The build environment seems to sneak into the artifacts in many ways. Check out some of the listings from the "Upstream Patches" section of the linked page.. So

The build environment seems to sneak into the artifacts in many ways. Check out some of the listings from the "Upstream Patches" section of the linked page.. Some of the most common reasons seem to be: timestamps, non-deterministic file listings, debug information containing build path data, permissions bits on artifact files,etc.