programming-for-dummies

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Choosing a Compiler
• By creating front-ends for different languages, programmers can
make the GCC compiler compile more programming languages.
✦ The back-end of the compiler finishes translating the intermediate code
into actual machine code.
Evaluating the technical features of a compiler
After you choose a particular programming language and pick which operating
systems you want your programs to run on, your list of compiler choices
is likely narrowed down to one or two choices. Given two compilers that
both meet your needs, you can pick the “best” compiler by examining their
technical features.
The technical features of a compiler are meaningless if
✦ The compiler stops being developed and supported.
✦ The compiler can’t run under the operating system or processor you
need in the future.
✦ A particular technical feature is something you don’t need or care about.
Supported language standards
No two compilers are alike, even those that compile the same programming
language, such as C++. The problem is that every programming language has
an official “standard,” but the standard for most programming languages is
usually far behind what people in the real world are actually using. (By the time
an official standards committee agrees on the features of a given programming
language, programmers have already created new features that eventually
become standards in future versions of that language.)
As a result, most compilers support a given language standard plus additional
features that programmers have developed. Therefore, every compiler
actually works with a different dialect of a programming language. So C++
programs that run under the Microsoft Visual C++ compiler may or may not
run the same when compiled under the GCC compiler, even though both
compilers claim to support the “standard” C++ programming language.
Language standards are nice but generally useless when comparing compilers.
What’s more important is whether a particular compiler offers the specific
features you need or want, regardless of whatever particular standard it may
follow.
Code generation and optimization
Every compiler converts source code into machine language, but some compilers
can translate source code into more efficient machine language commands