mozilla/webvtt — pull request #283 by caitp (2013-03-21 16:50:17+00:00)
Title: [warning] parser.c (lines 881, 884, 887, 890, 893) sign-compare warning

The macro called on this line compares unsigned (have_ws) to signed (last_column). There is no reason 'have_ws' can't be unsigned, as it defaults to 0 and is set to a column where a whitespace occurs (never < 0 ).