As discussed here:

   http://www.redhat.com/archives/libvir-list/2012-February/msg00612.html

libvirt 0.9.10 final does not build on MacOS/X, while (according to
the list, I first started using with 0.9.10) 0.9.10-rc1 did build
correctly.

The following patch seems to fix it.  I believe virFileWrapperFdFlags
was accidentally declared as a global variable instead of as a type,
one way or another:

  --- a/src/util/virfile.h	Thu Feb 16 01:56:57 2012 -0800
  +++ b/src/util/virfile.h	Sat Feb 18 20:35:03 2012 -0800
  @@ -58,10 +58,10 @@
  
   int virFileDirectFdFlag(void);
   
  -enum {
  +enum virFileWrapperFdFlags {
       VIR_FILE_WRAPPER_BYPASS_CACHE   = (1 << 0),
       VIR_FILE_WRAPPER_NON_BLOCKING   = (1 << 1),
  -} virFileWrapperFdFlags;
  +};
  
   virFileWrapperFdPtr virFileWrapperFdNew(int *fd,
                                           const char *name,