01.1 on 64 bit Cygwin

[Peter Chapin]

Hello!

I previously tried to compile 14.01 on 64 bit Cygwin and encountered an 
error in the Boehm GC related to 64 bit targets. I posted to this list and 
was told there was an issue building Boehm for 64 bits but that there was 
an upstream fix that would make its way into Mercury at the next release.

The release notes for 14.01.1 include

* A problem that caused compilation of the Boehm GC to fail on 64-bit 
openSUSE 13.1 systems has been fixed.  (Github issue #14)

Optimistically I attempted to build Mercury 14.01.1 on 64 bit Cygwin again 
but encountered what looks like the same problem. In particular:

/usr/local/src/mercury-srcdist-14.01.1/boehm_gc/../scripts/mgnuc --grade 
hlc.gc.pregen --no-ansi --no-check --no-mercury-stdlib-dir -I./include 
-I./libatomic_ops-install/include -DNO_EXECUTE_PERMISSION -DLARGE_CONFIG 
-DNO_DEBUGGING   -c -o alloc.o alloc.c

In file included from ./include/private/gc_priv.h:94:0,
                  from alloc.c:18:
./include/private/gcconfig.h:1096:7: error: #error This should be handled 
as X86_64
  #     error This should be handled as X86_64
        ^
./include/private/gcconfig.h:2416:3: error: #error --> undefined ALIGNMENT
  # error --> undefined ALIGNMENT
    ^
<builtin>: recipe for target 'alloc.o' failed


So I guess 64 bit Cygwin is not supported yet? Or am I missing a 
configuration option that I should be used (I ran configure with no 
arguments).

Thanks!
Peter