Основы программирования в Linux, Мэтью Нейл

Основы программирования в Linux

на обложку

Мэтью Нейл

Шрифт:

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.