<![CDATA[MISRA Discussion Forums - 6.2 Lexical conventions (C++)]]> https://forum.misra.org.uk/ Thu, 05 Nov 2026 20:03:05 +0000 MyBB <![CDATA[2-10-2 "block scope" for classes and namespaces]]> https://forum.misra.org.uk/showthread.php?tid=1470 Thu, 14 Feb 2019 11:11:21 +0000 abgs]]> https://forum.misra.org.uk/showthread.php?tid=1470
Code:
int i;
namespace n { int i; } // A
namespace { int i; } // B
class c { int i; }; // C

class c2 { int k; void f() { int k; } }; // D

class base { int z; };
class derived : public base { int z; }; // E
]]>
Code:
int i;
namespace n { int i; } // A
namespace { int i; } // B
class c { int i; }; // C

class c2 { int k; void f() { int k; } }; // D

class base { int z; };
class derived : public base { int z; }; // E
]]> <![CDATA[Difference between 2-10-2 and MISRA C-2012 Rule 5.3]]> https://forum.misra.org.uk/showthread.php?tid=1455 Wed, 19 Sep 2018 06:04:32 +0000 cxlin]]> https://forum.misra.org.uk/showthread.php?tid=1455
MISRA C-2012 Rule 5.3 (which is of the same title as 2-10-2) has this additional amplification about an identifier declared in an inner scope shall be distinct from *any* id declared in an outer scope.

So the following code shall be a violation for 5.3 although the inner "i" is not hiding the outer "i" (still confusing though).

Code:
void f() {
    {
        int i; // Non-compliant
    }
    int i;
}

Since 2-10-2 does not have this amplification, could you kindly help to advise whether this is also a violation for 2-10-2 or not?]]>
MISRA C-2012 Rule 5.3 (which is of the same title as 2-10-2) has this additional amplification about an identifier declared in an inner scope shall be distinct from *any* id declared in an outer scope.

So the following code shall be a violation for 5.3 although the inner "i" is not hiding the outer "i" (still confusing though).

Code:
void f() {
    {
        int i; // Non-compliant
    }
    int i;
}

Since 2-10-2 does not have this amplification, could you kindly help to advise whether this is also a violation for 2-10-2 or not?]]> <![CDATA[Rule 2-5-1]]> https://forum.misra.org.uk/showthread.php?tid=1374 Sun, 01 Oct 2017 01:31:16 +0000 ogawa.kiyoshi]]> https://forum.misra.org.uk/showthread.php?tid=1374 The usage of digraphs are only system constraints.
Digraph are just an alternative method for a systems that can not input '{','}','[',']'.
Therefore, there is no point in leaving a digraph in the final source file.
Even if anyone use a system that requires digraphs, it is better to replace in the final source file from digraph(alternative token) to primary token.]]> The usage of digraphs are only system constraints.
Digraph are just an alternative method for a systems that can not input '{','}','[',']'.
Therefore, there is no point in leaving a digraph in the final source file.
Even if anyone use a system that requires digraphs, it is better to replace in the final source file from digraph(alternative token) to primary token.]]> <![CDATA[2-10-1 No "overlapping visibility" restriction?]]> https://forum.misra.org.uk/showthread.php?tid=1326 Thu, 16 Mar 2017 14:14:38 +0000 grunwald]]> https://forum.misra.org.uk/showthread.php?tid=1326 C++ Rule 2-10-1: "Different identifiers shall be typographically unambiguous."

Does this mean the C++ rule applies even to identifiers in different scopes?

Code:
void f1() { int i; }
void f2() { int I; } // 2-10-1 violation due to only differing in case?

Also, does the C++ rule forbid naming a variables after their class name?

Code:
class MyClass { };
MyClass myClass;  // 2-10-1 violation?
]]> C++ Rule 2-10-1: "Different identifiers shall be typographically unambiguous."

Does this mean the C++ rule applies even to identifiers in different scopes?

Code:
void f1() { int i; }
void f2() { int I; } // 2-10-1 violation due to only differing in case?

Also, does the C++ rule forbid naming a variables after their class name?

Code:
class MyClass { };
MyClass myClass;  // 2-10-1 violation?
]]> <![CDATA[Did '\000' and 000 comply with Rule 2-13-2]]> https://forum.misra.org.uk/showthread.php?tid=1318 Tue, 28 Feb 2017 06:09:09 +0000 longfem]]> https://forum.misra.org.uk/showthread.php?tid=1318 Rule 2-10-3 said that Octal constants (other than zero) and octal escape sequences (other than “\0”) shall not be used.

From the description we know that '\0' and 0 comply with the rule.
How about '\00', '\000' , 00 and 000 ?

Thanks,
Longfem]]> Rule 2-10-3 said that Octal constants (other than zero) and octal escape sequences (other than “\0”) shall not be used.

From the description we know that '\0' and 0 comply with the rule.
How about '\00', '\000' , 00 and 000 ?

Thanks,
Longfem]]> <![CDATA[Rule 2-10-5 is totaly ambiguous]]> https://forum.misra.org.uk/showthread.php?tid=1246 Sun, 15 May 2016 05:36:38 +0000 udi]]> https://forum.misra.org.uk/showthread.php?tid=1246
I think this rule should be rephrased (or maybe split) for clarity, and giving some more examples.
Problems are:
1. As already mentioned - function overloading.

2. It is not clear whether static variables inside function are violating this rule:
void f1() { static int nFoo; }
void f2() { static int nFoo; }
I think it does not violate (also based on my exmaples from MISRA C-2012 Rule 5.9) but my static analysis tool, thinks it does.

3. Do static class members violate this rule?
class C1 { public: static int nNumOfItems; }
class C2 { public: static int nNumOfItems; }
I think it does not.

To my understanding, this rule comes to cover 2 cases (which should be properly explained in the rationale):
1. Hiding of identifier in an internal scope
2. Conusion of 2 global static identifiers with the same name (whose scope is actualy indipendantly limited to each .cpp file)

Thanks,
Udi.]]>
I think this rule should be rephrased (or maybe split) for clarity, and giving some more examples.
Problems are:
1. As already mentioned - function overloading.

2. It is not clear whether static variables inside function are violating this rule:
void f1() { static int nFoo; }
void f2() { static int nFoo; }
I think it does not violate (also based on my exmaples from MISRA C-2012 Rule 5.9) but my static analysis tool, thinks it does.

3. Do static class members violate this rule?
class C1 { public: static int nNumOfItems; }
class C2 { public: static int nNumOfItems; }
I think it does not.

To my understanding, this rule comes to cover 2 cases (which should be properly explained in the rationale):
1. Hiding of identifier in an internal scope
2. Conusion of 2 global static identifiers with the same name (whose scope is actualy indipendantly limited to each .cpp file)

Thanks,
Udi.]]> <![CDATA[Rule 2-10-6]]> https://forum.misra.org.uk/showthread.php?tid=1223 Tue, 26 Jan 2016 09:04:38 +0000 Mats Fors]]> https://forum.misra.org.uk/showthread.php?tid=1223
typedef struct vector {...} vector;

The two vector identifiers are both referring to the same type.]]>
typedef struct vector {...} vector;

The two vector identifiers are both referring to the same type.]]> <![CDATA[Rule 2-10-5 and function overloading]]> https://forum.misra.org.uk/showthread.php?tid=560 Wed, 23 Jul 2008 16:26:01 +0000 pkruk]]> https://forum.misra.org.uk/showthread.php?tid=560
does rule 2-10-5 disallows function overloading? What is the definition of "identifier reuse"?
For example:
Code:
class C{};
void foo(int);
void foo(C);      // Not compliant?
void foo(int, C); // Not compliant?
]]>
does rule 2-10-5 disallows function overloading? What is the definition of "identifier reuse"?
For example:
Code:
class C{};
void foo(int);
void foo(C);      // Not compliant?
void foo(int, C); // Not compliant?
]]>