Examples
One modern example of dependency hell on Microsoft Windows and Mac OS X is the Gecko Runtime Engine, or GRE, used by Mozilla projects. Each product released from the Mozilla foundation includes its own version of the complete Gecko Runtime Engine, due to the volatile nature of the programming interfaces used. Thus, if a user installs Thunderbird, Firefox, and Sunbird, there will be three copies of GRE on the machine. These may or may not be compatible, depending on when the GRE source tree was forked. Some external projects like Epiphany depend on specific versions of the Mozilla Suite to use GRE, and break if a different version is installed, while others such as Nvu bring their own copy of GRE. The duplication of the GRE is actually a work-around to the core problem of dependency hell.
By statically linking Gecko, the Mozilla developers avoid potential dependency hell for their binary packages, at the cost of increased disk and memory usage. Hard disk space comes quite cheap these days, therefore increased disk usage in itself is less of a problem than it once was, but the amount of extra non-shareable memory used is still considerable. (Also note that limitations on backing store size are returning with the use of solid-state drives for portable computers.) Tools that are statically linked, such as bash or make, will never complain about a missing shared object when the C library (glibc) is upgraded. Both approaches have advantages and disadvantages.
Further, many modern Linux distributions avoid this particular dependency problem by compiling Firefox, Thunderbird, etc. as merely a front-end to the XULRunner package, thereby necessitating only one copy of the runtime being installed. Another solution that stops dependency hell is made possible because a distribution's software repository can keep all of the user's software in sync.
Read more about this topic: Dependency Hell
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