path: root/src/warnings.hpp

// no include guards
// This is the first file in every compilation, passed by the makefile.
// This file contains only preprocessor directions.

// This file is currently targeted at:
// GCC 4.6 (incomplete due to bugs)
// GCC 4.7 (for few minor workarounds)
// GCC 4.8 (zarro boogs found)
// clang 3.1 (may ICE later)
// clang 3.2 (with a few major workarounds)

// List of warnings that require arguments,
// and thus cannot reliably be activated:
//  gcc 4.6:
//      -Wlarger-than=<1024>
//      -Wnormalized=<id|nfc|nfd>
//      -Wsuggest-attribute=<noreturn,const,pure,format>
//  gcc 4.7:
//      -Wstack-usage=<8192>
//  ???
//      -Wstrict-aliasing=<1>
//      -Wstrict-overflow=<1>

// options that enable other options
// only warnings so I can catch the errors
#pragma GCC diagnostic warning "-Wall"
#pragma GCC diagnostic warning "-Wextra"
#pragma GCC diagnostic warning "-Wunused"
#pragma GCC diagnostic warning "-Wformat"

#ifdef __clang__
# if __clang_major__ < 3
#  error "your clang is way too old"
# elif __clang_major__ == 3
#  if __clang_minor__ < 1
#   error "your clang is too old"
#  endif // __clang_minor__
# endif // __clang_major__
#else // __clang__
# if __GNUC__ < 4
#  error "your gcc is way too old"
#  if __GNUC_MINOR__ < 6
#   error "your gcc is too old"
#  elif __GNUC_MINOR__ == 6
#   if __GNUC_PATCHLEVEL__ < 3
#    error "TODO: test this patchlevel"
#   endif // __GNUC_PATCHLEVEL__
#  elif __GNUC_MINOR__ == 7
#   if __GNUC_PATCHLEVEL__ < 2
#    error "your gcc has a known bad patchlevel"
#   endif // __GNUC_PATCHLEVEL__
#  endif // __GNUC_MINOR__
# endif // __GNUC__
#endif // __clang__

// BEGIN Macros to make my life easier

// stringification requirement - #sw within #ar
#define P(ar) _Pragma(#ar)

// Use "GCC diagnostic" for warnings applicable to all versions.
#define I(sw) P(GCC diagnostic ignored #sw)
#define W(sw) P(GCC diagnostic warning #sw)
#define E(sw) P(GCC diagnostic error #sw)
// configurable thing (also change in clang below!)
#define X(sw) I(sw)


#ifdef __clang__

// Use "clang diagnostic" for warnings specific to clang
# define IC(sw) P(clang diagnostic ignored #sw)
# define WC(sw) P(clang diagnostic warning #sw)
# define EC(sw) P(clang diagnostic error #sw)
# define XC(sw) IC(sw) // this is below

// warning specific to gcc
# define IG(sw) static_assert('I', #sw "skipped for clang");
# define WG(sw) static_assert('W', #sw "skipped for clang");
# define EG(sw) static_assert('E', #sw "skipped for clang");
# define XG(sw) static_assert('X', #sw "skipped for clang");

# define IG47(sw) static_assert('I', #sw "only for gcc 4.7+");
# define WG47(sw) static_assert('W', #sw "only for gcc 4.7+");
# define EG47(sw) static_assert('E', #sw "only for gcc 4.7+");
# define XG47(sw) static_assert('X', #sw "only for gcc 4.7+");

# define IG48(sw) static_assert('I', #sw "only for gcc 4.8+");
# define WG48(sw) static_assert('W', #sw "only for gcc 4.8+");
# define EG48(sw) static_assert('E', #sw "only for gcc 4.8+");
# define XG48(sw) static_assert('X', #sw "only for gcc 4.8+");

# define I47(sw) I(sw)
# define W47(sw) W(sw)
# define E47(sw) E(sw)
# define X47(sw) X(sw)

# define I48(sw) I(sw)
# define W48(sw) W(sw)
# define E48(sw) E(sw)
# define X48(sw) X(sw)

#else

// warnings specific to clang
# define IC(sw) static_assert('I', #sw "skipped for gcc");
# define WC(sw) static_assert('W', #sw "skipped for gcc");
# define EC(sw) static_assert('E', #sw "skipped for gcc");
# define XC(sw) static_assert('X', #sw "skipped for gcc");

// warnings specific to gcc
# define IG(sw) I(sw)
# define WG(sw) W(sw)
# define EG(sw) E(sw)
# define XG(sw) X(sw)

// used both for warnings not implemented in a version
// and for warnings that falsely trigger
# if __GNUC__ == 4
#  if __GNUC_MINOR__ >= 7
#   define IG47(sw) IG(sw)
#   define WG47(sw) WG(sw)
#   define EG47(sw) EG(sw)
#   define XG47(sw) XG(sw)

#   define I47(sw) I(sw)
#   define W47(sw) W(sw)
#   define E47(sw) E(sw)
#   define X47(sw) X(sw)
#  else
#   define IG47(sw) static_assert('I', #sw "only for gcc 4.7+");
#   define WG47(sw) static_assert('W', #sw "only for gcc 4.7+");
#   define EG47(sw) static_assert('E', #sw "only for gcc 4.7+");
#   define XG47(sw) static_assert('X', #sw "only for gcc 4.7+");

#   define I47(sw) static_assert('I', #sw "only for gcc 4.7+ or clang");
#   define W47(sw) static_assert('W', #sw "only for gcc 4.7+ or clang");
#   define E47(sw) static_assert('E', #sw "only for gcc 4.7+ or clang");
#   define X47(sw) static_assert('X', #sw "only for gcc 4.7+ or clang");
#  endif // __GNUC_MINOR__
#  if __GNUC_MINOR__ >= 8
#   define IG48(sw) IG(sw)
#   define WG48(sw) WG(sw)
#   define EG48(sw) EG(sw)
#   define XG48(sw) XG(sw)

#   define I48(sw) IG(sw)
#   define W48(sw) WG(sw)
#   define E48(sw) EG(sw)
#   define X48(sw) XG(sw)
#  else
#   define IG48(sw) static_assert('I', #sw "only for gcc 4.8+");
#   define WG48(sw) static_assert('W', #sw "only for gcc 4.8+");
#   define EG48(sw) static_assert('E', #sw "only for gcc 4.8+");
#   define XG48(sw) static_assert('X', #sw "only for gcc 4.8+");

#   define I48(sw) static_assert('I', #sw "only for gcc 4.8+ or clang");
#   define W48(sw) static_assert('W', #sw "only for gcc 4.8+ or clang");
#   define E48(sw) static_assert('E', #sw "only for gcc 4.8+ or clang");
#   define X48(sw) static_assert('X', #sw "only for gcc 4.8+ or clang");
#  endif // __GNUC_MINOR__
# endif // __GNUC__
#endif // __clang__

// END macros to make my life easier


/// Warn about things that will change when compiling
/// with an ABI-compliant compiler
I(-Wabi)

/// Warn if a subobject has an abi_tag attribute that
/// the complete object type does not have
WG48(-Wabi-tag)

/// Warn about suspicious uses of memory addresses
E(-Waddress)

/// Warn about returning structures, unions or arrays
I(-Waggregate-return)

/// Warn if an array is accessed out of bounds
E(-Warray-bounds)

/// Warn about inappropriate attribute usage
E(-Wattributes)

/// Warn when a built-in preprocessor macro is
// undefined or redefined
E(-Wbuiltin-macro-redefined)

/// Warn about C++ constructs whose meaning differs
/// between ISO C++ 1998 and ISO C++ 2011
// This has gone funky lately. It probably doesn't do anything anyway.
//E(-Wc++0x-compat)
//W(-Wc++11-compat)

/// Warn about pointer casts which increase alignment
X(-Wcast-align)

/// Warn about casts which discard qualifiers
E(-Wcast-qual)

/// Warn about subscripts whose type is "char"
E(-Wchar-subscripts)

/// Warn about variables that might be changed by
/// "longjmp" or "vfork"
EG(-Wclobbered)

/// Warn about possibly nested block comments, and
/// C++ comments spanning more than one physical line
E(-Wcomment)

// A fixable difference between c++11 and c++14
#if (defined(__clang__)) && __has_warning("-Wconstexpr-not-const")
EC(-Wconstexpr-not-const)
#else
static_assert('?', "-Wconstexpr-not-const not in this version")
#endif

/// Warn for implicit type conversions that may
/// change a value
X(-Wconversion)

/// Warn for converting NULL from/to a non-pointer
/// type
E(-Wconversion-null)

/// Warn in case profiles in -fprofile-use do not
/// match
WG(-Wcoverage-mismatch)

///
XC(-Wcovered-switch-default)

/// Warn when a #warning directive is encountered
WG(-Wcpp)

/// Warn when all constructors and destructors are
/// private
E(-Wctor-dtor-privacy)

/// Warn about deleting polymorphic objects with non-
/// virtual destructors
E47(-Wdelete-non-virtual-dtor)

/// Warn if a deprecated compiler feature, class,
/// method, or field is used
W(-Wdeprecated)

/// Warn about uses of __attribute__((deprecated))
/// declarations
W(-Wdeprecated-declarations)
#ifdef QUIET
I(-Wdeprecated-declarations)
#endif

/// Warn when an optimization pass is disabled
W(-Wdisabled-optimization)

/// Warn about compile-time integer division by zero
E(-Wdiv-by-zero)

///
WC(-Wdocumentation)

/// Warn about implicit conversions from "float" to
/// "double"
IG(-Wdouble-promotion)

/// Warn about violations of Effective C++ style rules
I(-Weffc++)

/// Warn about an empty body in an if or else
/// statement
E(-Wempty-body)

/// Warn about stray tokens after #elif and #endif
E(-Wendif-labels)

/// Warn about comparison of different enum types
E(-Wenum-compare)

///
EC(-Wextra-semi)

/// Warn if testing floating point numbers for
/// equality
E(-Wfloat-equal)

/// Warn about printf/scanf/strftime/strfmon format
/// string anomalies
// see below
EG(-Wformat)
// but gcc 4.8 warns on %ms, since we enabled -Wpedantic.
WG48(-Wformat)

/// Warn about format strings that contain NUL bytes
EG(-Wformat-contains-nul)

/// Warn if passing too many arguments to a function
/// for its format string
E(-Wformat-extra-args)

/// Warn about format strings that are not literals
EG(-Wformat-nonliteral)
// Available in clang, but not smart enough to handle constexpr.
IC(-Wformat-nonliteral)

/// Warn about possible security problems with format
/// functions
EG(-Wformat-security)
// Same.
IC(-Wformat-security)

/// Warn about strftime formats yielding 2-digit years
E(-Wformat-y2k)

/// Warn about zero-length formats
I(-Wformat-zero-length)

/// Warn when attempting to free a non-heap object
EG47(-Wfree-nonheap-object)

// -Wgnu is a clang alias for -Wpedantic

/// Warn whenever type qualifiers are ignored.
E(-Wignored-qualifiers)

///
EC(-Wimplicit-fallthrough)

/// Warn about C++11 inheriting constructors when the
/// base has a variadic constructor
WG48(-Winherited-variadic-ctor)

/// Warn about variables which are initialized to
/// themselves
E(-Winit-self)

/// Warn when an inlined function cannot be inlined
X(-Winline)

/// Warn when there is a cast to a pointer from an
/// integer of a different size
E(-Wint-to-pointer-cast)

/// Warn when an atomic memory model parameter is
/// known to be outside the valid range.
WG47(-Winvalid-memory-model)

/// Warn about invalid uses of the "offsetof" macro
E(-Winvalid-offsetof)

/// Warn about PCH files that are found but not used
E(-Winvalid-pch)

/// Warn when a string or character literal is
/// followed by a ud-suffix which does not begin with
/// an underscore.
WG48(-Wliteral-suffix)

/// Warn when a logical operator is suspiciously
/// always evaluating to true or false
WG(-Wlogical-op)

/// Do not warn about using "long long" when -pedantic
I(-Wlong-long)

/// Warn about suspicious declarations of "main"
E(-Wmain)

/// Warn about maybe uninitialized automatic variables
EG47(-Wmaybe-uninitialized)

/// Warn about possibly missing braces around
/// initializers
// beware of things like std::array!
E(-Wmissing-braces)

/// Warn about global functions without previous
/// declarations
// This doesn't work for clang, it wants -Wmissing-prototypes instead.
E(-Wmissing-declarations)

/// Warn about missing fields in struct initializers
// Actually supported by GCC, but gives warnings when I don't want, e.g.:
// Foo foo = {};
EC(-Wmissing-field-initializers)
IG(-Wmissing-field-initializers)

/// Warn about functions which might be candidates
/// for format attributes
E(-Wmissing-format-attribute)

/// Warn about user-specified include directories
/// that do not exist
E(-Wmissing-include-dirs)

/// Warn about functions which might be candidates
/// for __attribute__((noreturn))
W(-Wmissing-noreturn)

// clang uses this instead of -Wmissing-declarations
EC(-Wmissing-prototypes)

///
// like -Wmissing-declarations but for variables instead of functions
EC(-Wmissing-variable-declarations)

/// Warn about constructs not instrumented by
/// -fmudflap
EG(-Wmudflap)

/// Warn about use of multi-character character
/// constants
E(-Wmultichar)

/// Warn about narrowing conversions within { } that
/// are ill-formed in C++11
EG47(-Wnarrowing)

/// Warn when a noexcept expression evaluates to
/// false even though the expression can't actually
/// throw
WG(-Wnoexcept)

/// Warn when non-templatized friend functions are
/// declared within a template
EG(-Wnon-template-friend)

/// Warn about non-virtual destructors
E(-Wnon-virtual-dtor)

/// Warn about NULL being passed to argument slots
/// marked as requiring non-NULL
E(-Wnonnull)

///
XC(-Wnull-conversion)

/// Warn if a C-style cast is used in a program
E(-Wold-style-cast)

/// Warn about overflow in arithmetic expressions
W(-Woverflow)

/// Warn if a string is longer than the maximum
/// portable length specified by the standard
//X(-Woverlength-strings)

/// Warn about overloaded virtual function names
E(-Woverloaded-virtual)

/// Warn when the packed attribute has no effect on
/// struct layout
E(-Wpacked)

/// Warn about packed bit-fields whose offset changed
/// in GCC 4.4
WG(-Wpacked-bitfield-compat)

/// Warn when padding is required to align structure
/// members
I(-Wpadded)

/// Warn about possibly missing parentheses
E(-Wparentheses)

/// Issue warnings needed for strict compliance to
/// the standard
EG48(-Wpedantic)
// a bit too noisy
XC(-Wpedantic)

/// Warn when converting the type of pointers to
/// member functions
EG(-Wpmf-conversions)

/// Warn about function pointer arithmetic
E(-Wpointer-arith)

/// Warn about misuses of pragmas
EG(-Wpragmas)

/// Warn about multiple declarations of the same
/// object
W(-Wredundant-decls)

/// Warn when the compiler reorders code
E(-Wreorder)

/// Warn about returning a pointer/reference to a
/// local or temporary variable.
WG48(-Wreturn-local-addr)

/// Warn whenever a function's return type defaults
/// to "int" (C), or about inconsistent return types
/// (C++)
E(-Wreturn-type)

/// Warn about possible violations of sequence point
/// rules
E(-Wsequence-point)

/// Warn when one local variable shadows another
E(-Wshadow)

/// Warn about signed-unsigned comparisons
X(-Wsign-compare)

/// Warn when overload promotes from unsigned to
/// signed
X(-Wsign-promo)

/// This switch lacks documentation
WG48(-Wsizeof-pointer-memaccess)

/// Warn when not issuing stack smashing protection
/// for some reason
X(-Wstack-protector)

/// Warn about code which might break strict aliasing
/// rules
E(-Wstrict-aliasing)

/// Warn about uncasted NULL used as sentinel
WG(-Wstrict-null-sentinel)

/// Warn about optimizations that assume that signed
/// overflow is undefined
X(-Wstrict-overflow)

/// Warn about enumerated switches, with no default,
/// missing a case
X(-Wswitch)

/// Warn about enumerated switches missing a
/// "default:" statement
X(-Wswitch-default)

/// Warn about all enumerated switches missing a
/// specific case
X(-Wswitch-enum)

/// Warn when __sync_fetch_and_nand and
/// __sync_nand_and_fetch built-in functions are used
WG(-Wsync-nand)

/// Warn whenever a trampoline is generated
EG(-Wtrampolines)

/// Warn if trigraphs are encountered that might
/// affect the meaning of the program
E(-Wtrigraphs)

/// Warn if a comparison is always true or always
/// false due to the limited range of the data type
E(-Wtype-limits)

/// Warn if an undefined macro is used in an #if
/// directive
E(-Wundef)

/// Warn about uninitialized automatic variables
E(-Wuninitialized)

/// Warn about unrecognized pragmas
E(-Wunknown-pragmas)

///
// Not an error because of some remaining enum+default
WC(-Wunreachable-code)

/// Warn if the loop cannot be optimized due to
/// nontrivial assumptions.
XG(-Wunsafe-loop-optimizations)

/// Warn when a function parameter is only set,
/// otherwise unused
EG(-Wunused-but-set-parameter)

/// Warn when a variable is only set, otherwise unused
EG(-Wunused-but-set-variable)

/// Warn when a function is unused
E(-Wunused-function)

/// Warn when a label is unused
E(-Wunused-label)

/// Warn when typedefs locally defined in a function
/// are not used
EG47(-Wunused-local-typedefs)

/// Warn about macros defined in the main file that
/// are not used
W(-Wunused-macros)

/// Warn when a function parameter is unused
E(-Wunused-parameter)

/// Warn if a caller of a function, marked with
/// attribute warn_unused_result, does not use its
/// return value
W(-Wunused-result)

/// Warn when an expression value is unused
E(-Wunused-value)

/// Warn when a variable is unused
E(-Wunused-variable)

/// Warn about useless casts
EG48(-Wuseless-cast)

/// Warn about questionable usage of the macros used
/// to retrieve variable arguments
EG48(-Wvarargs)

/// Warn about using variadic macros
W(-Wvariadic-macros)

/// Warn when a vector operation is compiled
/// outside the SIMD
WG47(-Wvector-operation-performance)

/// Warn if a virtual base has a non-trivial move
/// assignment operator
EG48(-Wvirtual-move-assign)

/// Warn if a variable length array is used
I(-Wvla)

/// Warn when a register variable is declared volatile
E(-Wvolatile-register-var)

/// 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.
E(-Wwrite-strings)

/// Warn when a literal '0' is used as null
/// pointer
XG47(-Wzero-as-null-pointer-constant)


// clean up after myself
#undef P

#undef I
#undef W
#undef E
#undef X

#undef IC
#undef WC
#undef EC
#undef XC

#undef IG
#undef WG
#undef EG
#undef XG

#undef IG47
#undef WG47
#undef EG47
#undef XG47

#undef IG48
#undef WG48
#undef EG48
#undef XG48

#undef I47
#undef W47
#undef E47
#undef X47

#undef I48
#undef W48
#undef E48
#undef X48