[Patch] Configure broken for Solaris 2.6 (PR#12014)

[David Collier-Brown]

AHA!  Success!

If I don't include confdefs.h in the conftest.c from
line 8748, I don't have a crash in the midst of reading
/usr/include/sys/types.h, and the compile succeeds. If so,
I can then find that I have statvfs() and away we go.

I'm not entirely sure what the 
--
#define off_t long
--
are in there for, but it definitely causes an interesting
clash at line 89 of sys/types.h, by causing the line
to become:
--
# 89
typedef longlong_t       long ;         /* offsets within files */
--

Cool!  It normally would say 
--
typedef longlong_t      off_t;  	/* offsets within files */
--
but the #define make it suffer a sea-change, rich and strange (;-))

Can confdefs.h avoid #defining types?  It sort of pollutes the
configuration tests, although it may be necessary...

--dave (autoconf considered harmful: David Tilbrook (:-)) c-b