Port better to FreeBSD’s dlfunc vs dlsym

This avoids warnings when converting between void * and
function pointers, which strict C11 does not allow.
* configure.ac (dlfunc): Check for existence.
* src/dynlib.c (dlfunc) [!HAVE_DLFUNC]: New macro.
(dynlib_func): New function.
* src/dynlib.h (dynlib_function_ptr, dynlib_func): New decls.
* src/emacs-module.c (Fmodule_load): Use dynlib_func, not
dynlib_sym, for function pointers.

1 files changed, 2 insertions, 0 deletions

diff --git a/src/dynlib.h b/src/dynlib.h
index 1282c4fd719..1c19b5db8ac 100644
--- a/src/dynlib.h
+++ b/src/dynlib.h
@@ -25,6 +25,8 @@ along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 typedef void *dynlib_handle_ptr;
 dynlib_handle_ptr dynlib_open (const char *path);
 void *dynlib_sym (dynlib_handle_ptr h, const char *sym);
+typedef struct dynlib_function_ptr_nonce *(*dynlib_function_ptr) (void);
+dynlib_function_ptr dynlib_func (dynlib_handle_ptr h, const char *sym);
 bool dynlib_addr (void *ptr, const char **path, const char **sym);
 const char *dynlib_error (void);
 int dynlib_close (dynlib_handle_ptr h);