warnings-detail-4.8.txt

# enabled by default:
#    -Waggressive-loop-optimizations
#         Warn if a loop with constant number of iterations triggers undefined behavior
#    -Wattributes
#         Warn about inappropriate attribute usage
#    -Wconversion-null
#         Warn for converting NULL from/to a non-pointer type
#    -Wcoverage-mismatch
#         Warn in case profiles in -fprofile-use do not match
#    -Wcpp
#         Warn when a #warning directive is encountered
#    -Wdeprecated
#         Warn if a deprecated compiler feature, class, method, or field is used
#    -Wdeprecated-declarations
#         Warn about uses of __attribute__((deprecated)) declarations
#    -Wdiv-by-zero
#         Warn about compile-time integer division by zero
#    -Wenum-compare
#         Warn about comparison of different enum types
#    -Wfree-nonheap-object
#         Warn when attempting to free a non-heap object
#    -Wimplicit-function-declaration
#         Warn about implicit function declarations
#    -Winherited-variadic-ctor
#         Warn about C++11 inheriting constructors when the base has a variadic constructor
#    -Wint-to-pointer-cast
#         Warn when there is a cast to a pointer from an integer of a different size
#    -Winvalid-memory-model
#         Warn when an atomic memory model parameter is known to be outside the valid range.
#    -Winvalid-offsetof
#         Warn about invalid uses of the \"offsetof\" macro
#    -Wlong-long
#         Do not warn about using \"long long\" when -pedantic
#    -Wmain
#         Warn about suspicious declarations of \"main\"
#    -Wmudflap
#         Warn about constructs not instrumented by -fmudflap
#    -Wnarrowing
#         Warn about narrowing conversions within { } that are ill-formed in C++11
#    -Wnon-template-friend
#         Warn when non-templatized friend functions are declared within a template
#    -Woverflow
#         Warn about overflow in arithmetic expressions
#    -Wpacked-bitfield-compat
#         Warn about packed bit-fields whose offset changed in GCC 4.4
#    -Wpmf-conversions
#         Warn when converting the type of pointers to member functions
#    -Wpointer-to-int-cast
#         Warn when a pointer is cast to an integer of a different size
#    -Wpragmas
#         Warn about misuses of pragmas
#    -Wproperty-assign-default
#         Warn if a property for an Objective-C object has no assign semantics specified
#    -Wprotocol
#         Warn if inherited methods are unimplemented
#    -Wpsabi
#    -Wreturn-local-addr
#         Warn about returning a pointer/reference to a local or temporary variable.
#    -Wsync-nand
#         Warn when __sync_fetch_and_nand and __sync_nand_and_fetch built-in functions are used
#    -Wunused-result
#         Warn if a caller of a function, marked with attribute warn_unused_result, does not use its return value
#    -Wvarargs
#         Warn about questionable usage of the macros used to retrieve variable arguments
#    -Wvariadic-macros
#         Warn about using variadic macros
#    -Wvirtual-move-assign
#         Warn if a virtual base has a non-trivial move assignment operator
#    -Wvla
#         Warn if a variable length array is used
-Wabi
#     Warn about things that will change when compiling with an ABI-compliant compiler
-Wabi-tag
#     Warn if a subobject has an abi_tag attribute that the complete object type does not have
-Waggregate-return
#     Warn about returning structures, unions or arrays
-Wall
#     Enable most warning messages
#    -Waddress
#         Warn about suspicious uses of memory addresses
#    -Warray-bounds
#         Warn if an array is accessed out of bounds
#    -Wc++0x-compat
#         Deprecated in favor of -Wc++11-compat
#      -Wnarrowing
#           Warn about narrowing conversions within { } that are ill-formed in C++11
#    -Wchar-subscripts
#         Warn about subscripts whose type is \"char\"
#    -Wdelete-non-virtual-dtor
#         Warn about deleting polymorphic objects with non-virtual destructors
#    -Wenum-compare
#         Warn about comparison of different enum types
#    -Wformat=1
#         Warn about printf/scanf/strftime/strfmon format string anomalies
#      -Wformat-contains-nul
#           Warn about format strings that contain NUL bytes
#      -Wformat-extra-args
#           Warn if passing too many arguments to a function for its format string
#      -Wformat-zero-length
#           Warn about zero-length formats
#      -Wnonnull
#           Warn about NULL being passed to argument slots marked as requiring non-NULL
#    -Wimplicit
#         Warn about implicit declarations
#      -Wimplicit-function-declaration
#           Warn about implicit function declarations
#      -Wimplicit-int
#           Warn when a declaration does not specify a type
#    -Winit-self
#         Warn about variables which are initialized to themselves
#    -Wmain
#         Warn about suspicious declarations of \"main\"
#    -Wmaybe-uninitialized
#         Warn about maybe uninitialized automatic variables
#    -Wmissing-braces
#         Warn about possibly missing braces around initializers
#    -Wnarrowing
#         Warn about narrowing conversions within { } that are ill-formed in C++11
#    -Wnonnull
#         Warn about NULL being passed to argument slots marked as requiring non-NULL
#    -Wparentheses
#         Warn about possibly missing parentheses
#    -Wpointer-sign
#         Warn when a pointer differs in signedness in an assignment
#    -Wreorder
#         Warn when the compiler reorders code
#    -Wreturn-type
#         Warn whenever a function's return type defaults to \"int\" (C), or about inconsistent return types (C++)
#    -Wsequence-point
#         Warn about possible violations of sequence point rules
#    -Wsign-compare
#         Warn about signed-unsigned comparisons
#    -Wsizeof-pointer-memaccess
#    -Wstrict-aliasing=3
#         Warn about code which might break strict aliasing rules
#    -Wstrict-overflow=1
#         Warn about optimizations that assume that signed overflow is undefined
#    -Wswitch
#         Warn about enumerated switches, with no default, missing a case
#    -Wuninitialized
#         Warn about uninitialized automatic variables
#      -Wmaybe-uninitialized
#           Warn about maybe uninitialized automatic variables
#    -Wunknown-pragmas
#         Warn about unrecognized pragmas
#    -Wunused
#         Enable all -Wunused- warnings
#      -Wunused-but-set-variable
#           Warn when a variable is only set, otherwise unused
#      -Wunused-function
#           Warn when a function is unused
#      -Wunused-label
#           Warn when a label is unused
#      -Wunused-local-typedefs
#           Warn when typedefs locally defined in a function are not used
#      -Wunused-value
#           Warn when an expression value is unused
#      -Wunused-variable
#           Warn when a variable is unused
#    -Wvolatile-register-var
#         Warn when a register variable is declared volatile
-Wassign-intercept
#     Warn whenever an Objective-C assignment is being intercepted by the garbage collector
-Wbad-function-cast
#     Warn about casting functions to incompatible types
-Wbuiltin-macro-redefined
#     Warn when a built-in preprocessor macro is undefined or redefined
-Wc++-compat
#     Warn about C constructs that are not in the common subset of C and C++
#    -Wenum-compare
#         Warn about comparison of different enum types
-Wcast-align
#     Warn about pointer casts which increase alignment
-Wcast-qual
#     Warn about casts which discard qualifiers
-Wcomment
#     Warn about possibly nested block comments, and C++ comments spanning more than one physical line
-Wconversion
#     Warn for implicit type conversions that may change a value
#    -Wsign-conversion
#         Warn for implicit type conversions between signed and unsigned integers
-Wctor-dtor-privacy
#     Warn when all constructors and destructors are private
-Wdeclaration-after-statement
#     Warn when a declaration is found after a statement
-Wdisabled-optimization
#     Warn when an optimization pass is disabled
-Wdouble-promotion
#     Warn about implicit conversions from \"float\" to \"double\"
-Weffc++
#     Warn about violations of Effective C++ style rules
#    -Wdelete-non-virtual-dtor
#         Warn about deleting polymorphic objects with non-virtual destructors
-Wendif-labels
#     Warn about stray tokens after #elif and #endif
-Wextra
#     Print extra (possibly unwanted) warnings
#    -Wclobbered
#         Warn about variables that might be changed by \"longjmp\" or \"vfork\"
#    -Wempty-body
#         Warn about an empty body in an if or else statement
#    -Wignored-qualifiers
#         Warn whenever type qualifiers are ignored.
#    -Wmissing-field-initializers
#         Warn about missing fields in struct initializers
#    -Wmissing-parameter-type
#         Warn about function parameters declared without a type specifier in K&R-style functions
#    -Wold-style-declaration
#         Warn for obsolescent usage in a declaration
#    -Woverride-init
#         Warn about overriding initializers without side effects
#    -Wsign-compare
#         Warn about signed-unsigned comparisons
#    -Wtype-limits
#         Warn if a comparison is always true or always false due to the limited range of the data type
#    -Wuninitialized
#         Warn about uninitialized automatic variables
#      -Wmaybe-uninitialized
#           Warn about maybe uninitialized automatic variables
#    -Wunused-but-set-parameter
#         Warn when a function parameter is only set, otherwise unused
#    -Wunused-parameter
#         Warn when a function parameter is unused
-Wfloat-equal
#     Warn if testing floating point numbers for equality
-Wformat=
#     Warn about printf/scanf/strftime/strfmon format string anomalies
-Wformat=2
#    -Wformat-nonliteral
#         Warn about format strings that are not literals
#    -Wformat-security
#         Warn about possible security problems with format functions
#    -Wformat-y2k
#         Warn about strftime formats yielding 2-digit years
-Wframe-larger-than=<number>
#     Warn if a function's stack frame requires more than <number> bytes
-Wimport # IGNORED switch
-Winline
#     Warn when an inlined function cannot be inlined
-Winvalid-pch
#     Warn about PCH files that are found but not used
-Wjump-misses-init
#     Warn when a jump misses a variable initialization
-Wlarger-than=<number>
#     Warn if an object is larger than <number> bytes
-Wliteral-suffix
#     Warn when a string or character literal is followed by a ud-suffix which does not begin with an underscore.
-Wlogical-op
#     Warn when a logical operator is suspiciously always evaluating to true or false
-Wmissing-declarations
#     Warn about global functions without previous declarations
-Wmissing-include-dirs
#     Warn about user-specified include directories that do not exist
-Wmissing-prototypes
#     Warn about global functions without prototypes
-Wmultichar
#     Warn about use of multi-character character constants
-Wnested-externs
#     Warn about \"extern\" declarations not at file scope
-Wnoexcept
#     Warn when a noexcept expression evaluates to false even though the expression can't actually throw
-Wnon-virtual-dtor
#     Warn about non-virtual destructors
-Wnormalized=<id|nfc|nfkc>
#     Warn about non-normalised Unicode strings
-Wold-style-cast
#     Warn if a C-style cast is used in a program
-Wold-style-definition
#     Warn if an old-style parameter definition is used
-Woverloaded-virtual
#     Warn about overloaded virtual function names
-Wpacked
#     Warn when the packed attribute has no effect on struct layout
-Wpadded
#     Warn when padding is required to align structure members
-Wpedantic
#     Issue warnings needed for strict compliance to the standard
#    -Wmain
#         Warn about suspicious declarations of \"main\"
#    -Woverlength-strings
#         Warn if a string is longer than the maximum portable length specified by the standard
#    -Wpointer-sign
#         Warn when a pointer differs in signedness in an assignment
-Wpointer-arith
#     Warn about function pointer arithmetic
-Wredundant-decls
#     Warn about multiple declarations of the same object
-Wselector
#     Warn if a selector has multiple methods
-Wshadow
#     Warn when one local variable shadows another
-Wsign-promo
#     Warn when overload promotes from unsigned to signed
-Wstack-protector
#     Warn when not issuing stack smashing protection for some reason
-Wstack-usage=
#     Warn if stack usage might be larger than specified amount
-Wstrict-aliasing
#     Warn about code which might break strict aliasing rules
-Wstrict-aliasing=
#     Warn about code which might break strict aliasing rules
-Wstrict-null-sentinel
#     Warn about uncasted NULL used as sentinel
-Wstrict-overflow
#     Warn about optimizations that assume that signed overflow is undefined
-Wstrict-overflow=
#     Warn about optimizations that assume that signed overflow is undefined
-Wstrict-prototypes
#     Warn about unprototyped function declarations
-Wstrict-selector-match
#     Warn if type signatures of candidate methods do not match exactly
-Wsuggest-attribute=const
#     Warn about functions which might be candidates for __attribute__((const))
-Wsuggest-attribute=format
#     Warn about functions which might be candidates for format attributes
-Wsuggest-attribute=noreturn
#     Warn about functions which might be candidates for __attribute__((noreturn))
-Wsuggest-attribute=pure
#     Warn about functions which might be candidates for __attribute__((pure))
-Wswitch-default
#     Warn about enumerated switches missing a \"default:\" statement
-Wswitch-enum
#     Warn about all enumerated switches missing a specific case
-Wsynth
#     Deprecated.  This switch has no effect
-Wsystem-headers
#     Do not suppress warnings from system headers
-Wtraditional
#     Warn about features not present in traditional C
-Wtraditional-conversion
#     Warn of prototypes causing type conversions different from what would happen in the absence of prototype
-Wtrampolines
#     Warn whenever a trampoline is generated
-Wtrigraphs
#     Warn if trigraphs are encountered that might affect the meaning of the program
-Wundeclared-selector
#     Warn about @selector()s without previously declared methods
-Wundef
#     Warn if an undefined macro is used in an #if directive
-Wunreachable-code # IGNORED switch
#     Does nothing. Preserved for backward compatibility.
-Wunsafe-loop-optimizations
#     Warn if the loop cannot be optimized due to nontrivial assumptions.
-Wunsuffixed-float-constants
#     Warn about unsuffixed float constants
-Wunused-macros
#     Warn about macros defined in the main file that are not used
-Wuseless-cast
#     Warn about useless casts
-Wvector-operation-performance
#     Warn when a vector operation is compiled outside the SIMD
-Wwrite-strings
#     In C++, nonzero means warn about deprecated conversion from string literals to 'char *'.  In C, similar warning, except that the conversion is of course not deprecated by the ISO C standard.
-Wzero-as-null-pointer-constant
#     Warn when a literal '0' is used as null pointer