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Preface Overview of the Compiler Getting Started with the Compiler Compiler Features Compiler Coding Practices Compiler Diagnostic Messages Using the Inline and Embedded Assemblers of the AR Compiler Command-line Options Language Extensions Preprocessor extensions #assert #include_next #unassert #warning C99 language features available in C90 // comments Subscripting struct Flexible array members C99 language features available in C++ and C90 Variadic macros long long restrict Hexadecimal floats Standard C language extensions Constant expressions Array and pointer extensions Block scope function declarations Dollar signs in identifiers Top-level declarations Benign redeclarations External entities Function prototypes Standard C++ language extensions ? operator Declaration of a class member friend Read/write constants Scalar type constants Specialization of nonmember function templates Type conversions Standard C and Standard C++ language extensions Address of a register variable Arguments to functions Anonymous classes, structures and unions Assembler labels Empty declaration Hexadecimal floating-point constants Incomplete enums Integral type extensions Label definitions Long float Nonstatic local variables Structure, union, enum, and bitfield extensions GNU extensions to the C and C++ languages Compiler-specific Features C and C++ Implementation Details What is Semihosting? Via File Syntax Summary Table of GNU Language Extensions Standard C Implementation Definition Standard C++ Implementation Definition C and C++ Compiler Implementation Limits

long long

8.12 long long

The ARM compiler supports 64-bit integer types through the type specifiers long long and unsigned long long.

They behave analogously to long and unsigned long with respect to the usual arithmetic conversions. __int64 is a synonym for long long.
Integer constants can have:
  • An ll suffix to force the type of the constant to long long, if it fits, or to unsigned long long if it does not fit
  • A ull or llu suffix to force the type of the constant to unsigned long long.
Format specifiers for printf() and scanf() can include ll to specify that the following conversion applies to a long long argument, as in %lld or %llu.
Also, a plain integer constant is of type long long or unsigned long long if its value is large enough. There is a warning message from the compiler indicating the change. For example, in strict 1990 ISO Standard C 2147483648 has type unsigned long. In ARM C and C++ it has the type long long. One consequence of this is the value of an expression such as:
2147483648 > –1 
This expression evaluates to 0 in strict C and C++, and to 1 in ARM C and C++.
The long long types are accommodated in the usual arithmetic conversions.
Related reference
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