[previous] MISRA-C:2004  Rule  6.3:  (Advisory) [next] Typedefs that indicate size and signedness should be used in place of the basic numerical types.
The basic numerical types of signed and unsigned variants of char, int, short, long, and float, double should not be used, but specific-length typedefs should be used. Rule helps to clarify the size of the storage, but does not guarantee portability because of the asymmetric behaviour of integral promotion. See discussion of integral promotion - section 6.10. It is still important to understand the integer size of the implementation.

Programmers should be aware of the actual implementation of the typedefs under these definitions.

For example, the ISO (POSIX) typedefs as shown below are recommended and are used for all basic numerical and character types in this standard. For a 32-bit integer machine, these are as follows: 

typedef          char   char_t;
typedef signed   char   int8_t;
typedef signed   short  int16_t;
typedef signed   int    int32_t;
typedef signed   long   int64_t;
typedef unsigned char   uint8_t;
typedef unsigned short  uint16_t;
typedef unsigned int    uint32_t;
typedef unsigned long   uint64_t;
typedef          float  float32_t;
typedef          double float64_t;
typedef long     double float128_t;

typedefs are not considered necessary in the specification of bit-field types.

QAC messages that encompass this guideline:

5013 Use of basic type '%s'.


(c) The Motor Industry Research Association, 2004
QA C Source Code Analyser 8.1.2
MISRA-C:2004 Compliance Module 3.2
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