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MISRA C:2012 Rule-10.4: (Required) |
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Amplification:
This rule applies to operators that are described in usual arithmetic conversions [C90 Section 6.2.1.5, C99 Section 6.3.1.8]. This includes all the binary operators, excluding the shift, logical &&, logical || and comma operators. In addition, the 2nd and 3rd operands of the ternary operator are covered by this rule.
Note that the increment and decrement operators are not covered by this rule.
Exception:
The following are permitted to allow a common form of character manipulation to be used:
Example Code:
#pragma PRQA_MESSAGES_OFF 2984,2985,3112
#include "misra.h"
#include "m3cmex.h"
extern int16_t rule_1004_integer_float( void )
{
s32a + f32a; /* 1800 */
s32a - f32a; /* 1800 */
s32a * f32a; /* 1800 */
s32a / f32a; /* 1800 */
s32a % f32a; /* 0496 */
s32a & f32a; /* 0496 */
s32a | f32a; /* 0496 */
s32a ^ f32a; /* 0496 */
s32a < f32a; /* 1802 */
s32a <= f32a; /* 1802 */
s32a >= f32a; /* 1802 */
s32a > f32a; /* 1802 */
s32a == f32a; /* 1803 */
s32a != f32a; /* 1803 */
(u32a > u32b) ? s32a : f32a; /* 1804 */
return 0;
}
Example Code:
#pragma PRQA_MESSAGES_OFF 3112
#include "misra.h"
#include "m3cmex.h"
extern int16_t rule_1004_signed_unsigned( void )
{
/****************************************
NON-CONSTANT SIGNED converted to UNSIGNED
*****************************************/
s32a + u32a; /* 1820 */
s32a - u32a; /* 1820 */
s32a * u32a; /* 1820 */
s32a / u32a; /* 1820 */
s32a % u32a; /* 1820 */
s32a & u32a; /* 1821 4532 */
s32a | u32a; /* 1821 4532 */
s32a ^ u32a; /* 1821 4532 */
s32a < u32a; /* 1822 */
s32a <= u32a; /* 1822 */
s32a >= u32a; /* 1822 */
s32a > u32a; /* 1822 */
s32a == u32a; /* 1823 */
s32a != u32a; /* 1823 */
(u32a > u32b) ? s32a : u32a; /* 1824 */
/*********************************************
CONSTANT NEGATIVE SIGNED converted to UNSIGNED
***********************************************/
-123 + u32a; /* 1830 2890 */
-123 - u32a; /* 1830 2890 */
-123 * u32a; /* 1830 2890 */
-123 / u32a; /* 1830 2890 */
-123 % u32a; /* 1830 2890 */
-123 & u32a; /* 1831 2890 4532 */
-123 | u32a; /* 1831 2890 4532 */
-123 ^ u32a; /* 1831 2890 4532 */
-123 < u32a; /* 1832 2890 */
-123 <= u32a; /* 1832 2890 */
-123 >= u32a; /* 1832 2890 */
-123 > u32a; /* 1832 2890 */
-123 == u32a; /* 1833 2890 */
-123 != u32a; /* 1833 2890 */
(u32a > u32b) ? -123 : u32a; /* 1834 2890 */
/*************************************************
CONSTANT NON-NEGATIVE SIGNED converted to UNSIGNED
**************************************************/
1234 + u32a; /* 1840 */
1234 - u32a; /* 1840 */
1234 * u32a; /* 1840 */
1234 / u32a; /* 1840 */
1234 % u32a; /* 1840 */
1234 & u32a; /* 1841 4542 */
1234 | u32a; /* 1841 4542 */
1234 ^ u32a; /* 1841 4542 */
1234 < u32a; /* 1842 */
1234 <= u32a; /* 1842 */
1234 >= u32a; /* 1842 */
1234 > u32a; /* 1842 */
1234 == u32a; /* 1843 */
1234 != u32a; /* 1843 */
(u32a > u32b) ? 1234 : u32a; /* 1844 */
/***************************
UNSIGNED converted to SIGNED
***************************/
s32a + u16a; /* 1850 */
s32a - u16a; /* 1850 */
s32a * u16a; /* 1850 */
s32a / u16a; /* 1850 */
s32a % u16a; /* 1850 */
s32a & u16a; /* 1851 4532 */
s32a | u16a; /* 1851 4532 */
s32a ^ u16a; /* 1851 4532 */
s32a < u16a; /* 1852 */
s32a <= u16a; /* 1852 */
s32a >= u16a; /* 1852 */
s32a > u16a; /* 1852 */
s32a == u16a; /* 1853 */
s32a != u16a; /* 1853 */
(u32a > u32b) ? s32a : u16a; /* 1854 */
/********************************************
BOTH undergo INTEGRAL PROMOTION to signed int
*********************************************/
s8a + u8a; /* 1860 */
s8a - u8a; /* 1860 */
s8a * u8a; /* 1860 */
s8a / u8a; /* 1860 */
s8a % u8a; /* 1860 */
s8a & u8a; /* 1861 4532 */
s8a | u8a; /* 1861 4532 */
s8a ^ u8a; /* 1861 4532 */
s8a < u8a; /* 1862 */
s8a <= u8a; /* 1862 */
s8a >= u8a; /* 1862 */
s8a > u8a; /* 1862 */
s8a == u8a; /* 1863 */
s8a != u8a; /* 1863 */
(u32a > u32b) ? s8a : u8a; /* 1864 */
return 0;
}
Example Code:
#pragma PRQA_MESSAGES_OFF 3112
#include "misra.h"
#include "m3cmex.h"
extern int16_t rule_1004_compare( void )
{
/***************************
RELATIONAL OPERATIONS
***************************/
pca > n1a; /* 1880 */
pca > s16a; /* 1880 */
pca > u16a; /* 1880 */
pca > f32a; /* 1880 */
n1a > pca; /* 1880 */
n1a > n2a; /* 1880 */
n1a > s16a; /* 1880 */
n1a > u16a; /* 1880 */
n1a > f32a; /* 1802 */
s8a > pca; /* 1880 */
s8a > n2a; /* 1880 */
s8a > f32a; /* 1802 */
u8a > pca; /* 1880 */
u8a > n2a; /* 1880 */
u8a > f32a; /* 1802 */
f32a > pca; /* 1880 */
f32a > n2a; /* 1802 */
f32a > s16a; /* 1802 */
f32a > u16a; /* 1802 */
/***************************
EQUALITY OPERATIONS
***************************/
pca == n1a; /* 1881 */
pca == s16a; /* 1881 */
pca == u16a; /* 1881 */
pca == f32a; /* 1881 */
n1a == pca; /* 1881 */
n1a == n2a; /* 1881 */
n1a == s16a; /* 1881 */
n1a == u16a; /* 1881 */
n1a == f32a; /* 1803 */
s8a == pca; /* 1881 */
s8a == n2a; /* 1881 */
s8a == f32a; /* 1803 */
u8a == pca; /* 1881 */
u8a == n2a; /* 1881 */
u8a == f32a; /* 1803 */
f32a == pca; /* 1881 */
f32a == n2a; /* 1803 */
f32a == s16a; /* 1803 */
f32a == u16a; /* 1803 */
/***************************
CONDITIONAL OPERATIONS
***************************/
(u32a > u32b) ? pca : n1a; /* 1882 */
(u32a > u32b) ? pca : s16a; /* 1882 */
(u32a > u32b) ? pca : u16a; /* 1882 */
(u32a > u32b) ? pca : f32a; /* 1882 */
(u32a > u32b) ? n1a : pca; /* 1882 */
(u32a > u32b) ? n1a : n2a; /* 1882 */
(u32a > u32b) ? n1a : s16a; /* 1882 */
(u32a > u32b) ? n1a : u16a; /* 1882 */
(u32a > u32b) ? n1a : f32a; /* 1804 */
(u32a > u32b) ? s8a : pca; /* 1882 */
(u32a > u32b) ? s8a : n2a; /* 1882 */
(u32a > u32b) ? s8a : f32a; /* 1804 */
(u32a > u32b) ? u8a : pca; /* 1882 */
(u32a > u32b) ? u8a : n2a; /* 1882 */
(u32a > u32b) ? u8a : f32a; /* 1804 */
(u32a > u32b) ? f32a : pca; /* 1882 */
(u32a > u32b) ? f32a : n2a; /* 1804 */
(u32a > u32b) ? f32a : s16a; /* 1804 */
(u32a > u32b) ? f32a : u16a; /* 1804 */
return 0;
}
QAC messages that encompass this guideline:
| 1800 | The %1s operand (essential type: '%2s') will be implicitly converted to a floating type, '%3s', in this arithmetic operation. |
| 1802 | The %1s operand (essential type: '%2s') will be implicitly converted to a floating type, '%3s', in this relational operation. |
| 1803 | The %1s operand (essential type: '%2s') will be implicitly converted to a floating type, '%3s', in this equality operation. |
| 1804 | The %1s operand (essential type: '%2s') will be implicitly converted to a floating type, '%3s', in this conditional operation. |
| 1820 | The %1s operand is non-constant and 'essentially signed' (%2s) but will be implicitly converted to an unsigned type (%3s) in this arithmetic operation. |
| 1821 | The %1s operand is non-constant and 'essentially signed' (%2s) but will be implicitly converted to an unsigned type (%3s) in this bitwise operation. |
| 1822 | The %1s operand is non-constant and 'essentially signed' (%2s) but will be implicitly converted to an unsigned type (%3s) in this relational operation. |
| 1823 | The %1s operand is non-constant and 'essentially signed' (%2s) but will be implicitly converted to an unsigned type (%3s) in this equality operation. |
| 1824 | The %1s operand is non-constant and 'essentially signed' (%2s) but will be implicitly converted to an unsigned type (%3s) in this conditional operation. |
| 1830 | The %1s operand is constant, 'essentially signed' (%2s) and negative but will be implicitly converted to an unsigned type (%3s) in this arithmetic operation. |
| 1831 | The %1s operand is constant, 'essentially signed' (%2s) and negative but will be implicitly converted to an unsigned type (%3s) in this bitwise operation. |
| 1832 | The %1s operand is constant, 'essentially signed' (%2s) and negative but will be implicitly converted to an unsigned type (%3s) in this relational operation. |
| 1833 | The %1s operand is constant, 'essentially signed' (%2s) and negative but will be implicitly converted to an unsigned type (%3s) in this equality operation. |
| 1834 | The %1s operand is constant, 'essentially signed' (%2s) and negative but will be implicitly converted to an unsigned type (%3s) in this conditional operation. |
| 1840 | The %1s operand is constant, 'essentially signed' (%2s) and non-negative but will be implicitly converted to an unsigned type (%3s) in this arithmetic operation. |
| 1841 | The %1s operand is constant, 'essentially signed' (%2s) and non-negative but will be implicitly converted to an unsigned type (%3s) in this bitwise operation. |
| 1842 | The %1s operand is constant, 'essentially signed' (%2s) and non-negative but will be implicitly converted to an unsigned type (%3s) in this relational operation. |
| 1843 | The %1s operand is constant, 'essentially signed' (%2s) and non-negative but will be implicitly converted to an unsigned type (%3s) in this equality operation. |
| 1844 | The %1s operand is constant, 'essentially signed' (%2s) and non-negative but will be implicitly converted to an unsigned type (%3s) in this conditional operation. |
| 1850 | The %1s operand is 'essentially unsigned' (%2s) but will be implicitly converted to a signed type (%3s) in this arithmetic operation. |
| 1851 | The %1s operand is 'essentially unsigned' (%2s) but will be implicitly converted to a signed type (%3s) in this bitwise operation. |
| 1852 | The %1s operand is 'essentially unsigned' (%2s) but will be implicitly converted to a signed type (%3s) in this relational operation. |
| 1853 | The %1s operand is 'essentially unsigned' (%2s) but will be implicitly converted to a signed type (%3s) in this equality operation. |
| 1854 | The %1s operand is 'essentially unsigned' (%2s) but will be implicitly converted to a signed type (%3s) in this conditional operation. |
| 1860 | The operands of this arithmetic operator are of different 'essential signedness' but will generate a result of type 'signed int'. |
| 1861 | The operands of this bitwise operator are of different 'essential signedness' but will generate a result of type 'signed int'. |
| 1862 | The operands of this relational operator are of different 'essential signedness' but will both be promoted to 'signed int' for comparison. |
| 1863 | The operands of this equality operator are of different 'essential signedness' but will both be promoted to 'signed int' for comparison. |
| 1864 | The 2nd and 3rd operands of this conditional operator are of different 'essential signedness'. The result will be in the promoted type 'signed int'. |
| 1880 | The operands of this relational operator are expressions of different 'essential type' categories (%1s and %2s). |
| 1881 | The operands of this equality operator are expressions of different 'essential type' categories (%1s and %2s). |
| 1882 | The 2nd and 3rd operands of this conditional operator are expressions of different 'essential type' categories (%1s and %2s). |
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(c) The Motor Industry Research Association, 2012
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QA C Source Code Analyser 8.1.2
MISRA C:2012 Compliance Module 1.0 © 2013 Programming Research www.programmingresearch.com |
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