Code bloat

Code bloat is the production of code that is perceived as unnecessarily long, slow, or otherwise wasteful of resources. Code bloat can be caused by inadequacies in the language in which the code is written, the compiler used to compile it, or the programmer writing it. Thus, while code bloat generally refers to source code size (as produced by the programmer), it can be used to refer instead to the generated code size or even the binary file size.

Often, bloated code can result from a programmer who simply uses more lines of code than the optimal solution to a problem.

Some reasons for programmer derived code bloat are:

Some native implementations of the template system employed in C++ are examples of inadequacies in the compiler used to compile the language.

A native compiler implementing this feature can introduce versions of a method of a template class for every type it is used with. This in turns leads to compiled methods that may never be used, thus resulting in code bloat. More sophisticated compilers and linkers detect the superfluous copies and discard them, or avoid generating them at all, reducing the bloat. Thus template code can result in smaller binaries because a compiler is allowed to discard this kind of dead code.

Some examples of native compiler derived bloat include:

The following JavaScript algorithm has a large number of redundant variables, unnecessary logic and inefficient string concatenation.

The same logic can be stated more efficiently as follows:

The difference in code density between various computer languages is so great that often less memory is needed to hold both a program written in a "compact" language (such as a domain-specific programming language, Microsoft P-Code, or threaded code), plus an interpreter for that compact language (written in native code), than to hold that program written directly in native code.

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