> /Applications/eclipse C++/Includes/libgcrypt-1.5.0/src/gcrypt.h:1336: warning: 'gcry_ac_io_mode_t' is deprecated
For all of these, you need to read the project documentation to find out what new thing to use in it's place.

> ../src/aesTest.c:100: warning: format '%d' expects type 'int', but argument 2 has type 'size_t'
In newer C versions, use "%zd" as the printf format for printing a size_t

> Undefined symbols for architecture x86_64:
> "_gcry_cipher_get_algo_keylen", referenced from:
I saw a lot of -L options (uppercase), but no -l (lowercase) option.
If the library is called libfoo.a, then you need to say -lfoo on that command line / linker settings.