Основы программирования в Linux

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unqualified storage: array[4].data = "alex"

debug0.с:14:22: Old style function declaration

 Function definition is in old style syntax. Standard prototype syntax is

 preferred. (Use -oldstyle to inhibit warning)

debug0.с: (in function sort)

debug0.c:20:31: Variable s used before definition

 An rvalue is used that may not be initialized to a value on some execution

 path. (Use -usedef to inhibit warning)

debug0.с:20:23: Left operand of & is not unsigned value (boolean):

i < n & s != 0

 An operand to a bitwise operator is not an unsigned values. This may have

 unexpected results depending on the signed representations. (Use

 -bitwisesigned to inhibit warning).

debug0.c:20:23: Test expression for for not boolean, type unsigned int:

i < n & s != 0

 Test expression type is not boolean or int. (Use -predboolint to inhibit

 warning);

debug0.с:25:41: Undocumented modification of a[]: a[j] = a[j + 1]

 An externally-visible object is modified by a function with no /*@modifies@*/

 comment. The /*@modifies ... @*/ control comment can be used to give a

 modifies list for an unspecified function. (Use -modnomods to inhibit

 warning)

debug0.c:26:41: Undocumented modification of a[]: a[j + 1] = t

debug0.c:20:23: Operands of & are non-integer (boolean) (in post loop test):

i < n & s != 0

 A primitive operation does not type check strictly. (Use -strictops to

 inhibit warning)

debug0.с:32:14: Path with no return in function declared to return int

 There is a path through a function declared to return a value on which there

 is no return statement. This means the execution may fall through without

 returning a meaningful result to the caller. (Use -noret to inhibit

 warning)

debug0.с:34:13: Function main declared without parameter list

 A function declaration does not have a parameter list. (Use -noparams

 to inhibit warning)

debug0.с: (in function main)

debug0.с:36:22: Undocumented use of global array

 A checked global variable is used in the function, but not listed in its

 globals clause. By default, only globals specified in .lcl files are

 checked.

 To check all globals, use +allglobals. To check globals selectively use

 /*@checked@*/ in the global declaration. (Use -globs to inhibit warning)

debug0.с:36:17: Undetected modification possible from call to unconstrained

function sort: sort

 An unconstrained function is called in a function body where

 modifications are checked. Since the unconstrained function may modify

 anything, there may be undetected modifications in the checked function.

 (Use -modunconnomods to inhibit warning)

debug0.c:36:17: Return value (type int) ignored: sort(array, 5)

 Result returned by function call is not used. If this is intended, can

 cast result to (void) to eliminate message. (Use -retvalint to inhibit

 warning)

debug0.c:37:14: Path with no return in function declared to return int

debug0.c:6:18: Variable exported but not used outside debug0: array

 A declaration is exported, but not used outside this module. Declaration

 can use static qualifier. (Use -exportlocal to inhibit warning)

debug0.c:14:13: Function exported but not used outside debug0: sort

 debug0.c:15:17: Definition of sort

debug0.c:6:18: Variable array exported but not declared in header file

 A variable declaration is exported, but does not appear in a header

 file. (Used with exportheader.) (Use -exportheadervar to inhibit warning)

debug0.c:14:13: Function sort exported but not declared in header file

 A declaration is exported, but does not appear in a header file. (Use

 -exportheader to inhibit warning)

debug0.c:15:17: Definition of sort

Finished checking - 22 code warnings

$

Утилита

выражает неудовольствие по поводу объявления функций в старом стиле (не ANSI) и несоответствия типов значений, возвращаемых функциями, и самими величинами, которые они возвращают (или нет) в действительности. Эти предупреждения не влияют на работу программы, но должны быть выведены.