ioS开发－－Warning警告处理

去除警告的方法：

#pragma clang diagnostic push
#pragma clang diagnostic ignored"-Wunused-function"
local void free_linkedlist(ll)
linkedlist_data* ll;
{
    free_datablock(ll->first_block);
    ll->first_block = ll->last_block = NULL;
}
#pragma clang diagnostic pop

上述的代码块中，正常的代码是没有下方这些代码的。但是呢，这个方法我是已经写了，但是在项目中没有运用到，所以会报出这样的错误，如图错误信息图所示：

代码块：

#pragma clang diagnostic push
#pragma clang diagnostic ignored"-Wunused-function"

// edit code

#pragma clang diagnostic pop

错误信息图：

错误信息图.png

在Xcode中选中警告的消息，右击选择Reveal in Log，然后右边会有报告的消息

-Wunused-function

所以上面去除警告是使用

-Wunused-function

这个来写的。其他的警告同理做法就能去除。

Snip20161122_3.png

示例：
我们知道，UIAlertView虽然简单易用，但是呢Apple在iOS 9.0的时候丢弃这个类了，我们在其头文件中可以看到

NS_CLASS_DEPRECATED_IOS(2_0, 9_0, "UIAlertView is deprecated. Use UIAlertController with a preferredStyle of UIAlertControllerStyleAlert instead") __TVOS_PROHIBITED

所以平时用到这个方法的时候，项目中Xcode就会给这个地方给出警告。但是也有办法处理这样的警告，如下图所示：

[email protected]

下方罗列出来是一些iOS中常见的一些警告消息，在使用第三方库或者Apple官方过时的方法的时候，都会报警告。

1. Semantic Warnings（语义警告）

Warning	Message
-WCFString-literal	input conversion stopped due to an input byte that does not belong to the input codeset UTF-8
-WNSObject-attribute	__attribute ((NSObject)) may be put on a typedef only, attribute is ignored
-Wabstract-vbase-init	initializer for virtual base class %0 of abstract class %1 will never be used
-Waddress-of-array-temporary	pointer is initialized by a temporary array, which will be destroyed at the end of the full-expression
-Warc-maybe-repeated-use-of-weak	"weak %select{variable property implicit property instance variable}0 %1 may be accessed multiple times in this %select{function method block lambda}2 and may be unpredictably set to nil assign to a strong variable to keep the object alive
-Warc-non-pod-memaccess	%select{destination for source of}0 this %1 call is a pointer to ownership-qualified type %2
-Warc-performSelector-leaks	performSelector may cause a leak because its selector is unknown
-Warc-repeated-use-of-weak	"weak %select{variable property implicit property instance variable}0 %1 is accessed multiple times in this %select{function method block lambda}2 but may be unpredictably set to nil assign to a strong variable to keep the object alive
-Warc-retain-cycles	capturing %0 strongly in this block is likely to lead to a retain cycle
-Warc-unsafe-retained-assign	assigning retained object to unsafe property object will be released after assignment
-Warc-unsafe-retained-assign	assigning %select{array literal dictionary literal numeric literal boxed expression should not happen block literal}0 to a weak %select{property variable}1 object will be released after assignment
-Warc-unsafe-retained-assign	assigning retained object to %select{weak unsafe_unretained}0 %select{property variable}1 object will be released after assignment
-Warray-bounds	array index %0 is past the end of the array (which contains %1 element%s2)
-Warray-bounds	array index %0 is before the beginning of the array
-Warray-bounds	'static' has no effect on zero-length arrays
-Warray-bounds	array argument is too small contains %0 elements, callee requires at least %1
-Warray-bounds-pointer-arithmetic	the pointer incremented by %0 refers past the end of the array (that contains %1 element%s2)
-Warray-bounds-pointer-arithmetic	the pointer decremented by %0 refers before the beginning of the array
-Wassign-enum	integer constant not in range of enumerated type %0
-Watomic-property-with-user-defined-accessor	writable atomic property %0 cannot pair a synthesized %select{getter setter}1 with a user defined %select{getter setter}2
-Wattributes	unknown attribute %0 ignored
-Wauto-var-id	'auto' deduced as 'id' in declaration of %0
-Wavailability	unknown platform %0 in availability macro
-Wavailability	overriding method %select{introduced after deprecated before obsoleted before}0 overridden method on %1 (%2 vs. %3)
-Wavailability	availability does not match previous declaration
-Wavailability	overriding method cannot be unavailable on %0 when its overridden method is available
-Wavailability	feature cannot be %select{introduced deprecated obsoleted}0 in %1 version %2 before it was %select{introduced deprecated obsoleted}3 in version %4 attribute ignored
-Wbad-function-cast	cast from function call of type %0 to non-matching type %1
-Wbitfield-constant-conversion	implicit truncation from %2 to bitfield changes value from %0 to %1
-Wbitwise-op-parentheses	'&' within '\'
-Wbool-conversion	"initialization of pointer of type %0 to null from a constant boolean " "expression
-Wbridge-cast	%0 cannot bridge to %1
-Wbridge-cast	%0 bridges to %1, not %2
-Wbuiltin-requires-header	declaration of built-in function '%0' requires inclusion of the header stdio.h
-Wbuiltin-requires-header	declaration of built-in function '%0' requires inclusion of the header setjmp.h
-Wbuiltin-requires-header	declaration of built-in function '%0' requires inclusion of the header ucontext.h
-Wc++-compat	%select{ empty }0%select{struct union}1 has size 0 in C, %select{size 1 non-zero size}2 in C++
-Wc++11-compat	explicit instantiation cannot be 'inline'
-Wc++11-compat	explicit instantiation of %0 must occur at global scope
-Wc++11-compat	explicit instantiation of %0 not in a namespace enclosing %1
-Wc++11-compat	explicit instantiation of %q0 must occur in namespace %1
-Wc++11-narrowing	constant expression evaluates to %0 which cannot be narrowed to type %1 in C++11
-Wc++11-narrowing	type %0 cannot be narrowed to %1 in initializer list in C++11
-Wc++11-narrowing	non-constant-expression cannot be narrowed from type %0 to %1 in initializer list in C++11
-Wc++98-c++11-compat	type definition in a constexpr %select{function constructor}0 is incompatible with C++ standards before C++1y
-Wc++98-c++11-compat	use of this statement in a constexpr %select{function constructor}0 is incompatible with C++ standards before C++1y
-Wc++98-c++11-compat	init-captures.def warn_cxx11_compat_init_capture : Warning "initialized lambda captures are incompatible with C++ standards " "before C++1y
-Wc++98-c++11-compat	variable declaration in a constexpr %select{function constructor}0 is incompatible with C++ standards before C++1y
-Wc++98-c++11-compat	constexpr function with no return statements is incompatible with C++ standards before C++1y
-Wc++98-c++11-compat	multiple return statements in constexpr function is incompatible with C++ standards before C++1y
-Wc++98-c++11-compat	variable templates are incompatible with C++ standards before C++1y
-Wc++98-compat	substitution failure due to access control is incompatible with C++98
-Wc++98-compat	%select{anonymous struct union}0 member %1 with a non-trivial %select{constructor copy constructor move constructor copy assignment operator move assignment operator destructor}2 is incompatible with C++98
-Wc++98-compat	enumeration type in nested name specifier is incompatible with C++98
-Wc++98-compat	static data member %0 in union is incompatible with C++98
-Wc++98-compat	default template arguments for a function template are incompatible with C++98
-Wc++98-compat	scalar initialized from empty initializer list is incompatible with C++98
-Wc++98-compat	befriending %1 without '%select{struct interface union class enum}0' keyword is incompatible with C++98
-Wc++98-compat	use of null pointer as non-type template argument is incompatible with C++98
-Wc++98-compat	friend declaration naming a member of the declaring class is incompatible with C++98
-Wc++98-compat	non-class friend type %0 is incompatible with C++98
-Wc++98-compat	befriending enumeration type %0 is incompatible with C++98
-Wc++98-compat	use of non-static data member %0 in an unevaluated context is incompatible with C++98
-Wc++98-compat	friend function %0 would be implicitly redefined in C++98
-Wc++98-compat	%select{class template class template partial variable template variable template partial function template member function static data member member class member enumeration}0 specialization of %1 outside namespace %2 is incompatible with C++98÷
-Wc++98-compat	reference initialized from initializer list is incompatible with C++98
-Wc++98-compat	redundant parentheses surrounding address non-type template argument are incompatible with C++98
-Wc++98-compat	initialization of initializer_list object is incompatible with C++98
-Wc++98-compat	use of 'template' keyword outside of a template is incompatible with C++98
-Wc++98-compat	non-type template argument referring to %select{function object}0 %1 with internal linkage is incompatible with C++98
-Wc++98-compat	use of 'typename' outside of a template is incompatible with C++98
-Wc++98-compat	passing object of trivial but non-POD type %0 through variadic %select{function block method constructor}1 is incompatible with C++98
-Wc++98-compat	goto would jump into protected scope in C++98
-Wc++98-compat	constructor call from initializer list is incompatible with C++98
-Wc++98-compat	'auto' type specifier is incompatible with C++98
-Wc++98-compat	delegating constructors are incompatible with C++98
-Wc++98-compat	'constexpr' specifier is incompatible with C++98
-Wc++98-compat	inheriting constructors are incompatible with C++98
-Wc++98-compat	explicit conversion functions are incompatible with C++98
-Wc++98-compat	switch case would be in a protected scope in C++98
-Wc++98-compat	'%0' type specifier is incompatible with C++98
-Wc++98-compat	indirect goto might cross protected scopes in C++98
-Wc++98-compat-pedantic	cast between pointer-to-function and pointer-to-object is incompatible with C++98
-Wc++98-compat-pedantic	implicit conversion from array size expression of type %0 to %select{integral enumeration}1 type %2 is incompatible with C++98
-Wcast-align	cast from %0 to %1 increases required alignment from %2 to %3
-Wcast-of-sel-type	cast of type %0 to %1 is deprecated use sel_getName instead
-Wchar-subscripts	array subscript is of type 'char'
-Wconditional-uninitialized	variable %0 may be uninitialized when %select{used here captured by block}1
-Wconstant-logical-operand	use of logical '%0' with constant operand
-Wconstexpr-not-const	'constexpr' non-static member function will not be implicitly 'const' in C++1y add 'const' to avoid a change in behavior
-Wconsumed	state of variable '%0' must match at the entry and exit of loop
-Wconsumed	parameter '%0' not in expected state when the function returns: expected '%1', observed '%2'
-Wconsumed	argument not in expected state expected '%0', observed '%1'
-Wconsumed	invalid invocation of method '%0' on a temporary object while it is in the '%1' state
-Wconsumed	return state set for an unconsumable type '%0'
-Wconsumed	consumed analysis attribute is attached to member of class '%0' which isn't marked as consumable
-Wconsumed	invalid invocation of method '%0' on object '%1' while it is in the '%2' state
-Wconsumed	return value not in expected state expected '%0', observed '%1'
-Wconversion	implicit conversion discards imaginary component: %0 to %1
-Wconversion	non-type template argument with value '%0' converted to '%1' for unsigned template parameter of type %2
-Wconversion	implicit conversion loses floating-point precision: %0 to %1
-Wconversion	implicit conversion loses integer precision: %0 to %1
-Wconversion	non-type template argument value '%0' truncated to '%1' for template parameter of type %2
-Wconversion	implicit conversion turns vector to scalar: %0 to %1
-Wconversion	implicit conversion turns floating-point number into integer: %0 to %1
-Wcovered-switch-default	default label in switch which covers all enumeration values
-Wcustom-atomic-properties	atomic by default property %0 has a user defined %select{getter setter}1 (property should be marked 'atomic' if this is intended)
-Wdangling-field	initializing pointer member %0 with the stack address of parameter %1
-Wdangling-field	binding reference %select{ subobject of }1member %0 to a temporary value
-Wdangling-field	binding reference member %0 to stack allocated parameter %1
-Wdangling-initializer-list	array backing the initializer list will be destroyed at the end of %select{the full-expression the constructor}0
-Wdelete-incomplete	deleting pointer to incomplete type %0 may cause undefined behavior
-Wdelete-non-virtual-dtor	delete called on %0 that is abstract but has non-virtual destructor
-Wdelete-non-virtual-dtor	delete called on %0 that has virtual functions but non-virtual destructor
-Wdeprecated	access declarations are deprecated use using declarations instead
-Wdeprecated	definition of implicit copy %select{constructor assignment operator}1 for %0 is deprecated because it has a user-declared %select{copy %select{assignment operator constructor}1 destructor}2
-Wdeprecated	dynamic exception specifications are deprecated
-Wdeprecated-increment-bool	incrementing expression of type bool is deprecated
-Wdeprecated-objc-isa-usage	assignment to Objective-C's isa is deprecated in favor of object_setClass()
-Wdeprecated-objc-isa-usage	direct access to Objective-C's isa is deprecated in favor of object_getClass()
-Wdeprecated-objc-pointer-introspection	bitmasking for introspection of Objective-C object pointers is strongly discouraged
-Wdeprecated-objc-pointer-introspection-performSelector	warn_objc_pointer_masking.Text
-Wdeprecated-writable-strings	dummy warning to enable -fconst-strings
-Wdirect-ivar-access	instance variable %0 is being directly accessed
-Wdistributed-object-modifiers	conflicting distributed object modifiers on return type in implementation of %0
-Wdistributed-object-modifiers	conflicting distributed object modifiers on parameter type in implementation of %0
-Wdivision-by-zero	division by zero is undefined
-Wdivision-by-zero	remainder by zero is undefined
-Wdocumentation	parameter '%0' not found in the function declaration
-Wdocumentation	not a Doxygen trailing comment
-Wduplicate-enum	element %0 has been implicitly assigned %1 which another element has been assigned
-Wduplicate-method-match	multiple declarations of method %0 found and ignored
-Wdynamic-class-memaccess	%select{destination for source of first operand of second operand of}0 this %1 call is a pointer to dynamic class %2 vtable pointer will be %select{overwritten copied moved compared}3
-Wempty-body	switch statement has empty body
-Wempty-body	for loop has empty body
-Wempty-body	if statement has empty body
-Wempty-body	range-based for loop has empty body
-Wempty-body	while loop has empty body
-Wenum-compare	comparison of two values with different enumeration types%diff{ ($ and $) }0,1
-Wenum-conversion	implicit conversion from enumeration type %0 to different enumeration type %1
-Wexit-time-destructors	declaration requires an exit-time destructor
-Wexplicit-ownership-type	method parameter of type %0 with no explicit ownership
-Wextern-c-compat	%select{ empty }0%select{struct union}1 has size 0 in C, %select{size 1 non-zero size}2 in C++
-Wextern-initializer	'extern' variable has an initializer
-Wfloat-equal	comparing floating point with == or != is unsafe
-Wformat	"data argument position '%0' exceeds the number of data arguments (%1)
-Wformat	position arguments in format strings start counting at 1 (not 0)
-Wformat	invalid position specified for %select{field width field precision}0
-Wformat	cannot mix positional and non-positional arguments in format string
-Wformat	values of type '%0' should not be used as format arguments add an explicit cast to %1 instead
-Wformat	format specifies type %0 but the argument has type %1
-Wformat	zero field width in scanf format string is unused
-Wformat	no closing ']' for '%%[' in scanf format string
-Wformat	format string should not be a wide string
-Wformat	format string contains '\0' within the string body
-Wformat	'%select{ '\'.}0' specified field %select{width precision}0 is missing a matching 'int' argument
-Wformat	field %select{width precision}0 should have type %1, but argument has type %2
-Wformat	%select{field width precision}0 used with '%1' conversion specifier, resulting in undefined behavior
-Wformat	format string missing
-Wformat	incomplete format specifier
-Wformat	flag '%0' results in undefined behavior with '%1' conversion specifier
-Wformat	flag '%0' is ignored when flag '%1' is present
-Wformat	more '%%' conversions than data arguments
-Wformat	length modifier '%0' results in undefined behavior or no effect with '%1' conversion specifier
-Wformat-extra-args	data argument not used by format string
-Wformat-invalid-specifier	invalid conversion specifier '%0'
-Wformat-nonliteral	format string is not a string literal
-Wformat-security	format string is not a string literal (potentially insecure)
-Wformat-zero-length	format string is empty
-Wgcc-compat	GCC does not allow the 'cleanup' attribute argument to be anything other than a simple identifier
-Wglobal-constructors	declaration requires a global constructor
-Wglobal-constructors	declaration requires a global destructor
-Wgnu-conditional-omitted-operand	use of GNU ?: conditional expression extension, omitting middle operand
-Wheader-hygiene	using namespace directive in global context in header
-Widiomatic-parentheses	using the result of an assignment as a condition without parentheses
-Wignored-attributes	'malloc' attribute only applies to functions returning a pointer type
-Wignored-attributes	%0 attribute only applies to %select{functions unions variables and functions functions and methods parameters functions, methods and blocks functions, methods, and classes functions, methods, and parameters classes variables methods variables, functions and labels fields and global variables structs variables, functions and tag types thread-local variables variables and fields variables, data members and tag types types and namespaces Objective-C interfaces}1
-Wignored-attributes	'%0' attribute cannot be specified on a definition
-Wignored-attributes	__weak attribute cannot be specified on an automatic variable when ARC is not enabled
-Wignored-attributes	Objective-C GC does not allow weak variables on the stack
-Wignored-attributes	__weak attribute cannot be specified on a field declaration
-Wignored-attributes	attribute %0 cannot be applied to %select{functions Objective-C method}1 without return value
-Wignored-attributes	attribute declaration must precede definition
-Wignored-attributes	attribute %0 is ignored, place it after \"%select{class struct union interface enum}1\" to apply attribute to type declaration
-Wignored-attributes	__declspec attribute %0 is not supported
-Wignored-attributes	attribute %0 ignored, because it cannot be applied to a type
-Wignored-attributes	attribute %0 after definition is ignored
-Wignored-attributes	%0 attribute ignored
-Wignored-attributes	'sentinel' attribute only supported for variadic %select{functions blocks}0
-Wignored-attributes	'sentinel' attribute requires named arguments
-Wignored-attributes	'%0' only applies to %select{function pointer Objective-C object or block pointer}1 types type here is %2
-Wignored-attributes	'nonnull' attribute applied to function with no pointer arguments
-Wignored-attributes	%0 attribute can only be applied to instance variables or properties
-Wignored-attributes	unknown visibility %0
-Wignored-attributes	%0 calling convention ignored on variadic function
-Wignored-attributes	%0 only applies to variables with static storage duration and functions
-Wignored-attributes	ibaction attribute can only be applied to Objective-C instance methods
-Wignored-attributes	#pramga ms_struct can not be used with dynamic classes or structures
-Wignored-attributes	transparent union definition must contain at least one field transparent_union attribute ignored
-Wignored-attributes	first field of a transparent union cannot have %select{floating point vector}0 type %1 transparent_union attribute ignored
-Wignored-attributes	'gnu_inline' attribute requires function to be marked 'inline', attribute ignored
-Wignored-attributes	calling convention %0 ignored for this target
-Wignored-attributes	transparent_union attribute can only be applied to a union definition attribute ignored
-Wignored-attributes	%select{alignment size}0 of field %1 (%2 bits) does not match the %select{alignment size}0 of the first field in transparent union transparent_union attribute ignored
-Wignored-attributes	attribute %0 is already applied
-Wignored-attributes	%0 attribute ignored for field of type %1
-Wignored-attributes	%0 attribute ignored when parsing type
-Wignored-attributes	%0 attribute only applies to %select{functions methods properties}1 that return %select{an Objective-C object a pointer a non-retainable pointer}2
-Wignored-attributes	%0 attribute only applies to %select{Objective-C object pointer}1 parameters
-Wignored-attributes	attribute %0 is already applied with different parameters
-Wignored-attributes	%0 attribute argument not supported: %1
-Wignored-qualifiers	"'%0' type qualifier%s1 on return type %plural{1:has :have}1 no effect
-Wignored-qualifiers	ARC %select{unused unsafe_unretained strong weak autoreleasing}0 lifetime qualifier on return type is ignored
-Wimplicit-atomic-properties	property is assumed atomic by default
-Wimplicit-atomic-properties	property is assumed atomic when auto-synthesizing the property
-Wimplicit-fallthrough	fallthrough annotation in unreachable code
-Wimplicit-fallthrough	unannotated fall-through between switch labels
-Wimplicit-fallthrough	fallthrough annotation does not directly precede switch label
-Wimplicit-function-declaration	implicit declaration of function %0
-Wimplicit-function-declaration	use of unknown builtin %0
-Wimplicit-retain-self	"block implicitly retains 'self' explicitly mention 'self' to indicate this is intended behavior
-Wincompatible-library-redeclaration	incompatible redeclaration of library function %0
-Wincomplete-implementation	method definition for %0 not found
-Winherited-variadic-ctor	inheriting constructor does not inherit ellipsis
-Winitializer-overrides	subobject initialization overrides initialization of other fields within its enclosing subobject
-Winitializer-overrides	initializer overrides prior initialization of this subobject
-Wint-to-pointer-cast	cast to %1 from smaller integer type %0
-Wint-to-void-pointer-cast	cast to %1 from smaller integer type %0
-Winvalid-iboutlet	IBOutletCollection properties should be copy/strong and not assign
-Winvalid-iboutlet	%select{instance variable property}2 with %0 attribute must be an object type (invalid %1)
-Winvalid-noreturn	function %0 declared 'noreturn' should not return
-Winvalid-noreturn	function declared 'noreturn' should not return
-Wlarge-by-value-copy	return value of %0 is a large (%1 bytes) pass-by-value object pass it by reference instead ?
-Wlarge-by-value-copy	%0 is a large (%1 bytes) pass-by-value argument pass it by reference instead ?
-Wliteral-conversion	implicit conversion from %0 to %1 changes value from %2 to %3
-Wliteral-range	magnitude of floating-point constant too large for type %0 maximum is %1
-Wliteral-range	magnitude of floating-point constant too small for type %0 minimum is %1
-Wlogical-not-parentheses	logical not is only applied to the left hand side of this comparison
-Wlogical-op-parentheses	'&&' within '\'
-Wloop-analysis	variable%select{s %1 s %1 and %2 s %1, %2, and %3 s %1, %2, %3, and %4}0 used in loop condition not modified in loop body
-Wloop-analysis	variable %0 is %select{decremented incremented}1 both in the loop header and in the loop body
-Wmethod-signatures	conflicting parameter types in implementation of %0: %1 vs %2
-Wmethod-signatures	conflicting return type in implementation of %0: %1 vs %2
-Wmicrosoft	extra qualification on member %0
-Wmismatched-method-attributes	attributes on method implementation and its declaration must match
-Wmismatched-parameter-types	conflicting parameter types in implementation of %0%diff{: $ vs $ }1,2
-Wmismatched-return-types	conflicting return type in implementation of %0%diff{: $ vs $ }1,2
-Wmissing-braces	suggest braces around initialization of subobject
-Wmissing-declarations	'%0' ignored on this declaration
-Wmissing-field-initializers	missing field '%0' initializer
-Wmissing-method-return-type	method has no return type specified defaults to 'id'
-Wmissing-noreturn	block could be declared with attribute 'noreturn'
-Wmissing-noreturn	%select{function method}0 %1 could be declared with attribute 'noreturn'
-Wmissing-prototypes	no previous prototype for function %0
-Wmissing-variable-declarations	no previous extern declaration for non-static variable %0
-Wmultiple-move-vbase	defaulted move assignment operator of %0 will move assign virtual base class %1 multiple times
-Wnested-anon-types	anonymous types declared in an anonymous union/struct are an extension
-Wnon-literal-null-conversion	"expression which evaluates to zero treated as a null pointer constant of " "type %0
-Wnon-pod-varargs	cannot pass object of %select{non-POD non-trivial}0 type %1 through variadic %select{function block method constructor}2 call will abort at runtime
-Wnon-pod-varargs	cannot pass %select{non-POD non-trivial}0 object of type %1 to variadic %select{function block method constructor}2 expected type from format string was %3
-Wnon-pod-varargs	second argument to 'va_arg' is of ARC ownership-qualified type %0
-Wnon-pod-varargs	second argument to 'va_arg' is of non-POD type %0
-Wnon-virtual-dtor	%0 has virtual functions but non-virtual destructor
-Wnonnull	null passed to a callee which requires a non-null argument
-Wnull-arithmetic	comparison between NULL and non-pointer %select{(%1 and NULL) (NULL and %1)}0
-Wnull-arithmetic	use of NULL in arithmetic operation
-Wnull-dereference	indirection of non-volatile null pointer will be deleted, not trap
-Wobjc-autosynthesis-property-ivar-name-match	autosynthesized property %0 will use %select{ synthesized}1 instance variable %2, not existing instance variable %3
-Wobjc-forward-class-redefinition	redefinition of forward class %0 of a typedef name of an object type is ignored
-Wobjc-interface-ivars	declaration of instance variables in the interface is deprecated
-Wobjc-literal-compare	direct comparison of %select{an array literal a dictionary literal a numeric literal a boxed expression }0 has undefined behavior
-Wobjc-literal-missing-atsign	string literal must be prefixed by '@'
-Wobjc-method-access	class method %objcclass0 not found (return type defaults to 'id')
-Wobjc-method-access	instance method %objcinstance0 not found (return type defaults to 'id')
-Wobjc-method-access	instance method %0 is being used on 'Class' which is not in the root class
-Wobjc-method-access	instance method %0 found instead of class method %1
-Wobjc-method-access	class method %objcclass0 not found (return type defaults to 'id') did you mean %objcclass2?
-Wobjc-method-access	instance method %objcinstance0 not found (return type defaults to 'id') did you mean %objcinstance2?
-Wobjc-missing-property-synthesis	"auto property synthesis is synthesizing property not explicitly synthesized
-Wobjc-missing-super-calls	method possibly missing a [super %0] call
-Wobjc-noncopy-retain-block-property	"retain'ed block property does not copy the block " "- use copy attribute instead
-Wobjc-nonunified-exceptions	can not catch an exception thrown with @throw in C++ in the non-unified exception model
-Wobjc-property-implementation	property %0 requires method %1 to be defined - use @synthesize, @dynamic or provide a method implementation in this class implementation
-Wobjc-property-implementation	property %0 requires method %1 to be defined - use @dynamic or provide a method implementation in this category
-Wobjc-property-implicit-mismatch	"primary property declaration is implicitly strong while redeclaration in class extension is weak
-Wobjc-property-matches-cocoa-ownership-rule	property's synthesized getter follows Cocoa naming convention for returning 'owned' objects
-Wobjc-property-no-attribute	no 'assign', 'retain', or 'copy' attribute is specified - 'assign' is assumed
-Wobjc-property-no-attribute	default property attribute 'assign' not appropriate for non-GC object
-Wobjc-property-synthesis	"auto property synthesis will not synthesize property '%0' because it cannot share an ivar with another synthesized property
-Wobjc-property-synthesis	auto property synthesis will not synthesize property '%0' because it is 'readwrite' but it will be synthesized 'readonly' via another property
-Wobjc-protocol-method-implementation	category is implementing a method which will also be implemented by its primary class
-Wobjc-protocol-property-synthesis	auto property synthesis will not synthesize property declared in a protocol
-Wobjc-redundant-literal-use	using %0 with a literal is redundant
-Wobjc-root-class	class %0 defined without specifying a base class
-Wobjc-string-compare	direct comparison of a string literal has undefined behavior
-Wobjc-string-concatenation	concatenated NSString literal for an NSArray expression - possibly missing a comma
-Wover-aligned	type %0 requires %1 bytes of alignment and the default allocator only guarantees %2 bytes
-Woverloaded-shift-op-parentheses	overloaded operator %select{'\'}0 has lower precedence than comparison operator
-Woverloaded-virtual	%q0 hides overloaded virtual %select{function functions}1
-Woverriding-method-mismatch	conflicting distributed object modifiers on parameter type in declaration of %0
-Woverriding-method-mismatch	conflicting parameter types in declaration of %0: %1 vs %2
-Woverriding-method-mismatch	conflicting variadic declaration of method and its implementation
-Woverriding-method-mismatch	conflicting return type in declaration of %0: %1 vs %2
-Woverriding-method-mismatch	conflicting distributed object modifiers on return type in declaration of %0
-Woverriding-method-mismatch	conflicting return type in declaration of %0%diff{: $ vs $}1,2
-Woverriding-method-mismatch	conflicting parameter types in declaration of %0%diff{: $ vs $}1,2
-Wpacked	packed attribute is unnecessary for %0
-Wpadded	padding size of %0 with %1 %select{bytebit}2%select{s}3 to alignment boundary
-Wpadded	padding %select{struct interface class}0 %1 with %2 %select{byte bit}3%select{s}4 to align %5
-Wpadded	padding %select{struct interface class}0 %1 with %2 %select{byte bit}3%select{s}4 to align anonymous bit-field
-Wparentheses	%0 has lower precedence than %1 %1 will be evaluated first
-Wparentheses	using the result of an assignment as a condition without parentheses
-Wparentheses	operator '?:' has lower precedence than '%0' '%0' will be evaluated first
-Wparentheses-equality	equality comparison with extraneous parentheses
-Wpointer-arith	subtraction of pointers to type %0 of zero size has undefined behavior
-Wpredefined-identifier-outside-function	predefined identifier is only valid inside function
-Wprivate-extern	use of private_extern on a declaration may not produce external symbol private to the linkage unit and is deprecated
-Wprotocol	method %0 in protocol not implemented
-Wprotocol-property-synthesis-ambiguity	property of type %0 was selected for synthesis
-Wreadonly-iboutlet-property	readonly IBOutlet property '%0' when auto-synthesized may not work correctly with 'nib' loader
-Wreadonly-setter-attrs	property attributes '%0' and '%1' are mutually exclusive
-Wreceiver-expr	receiver type %0 is not 'id' or interface pointer, consider casting it to 'id'
-Wreceiver-forward-class	receiver type %0 for instance message is a forward declaration
-Wreceiver-is-weak	"weak %select{receiver property implicit property}0 may be unpredictably set to nil
-Wreinterpret-base-class	'reinterpret_cast' %select{from to}3 class %0 %select{to from}3 its %select{virtual base base at non-zero offset}2 %1 behaves differently from 'static_cast'
-Wreorder	%select{field base class}0 %1 will be initialized after %select{field base}2 %3
-Wrequires-super-attribute	%0 attribute cannot be applied to %select{methods in protocols dealloc}1
-Wreturn-stack-address	returning address of label, which is local
-Wreturn-stack-address	returning reference to local temporary object
-Wreturn-stack-address	address of stack memory associated with local variable %0 returned
-Wreturn-stack-address	returning address of local temporary object
-Wreturn-stack-address	reference to stack memory associated with local variable %0 returned
-Wreturn-type	non-void %select{function method}1 %0 should return a value, DefaultError
-Wreturn-type	control may reach end of non-void function
-Wreturn-type	control reaches end of non-void function
-Wreturn-type-c-linkage	%0 has C-linkage specified, but returns user-defined type %1 which is incompatible with C
-Wreturn-type-c-linkage	%0 has C-linkage specified, but returns incomplete type %1 which could be incompatible with C
-Wsection	section does not match previous declaration
-Wselector	creating selector for nonexistent method %0
-Wselector-type-mismatch	multiple selectors named %0 found
-Wself-assign	explicitly assigning a variable of type %0 to itself
-Wself-assign-field	assigning %select{field instance variable}0 to itself
-Wsentinel	not enough variable arguments in %0 declaration to fit a sentinel
-Wsentinel	"missing sentinel in %select{function call method dispatch block call}0
-Wshadow	declaration shadows a %select{" "local variable" "variable in %2" "static data member of %2 " "field of %2}1
-Wshadow-ivar	local declaration of %0 hides instance variable
-Wshift-count-negative	shift count is negative
-Wshift-count-overflow	shift count = width of type
-Wshift-op-parentheses	operator '%0' has lower precedence than '%1' '%1' will be evaluated first
-Wshift-overflow	signed shift result (%0) requires %1 bits to represent, but %2 only has %3 bits
-Wshift-sign-overflow	signed shift result (%0) sets the sign bit of the shift expression's type (%1) and becomes negative
-Wshorten-64-to-32	implicit conversion loses integer precision: %0 to %1
-Wsign-compare	comparison of integers of different signs: %0 and %1
-Wsign-conversion	implicit conversion changes signedness: %0 to %1
-Wsign-conversion	operand of ? changes signedness: %0 to %1
-Wsizeof-array-argument	sizeof on array function parameter will return size of %0 instead of %1
-Wsizeof-array-decay	sizeof on pointer operation will return size of %0 instead of %1
-Wsizeof-pointer-memaccess	'%0' call operates on objects of type %1 while the size is based on a " "different type %2
-Wsizeof-pointer-memaccess	argument to 'sizeof' in %0 call is the same pointer type %1 as the %select{destination source}2 expected %3 or an explicit length
-Wsometimes-uninitialized	variable %0 is %select{used captured}1 uninitialized whenever %select{'%3' condition is %select{true false}4 '%3' loop %select{is entered exits because its condition is false}4 '%3' loop %select{condition is true exits because its condition is false}4 switch %3 is taken its declaration is reached %3 is called}2
-Wstatic-local-in-inline	non-constant static local variable in inline function may be different in different files
-Wstatic-self-init	static variable %0 is suspiciously used within its own initialization
-Wstrict-selector-match	multiple methods named %0 found
-Wstring-compare	result of comparison against %select{a string literal@encode}0 is unspecified (use strncmp instead)
-Wstring-conversion	implicit conversion turns string literal into bool: %0 to %1
-Wstring-plus-char	adding %0 to a string pointer does not append to the string
-Wstring-plus-int	adding %0 to a string does not append to the string
-Wstrlcpy-strlcat-size	size argument in %0 call appears to be size of the source expected the size of the destination
-Wstrncat-size	the value of the size argument to 'strncat' is wrong
-Wstrncat-size	the value of the size argument in 'strncat' is too large, might lead to a " "buffer overflow
-Wstrncat-size	size argument in 'strncat' call appears " "to be size of the source
-Wsuper-class-method-mismatch	method parameter type %diff{$ does not match super class method parameter type $does not match super class method parameter type}0,1
-Wswitch	enumeration value %0 not handled in switch
-Wswitch	overflow converting case value to switch condition type (%0 to %1)
-Wswitch	enumeration values %0 and %1 not handled in switch
-Wswitch	case value not in enumerated type %0
-Wswitch	enumeration values %0, %1, and %2 not handled in switch
-Wswitch	%0 enumeration values not handled in switch: %1, %2, %3...
-Wswitch-enum	enumeration value %0 not explicitly handled in switch
-Wswitch-enum	%0 enumeration values not explicitly handled in switch: %1, %2, %3...
-Wswitch-enum	enumeration values %0 and %1 not explicitly handled in switch
-Wswitch-enum	enumeration values %0, %1, and %2 not explicitly handled in switch
-Wtautological-compare	%select{self-array }0comparison always evaluates to %select{false true a constant}1
-Wtautological-compare	comparison of unsigned%select{ enum}2 expression %0 is always %1
-Wtautological-compare	comparison of %0 unsigned%select{ enum}2 expression is always %1
-Wtautological-constant-out-of-range-compare	comparison of constant %0 with expression of type %1 is always %select{false true}2
-Wthread-safety-analysis	expecting mutex '%0' to be locked at the end of function
-Wthread-safety-analysis	%select{reading writing}1 the value pointed to by '%0' requires locking %select{any mutex any mutex exclusively}1
-Wthread-safety-analysis	unlocking '%0' that was not locked
-Wthread-safety-analysis	mutex '%0' is locked exclusively and shared in the same scope
-Wthread-safety-analysis	expecting mutex '%0' to be locked at start of each loop
-Wthread-safety-analysis	%select{reading writing}2 variable '%0' requires locking %select{'%1'\'%1' exclusively}2
-Wthread-safety-analysis	%select{reading writing}2 the value pointed to by '%0' requires locking %select{'%1'\'%1' exclusively}2
-Wthread-safety-analysis	calling function '%0' requires %select{shared exclusive}2 lock on '%1'
-Wthread-safety-analysis	locking '%0' that is already locked
-Wthread-safety-analysis	cannot resolve lock expression
-Wthread-safety-analysis	cannot call function '%0' while mutex '%1' is locked
-Wthread-safety-analysis	mutex '%0' is still locked at the end of function
-Wthread-safety-analysis	mutex '%0' is not locked on every path through here
-Wthread-safety-analysis	%select{reading writing}1 variable '%0' requires locking %select{any mutex any mutex exclusively}1
-Wthread-safety-attributes	%0 attribute only applies to %select{fields and global variables functions and methods classes and structs}1
-Wthread-safety-attributes	'%0' only applies to pointer types type here is %1
-Wthread-safety-attributes	%0 attribute can only be applied in a context annotated with 'lockable' attribute
-Wthread-safety-attributes	ignoring %0 attribute because its argument is invalid
-Wthread-safety-attributes	%0 attribute requires arguments whose type is annotated with 'lockable' attribute type here is '%1'
-Wthread-safety-attributes	%0 attribute requires arguments that are class type or point to class type type here is '%1'
-Wthread-safety-beta	Thread safety beta warning.
-Wthread-safety-precise	calling function '%0' requires %select{shared exclusive}2 lock on '%1'
-Wthread-safety-precise	%select{reading writing}2 the value pointed to by '%0' requires locking %select{'%1'\'%1' exclusively}2
-Wthread-safety-precise	%select{reading writing}2 variable '%0' requires locking %select{'%1' \'%1' exclusively}2
-Wtype-safety	argument type %0 doesn't match specified '%1' type tag %select{that requires %3 }2
-Wtype-safety	specified %0 type tag requires a null pointer
-Wtype-safety	this type tag was not designed to be used with this function
-Wundeclared-selector	undeclared selector %0 did you mean %1?
-Wundeclared-selector	undeclared selector %0
-Wundefined-inline	inline function %q0 is not defined
-Wundefined-internal	%select{function variable}0 %q1 has internal linkage but is not defined
-Wundefined-reinterpret-cast	reinterpret_cast from %0 to %1 has undefined behavior
-Wundefined-reinterpret-cast	dereference of type %1 that was reinterpret_cast from type %0 has undefined behavior
-Wuninitialized	reference %0 is not yet bound to a value when used within its own initialization
-Wuninitialized	block pointer variable %0 is uninitialized when captured by block
-Wuninitialized	field %0 is uninitialized when used here
-Wuninitialized	reference %0 is not yet bound to a value when used here
-Wuninitialized	variable %0 is uninitialized when %select{used here captured by block}1
-Wuninitialized	variable %0 is uninitialized when used within its own initialization
-Wunneeded-internal-declaration	'static' function %0 declared in header file should be declared 'static inline'
-Wunneeded-internal-declaration	%select{function variable}0 %1 is not needed and will not be emitted
-Wunneeded-member-function	member function %0 is not needed and will not be emitted
-Wunreachable-code	will never be executed
-Wunsequenced	multiple unsequenced modifications to %0
-Wunsequenced	unsequenced modification and access to %0
-Wunsupported-friend	dependent nested name specifier '%0' for friend class declaration is not supported turning off access control for %1
-Wunsupported-friend	dependent nested name specifier '%0' for friend template declaration is not supported ignoring this friend declaration
-Wunsupported-visibility	target does not support 'protected' visibility using 'default'
-Wunused-comparison	%select{equality inequality}0 comparison result unused
-Wunused-const-variable	unused variable %0
-Wunused-exception-parameter	unused exception parameter %0
-Wunused-function	unused function %0
-Wunused-label	unused label %0
-Wunused-member-function	unused member function %0
-Wunused-parameter	unused parameter %0
-Wunused-private-field	private field %0 is not used
-Wunused-property-ivar ivar	%0 which backs the property is not referenced in this property's accessor
-Wunused-result	ignoring return value of function declared with warn_unused_result attribute
-Wunused-value	expression result unused should this cast be to 'void'?
-Wunused-value	expression result unused
-Wunused-value	ignoring return value of function declared with %0 attribute
-Wunused-variable	unused variable %0
-Wunused-volatile-lvalue	expression result unused assign into a variable to force a volatile load
-Wused-but-marked-unused	%0 was marked unused but was used
-Wuser-defined-literals	user-defined literal suffixes not starting with '_' are reserved%select{ no literal will invoke this operator}0
-Wvarargs	second argument to 'va_arg' is of promotable type %0 this va_arg has undefined behavior because arguments will be promoted to %1
-Wvarargs	'va_start' has undefined behavior with reference types
-Wvarargs	second parameter of 'va_start' not last named argument
-Wvector-conversion	incompatible vector types %select{%diff{assigning to $ from $ assigning to different types}0,1 %diff{passing $ to parameter of type $ passing to parameter of different type}0,1%diff{returning $ from a function with result type $ returning from function with different return type}0,1 %diff{converting $ to type $ converting between types}0,1 %diff{initializing $ with an expression of type $ initializing with expression of different type}0,1 %diff{sending $ to parameter of type $ sending to parameter of different type}0,1 %diff{casting $ to type $ casting between types}0,1}2
-Wvexing-parse	empty parentheses interpreted as a function declaration
-Wvexing-parse	parentheses were disambiguated as a function declaration
-Wvisibility	declaration of %0 will not be visible outside of this function
-Wvisibility	redefinition of %0 will not be visible outside of this function
-Wvla	variable length array used
-Wvla-extension	variable length arrays are a C99 feature
-Wweak-template-vtables	explicit template instantiation %0 will emit a vtable in every translation unit
-Wweak-vtables	%0 has no out-of-line virtual method definitions; its vtable will be emitted in every translation unit

2. Parser Warnings（解析器警告）

Warning	Message
-Warc-bridge-casts-disallowed-in-nonarc	'%0' casts have no effect when not using ARC
-Wattributes	unknown __declspec attribute %0 ignored
-Wavailability	'unavailable' availability overrides all other availability information
-Wc++11-compat	use of right-shift operator ('') in template argument will require parentheses in C++11
-Wc++11-compat	'auto' storage class specifier is redundant and incompatible with C++11
-Wc++98-c++11-compat	'decltype(auto)' type specifier is incompatible with C++ standards before C++1y
-Wc++98-compat	range-based for loop is incompatible with C++98
-Wc++98-compat	alias declarations are incompatible with C++98
-Wc++98-compat	in-class initialization of non-static data members is incompatible with C++98
-Wc++98-compat	defaulted function definitions are incompatible with C++98
-Wc++98-compat	rvalue references are incompatible with C++98
-Wc++98-compat	reference qualifiers on functions are incompatible with C++98
-Wc++98-compat	inline namespaces are incompatible with C++98
-Wc++98-compat	generalized initializer lists are incompatible with C++98
-Wc++98-compat	trailing return types are incompatible with C++98
-Wc++98-compat	enumeration types with a fixed underlying type are incompatible with C++98
-Wc++98-compat	alignof expressions are incompatible with C++98
-Wc++98-compat	'%0' keyword is incompatible with C++98
-Wc++98-compat	'decltype' type specifier is incompatible with C++98
-Wc++98-compat	deleted function definitions are incompatible with C++98
-Wc++98-compat	consecutive right angle brackets are incompatible with C++98 (use '> >')
-Wc++98-compat	static_assert declarations are incompatible with C++98
-Wc++98-compat	scoped enumerations are incompatible with C++98
-Wc++98-compat	lambda expressions are incompatible with C++98
-Wc++98-compat	attributes are incompatible with C++98
-Wc++98-compat	'alignas' is incompatible with C++98
-Wc++98-compat	noexcept specifications are incompatible with C++98
-Wc++98-compat	literal operators are incompatible with C++98
-Wc++98-compat	noexcept expressions are incompatible with C++98
-Wc++98-compat	'nullptr' is incompatible with C++98
-Wc++98-compat-pedantic	extra '' outside of a function is incompatible with C++98
-Wc++98-compat-pedantic	extern templates are incompatible with C++98
-Wc++98-compat-pedantic	commas at the end of enumerator lists are incompatible with C++98
-Wdangling-else	add explicit braces to avoid dangling else
-Wdeprecated	Use of 'long' with '__vector' is deprecated
-Wdeprecated-declarations	use of C-style parameters in Objective-C method declarations is deprecated
-Wdeprecated-register	'register' storage class specifier is deprecated
-Wduplicate-decl-specifier	duplicate '%0' declaration specifier
-Wextra-semi	extra ';' after member function definition
-Wextra-tokens	"extra tokens at the end of '#pragma omp %0' are ignored
-Wgcc-compat	GCC does not allow %0 attribute in this position on a function definition
-Wignored-attributes	attribute %0 ignored, because it is not attached to a declaration
-Wmicrosoft-exists	dependent %select{if_not_exists if_exists}0 declarations are ignored
-Wmissing-selector-name	%0 used as the name of the previous parameter rather than as part of the selector
-Wsemicolon-before-method-body	semicolon before method body is ignored
-Wsource-uses-openmp	"unexpected '#pragma omp ...' in program
-Wstatic-inline-explicit-instantiation	ignoring '%select{static inline}0' keyword on expli

文／i_蓝天（简书作者）
原文链接：http://www.jianshu.com/p/01659b6d9dc0