Re: [Libguestfs] Patchable build problems on OS X 10.10
On Sat, Feb 07, 2015 at 02:51:53AM +0000, Margaret Lewicka wrote:
On 6 February 2015 at 10:03, Richard W.M. Jones
<rjones(a)redhat.com> wrote:
[...]
> Linux doesn't have getprogname. One way around this is to add
> getprogname to the list of functions in configure.ac AC_CHECK_FUNCS.
> That will cause a macro to be defined which you can use like this:
>
> #if HAVE_DECL_PROGRAM_INVOCATION_SHORT_NAME == 1
> # define program_name program_invocation_short_name
> #elif HAVE_GETPROGNAME
> # define program_name getprogname()
> #else
> # define program_name "libguestfs"
> #endif
Unfortunately that still doesn't help the issue with gnulib, since it
expects char *program_name to be set on non-Linux platforms.
I believe I understand the problem now. The gnulib 'error' module
uses program_name. As you say above on some platforms -- but not
Linux / glibc -- it references it as:
extern char *program_name;
This means when you compile libguestfs on non-glibc (eg. Mac OS X)
gnulib requires program_name as an external reference, which we don't
provide.
Complicating this is that libguestfs defines a macro called
program_name, which prevents us from easily defining the required
external symbol.
Anyway, I have changed libguestfs to use the macro
guestfs___program_name which cannot conflict with anything:
https://github.com/libguestfs/libguestfs/commit/5cafedaa45d5993c54bf18274...
I'm not quite sure who/what gnulib is expecting to define
program_name. While it would be possible to add the following to
libguestfs somewhere (in a .c file):
#if /*compiling for Mac OS X*/
char *program_name = "libguestfs";
#endif
that could be a mistake if either Darwin itself or the main program
(not a library like libguestfs) is expected to define this symbol. So
over to you to experiment!
Thanks,
Rich.
--
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