In working on my latest proposed patch, I also noticed an outdated error message in zic.c which referred to the FROM field of a Link line. We had updated these field names in comments and documentation in release 2014g to be more descriptive and readily understandable like the parameters of 'ln':
The attached proposed patch further updates the zic.c code to more consistently use these new names throughout. This mostly affects the naming of parameters and locals, but a few macros and struct fields are also updated for consistency.