Search results
Results from the WOW.Com Content Network
In computer programming, unspecified behavior is behavior that may vary on different implementations of a programming language. [clarification needed] A program can be said to contain unspecified behavior when its source code may produce an executable that exhibits different behavior when compiled on a different compiler, or on the same compiler with different settings, or indeed in different ...
For example, if the type of a variable as specified in the source code is narrower than the native register width (such as int on a 64-bit machine, a common scenario), then the compiler can safely use a signed 64-bit integer for the variable in the machine code it produces, without changing the defined behavior of the code. If a program ...
Typically compiler directives define or "undefine" certain variables; other directives test these variables and modify compilation accordingly. For example, not using an actual language, the compiler may be set to define "Macintosh" and undefine "PC", and the code may contain:
Programming languages can have multiple implementations. Different implementations can be written in different languages and can use different methods to compile or interpret code. For example, implementations of Python include: [9] CPython, the reference implementation of Python; IronPython, an implementation targeting the .NET Framework ...
A built-in function, or builtin function, or intrinsic function, is a function for which the compiler generates code at compile time or provides in a way other than for other functions. [23] A built-in function does not need to be defined like other functions since it is built in to the programming language. [24]
Whereas the former example relied only on guarantees made by the C programming language about structure layout and pointer convertibility, the latter example relies on assumptions about a particular system's hardware. Some situations, such as time-critical code that the compiler otherwise fails to optimize, may require
For example, coding: UTF-8 indicates that the file is encoded via the UTF-8 character encoding. In C#, compiler directives are called pre-processing directives. There are a number of different compiler directives including #pragma, which is specifically used to control compiler warnings and debugger checksums. [5] [6]
A snippet of Python code with keywords highlighted in bold yellow font. The syntax of the Python programming language is the set of rules that defines how a Python program will be written and interpreted (by both the runtime system and by human readers). The Python language has many similarities to Perl, C, and Java. However, there are some ...