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Compiler warnings C4800 Through C5999 |
Table of Microsoft C/C++ compiler warnings C4800 through C5999. |
03/01/2023 |
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The articles in this section of the documentation explain a subset of the warning messages that are generated by the compiler.
[!INCLUDEerror-boilerplate]
| Warning | Message |
|---|---|
| Compiler warning (level 4, off) C4800 | Implicit conversion from 'type' to bool. Possible information loss |
| Compiler warning (level 1) C4803 | 'method': the raise method has a different storage class from that of the event, 'event' |
| Compiler warning (level 1) C4804 | 'operation': unsafe use of type 'bool' in operation |
| Compiler warning (level 1) C4805 | 'operation': unsafe mix of type 'type1' and type 'type2' in operation |
| Compiler warning (level 1) C4806 | 'operation': unsafe operation: no value of type 'type1' promoted to type 'type2' can equal the given constant |
| Compiler warning (level 1) C4807 | 'operation': unsafe mix of type 'type1' and signed bit field of type 'type2' |
| Compiler warning (level 1) C4808 | case 'value' is not a valid value for switch condition of type 'bool' |
| Compiler warning (level 1) C4809 | switch statement has redundant 'default' label; all possible 'case' labels are given |
| Compiler warning (level 1) C4810 | value of pragma pack(show) == n |
| Compiler warning (level 1) C4811 | value of pragma conform(forScope, show) == value |
| Compiler warning (level 1) C4812 | obsolete declaration style: please use 'new_syntax' instead |
| Compiler warning (level 1) C4813 | 'function': a friend function of a local class must have been previously declared |
| Compiler warning (level 4) C4816 | 'param': parameter has a zero-sized array which will be truncated (unless the object is passed by reference) |
| Compiler warning (level 1) C4817 | 'member': illegal use of '.' to access this member; compiler replaced with '->' |
| Compiler warning (level 1) C4819 | The file contains a character that cannot be represented in the current code page (number). Save the file in Unicode format to prevent data loss |
| Compiler warning (level 4, off) C4820 | 'bytes' bytes padding added after construct 'member_name' |
| Compiler warning (level 1) C4821 | Unable to determine Unicode encoding type, please save the file with signature (BOM) |
| Compiler warning (level 1, off) C4822 | 'member function': local class member function does not have a body |
| Compiler warning (level 3) C4823 | 'function': uses pinning pointers but unwind semantics are not enabled. Consider using /EHa |
| Compiler warning (level 2, off) C4826 | Conversion from 'type1' to 'type2' is sign-extended. This may cause unexpected runtime behavior. |
| Compiler warning (level 3) C4827 | A public 'ToString' method with 0 parameters should be marked as virtual and override |
| Compiler warning (level 1) C4829 | Possibly incorrect parameters to function main. Consider 'int main(Platform::Array<Platform::String^>^ argv)' |
| Compiler warning (level 1) C4834 | discarding return value of function with 'nodiscard' attribute |
| Compiler warning (level 1) C4835 | 'variable': the initializer for exported data will not be run until managed code is first executed in the host assembly |
| Compiler warning (level 4, off) C4837 | trigraph detected: '??character' replaced by 'character' |
| Compiler warning (level 1) C4838 | conversion from 'type_1' to 'type_2' requires a narrowing conversion |
| Compiler warning (level 3) C4839 | non-standard use of class 'type' as an argument to a variadic function |
| Compiler warning (level 4) C4840 | non-portable use of class 'type' as an argument to a variadic function |
| Compiler warning (level 4, off) C4841 | non-standard extension used: compound member designator used in offsetof |
| Compiler warning (level 4, off) C4842 | the result of 'offsetof' applied to a type using multiple inheritance is not guaranteed to be consistent between compiler releases |
| Compiler warning (level 4) C4843 | 'type1': An exception handler of reference to array or function type is unreachable, use 'type2' instead |
| Compiler warning (level 1) C4844 | 'export module module_name;' is now the preferred syntax for declaring a module interface |
| Compiler warning (level 4) C4845 | '__declspec(no_init_all)' is ignored if '`/d1initall[0 |
| Compiler warning (level 4) C4846 | 'value' is not a valid argument for '/d1initall': command-line flag ignored |
| Compiler warning (level 4) C4847 | '__declspec(no_init_all)' can only be applied to a function, a class type, or a local variable: ignored |
| Compiler warning (level 1) C4848 | support for standard attribute 'no_unique_address' in C++17 and earlier is a vendor extension |
| Compiler warning (Level 1, error) C4854 | binding dereferenced null pointer to reference has undefined behavior |
| Compiler warning (level 1, off) C4855 | implicit capture of 'this' via '[=]' is deprecated in 'version' |
| Compiler warning (level 4) C4856 | 'value' is not a valid argument for '/d1initAll:FillPattern' (value must be between 0 and 255). Command-line flag ignored |
| Compiler warning (level 1) C4857 | C++/CLI mode does not support C++ versions newer than C++17; setting language to /std:c++17 |
| Compiler warning (level 4) C4866 | compiler may not enforce left-to-right evaluation order for call to operator_name |
| Compiler warning (level 1, error) C4867 | 'function': function call missing argument list; use 'call' to create a pointer to member |
| Compiler warning (level 4) C4868 | 'file(line_number)' compiler may not enforce left-to-right evaluation order in braced initialization list |
| Compiler warning (level 2) C4872 | floating point division by zero detected when compiling the call graph for the concurrency::parallel_for_each at: 'location' |
| Compiler warning (level 1) C4880 | casting from 'const type_1' to 'type_2': casting away constness from a pointer or reference may result in undefined behavior in an amp restricted function |
| Compiler warning (level 4) C4881 | the constructor and/or the destructor will not be invoked for tile_static variable 'variable-name' |
| Compiler warning (level 1) C4882 | passing functors with non-const call operators to concurrency::parallel_for_each is deprecated |
| Compiler warning C4900 | Il mismatch between 'tool1' version 'version1' and 'tool2' version 'version2' |
| Compiler warning (level 1, off) C4905 | wide string literal cast to 'LPSTR' |
| Compiler warning (level 1, off) C4906 | string literal cast to 'LPWSTR' |
| Compiler warning (level 1) C4910 | '<identifier>: '__declspec(dllexport)' and 'extern' are incompatible on an explicit instantiation |
| Compiler warning (level 1) C4912 | 'attribute': attribute has undefined behavior on a nested UDT |
| Compiler warning (level 4) C4913 | user defined binary operator ',' exists but no overload could convert all operands, default built-in binary operator ',' used |
| Compiler warning (level 1) C4916 | in order to have a dispid, 'description': must be introduced by an interface |
| Compiler warning (level 1, off) C4917 | 'declarator': a GUID can only be associated with a class, interface or namespace |
| Compiler warning (level 4) C4918 | 'character': invalid character in pragma optimization list |
| Compiler warning (level 1) C4920 | enum enum-name member member_1=value_1 already seen in enum enum-name as member_2=value_2 |
| Compiler warning (level 3) C4921 | 'description': attribute value 'attribute' should not be multiply specified |
| Compiler warning (level 1) C4925 | 'method': dispinterface method cannot be called from script |
| Compiler warning (level 1) C4926 | 'identifier': symbol is already defined: attributes ignored |
| Compiler warning (level 1) C4927 | illegal conversion; more than one user-defined conversion has been implicitly applied |
| Compiler warning (level 1, off) C4928 | illegal copy-initialization; more than one user-defined conversion has been implicitly applied |
| Compiler warning (level 1) C4929 | 'file': typelibrary contains a union; ignoring the 'embedded_idl' qualifier |
| Compiler warning (level 1) C4930 | 'prototype': prototyped function not called (was a variable definition intended?) |
| Compiler warning (level 4, off) C4931 | we are assuming the type library was built for number-bit pointers |
| Compiler warning (level 4) C4932 | __identifier(identifier) and __identifier(identifier) are indistinguishable |
| Compiler warning (level 1) C4934 | '__delegate(multicast)' is deprecated, use '__delegate' instead |
| Compiler warning (level 1) C4935 | assembly access specifier modified from 'access' |
| Compiler warning (level 1, Error) C4936 | this __declspec is supported only when compiled with /clr or /clr:pure |
| Compiler warning (level 4) C4937 | 'text1' and 'text2' are indistinguishable as arguments to 'directive' |
| Compiler warning (level 4) C4938 | 'var': Floating point reduction variable may cause inconsistent results under /fp:strict or #pragma fenv_access |
| Compiler warning C4939 | #pragma vtordisp is deprecated and will be removed in a future release of Visual C++ |
| Compiler warning (level 1) C4944 | 'symbol': cannot import symbol from 'assembly1': as 'symbol' already exists in the current scope |
| Compiler warning (level 1) C4945 | 'symbol': cannot import symbol from 'assembly1': as 'symbol' has already been imported from another assembly 'assembly2' |
| Compiler warning (level 1, off) C4946 | reinterpret_cast used between related classes: 'class1' and 'class2' |
| Compiler warning (level 1) C4947 | 'type_or_member': marked as obsolete |
| Compiler warning (level 2) C4948 | return type of 'accessor' does not match the last parameter type of the corresponding setter |
| Compiler warning (level 1 and level 4) C4949 | pragmas 'managed' and 'unmanaged' are meaningful only when compiled with '/clr[:option]' |
| Compiler warning (level 1, Error) C4950 | 'type_or_member': marked as obsolete |
| Compiler warning (level 1) C4951 | 'function' has been edited since profile data was collected, function profile data not used |
| Compiler warning (level 1) C4952 | 'function': no profile data found in program database 'pgd-file' |
| Compiler warning (level 1) C4953 | Inlinee 'function' has been edited since profile data was collected, profile data not used |
| Compiler warning C4954 | 'function': not profiled (contains __int64 switch expression) |
| Compiler warning C4955 | 'import2': import ignored; already imported from 'import1' |
| Compiler warning (level 1, Error) C4956 | 'type': this type is not verifiable |
| Compiler warning (level 1, Error) C4957 | 'cast': explicit cast from 'cast_from' to 'cast_to' is not verifiable |
| Compiler warning (level 1, Error) C4958 | 'operation': pointer arithmetic is not verifiable |
| Compiler warning (level 1, Error) C4959 | cannot define unmanaged type 'type' in /clr:safe because accessing its members yields unverifiable code |
| Compiler warning (level 4) C4960 | 'function' is too big to be profiled |
| Compiler warning (level 1) C4961 | No profile data was merged into 'pgd-file', profile-guided optimizations disabled |
| Compiler warning (level 4, off) C4962 | 'function': Profile-guided optimizations disabled because optimizations caused profile data to become inconsistent |
| Compiler warning (level 1) C4963 | 'description': no profile data found; different compiler options were used in instrumented build |
| Compiler warning (level 1) C4964 | No optimization options were specified; profile info will not be collected |
| Compiler warning (level 1) C4965 | implicit box of integer 0; use nullptr or explicit cast |
| Compiler warning (level 1) C4966 | 'function' has __code_seg annotation with unsupported segment name, annotation ignored |
| Compiler warning C4970 | delegate constructor: target object ignored since 'type' is static |
| Compiler warning (level 1) C4971 | Argument order: <target object>, <target function> for delegate constructor is deprecated, use <target function>, <target object=""> |
| Compiler warning (level 1, Error) C4972 | Directly modifying or treating the result of an unbox operation as an lvalue is unverifiable |
| Compiler warning (level 1) C4973 | 'symbol': marked as deprecated |
| Compiler warning (level 1) C4974 | 'symbol': marked as deprecated |
| Compiler warning (level 3) C4981 | Warbird: function 'function' marked as __forceinline not inlined because it contains exception semantics |
| Compiler warning (level 3) C4983 | '/analyze:sarif:hashname' ignored because the argument to '/analyze:log' is a single file rather than a directory |
| Compiler warning C4984 | 'if constexpr' is a C++17 language extension |
| Compiler warning (level 4) C4985 | 'symbol_name': attributes not present on previous declaration. |
| Compiler warning (level 4, off) C4986 | 'declaration': exception specification does not match previous declaration |
| Compiler warning (level 4, off) C4987 | nonstandard extension used: 'throw (...)' |
| Compiler warning (level 4, off) C4988 | 'variable': variable declared outside class/function scope |
| Compiler warning (level 4) C4989 | 'type': type has conflicting definitions. |
| Compiler warning (level 3) C4990 | Warbird: message |
| Compiler warning (level 3) C4991 | Warbird: function 'function' marked as __forceinline not inlined because protection level of inlinee is greater than the parent |
| Compiler warning (level 3) C4992 | Warbird: function 'function-name' marked as __forceinline not inlined because it contains inline assembly which cannot be protected |
| Compiler warning (level 3) C4995 | 'function': name was marked as #pragma deprecated |
| Compiler warning (level 3) C4996 | 'deprecated-declaration': deprecation-message (or "was declared deprecated") |
| Compiler warning (level 1) C4997 | 'class': coclass does not implement a COM interface or pseudo-interface |
| Compiler warning (level 1) C4998 | EXPECTATION FAILED: expectation(value) |
| Compiler warning C4999 | UNKNOWN WARNING Please choose the Technical Support command on the Visual C++ Help menu, or open the Technical Support help file for more information |
| Compiler warning C5022 | 'type': multiple move constructors specified |
| Compiler warning C5023 | 'type': multiple move assignment operators specified |
| Compiler warning (level 4, off) C5024 | 'type': move constructor was implicitly defined as deleted |
| Compiler warning (level 4, off) C5025 | 'type': move assignment operator was implicitly defined as deleted |
| Compiler warning (level 1 and level 4, off) C5026 | 'type': move constructor was implicitly defined as deleted |
| Compiler warning (level 1 and level 4, off) C5027 | 'type': move assignment operator was implicitly defined as deleted |
| Compiler warning (level 1) C5028 | 'name': Alignment specified in prior declaration (number) not specified in definition |
| Compiler warning (level 4, off) C5029 | nonstandard extension used: alignment attributes in C++ apply to variables, data members and tag types only |
| Compiler warning (level 3) C5030 | attribute 'attribute-name' is not recognized |
| Compiler warning (level 4, off) C5031 | #pragma warning(pop): likely mismatch, popping warning state pushed in different file |
| Compiler warning (level 4, off) C5032 | detected #pragma warning(push) with no corresponding #pragma warning(pop) |
| Compiler warning (level 1) C5033 | 'storage-class' is no longer a supported storage class |
| Compiler warning (level 5, off) C5034 | use of intrinsic 'intrinsic' causes function function-name to be compiled as guest code |
| Compiler warning (level 5, off) C5035 | use of feature 'feature' causes function function-name to be compiled as guest code |
| Compiler warning (level 1) C5036 | varargs function pointer conversion when compiling with /hybrid:x86arm64 'type1' to 'type2' |
| Compiler warning (error) C5037 | 'member-function': an out-of-line definition of a member of a class template cannot have default arguments |
| Compiler warning (level 4, off) C5038 | data member 'member1' will be initialized after data member 'member2' |
| Compiler warning (level 4, off) C5039 | 'function': pointer or reference to potentially throwing function passed to extern C function under -EHc. Undefined behavior may occur if this function throws an exception. |
| Compiler warning (level 3) C5040 | dynamic exception specifications are valid only in C++14 and earlier; treating as noexcept(false) |
| Compiler warning (level 1, off) C5041 | 'definition': out-of-line definition for constexpr static data member is not needed and is deprecated in C++17 |
| Compiler warning (level 3, off) C5042 | 'declaration': function declarations at block scope cannot be specified 'inline' in standard C++; remove 'inline' specifier |
| Compiler warning (level 2) C5043 | 'specification': exception specification does not match previous declaration |
| Compiler warning (level 4) C5044 | An argument to command-line option option-name points to a path 'path-name' that does not exist |
| Compiler warning (level 4) C5045 | Compiler will insert Spectre mitigation for memory load if /Qspectre switch specified |
| Compiler warning (level 2) C5046 | 'function': Symbol involving type with internal linkage not defined |
| Compiler warning (level 1) C5047 | use of nonstandard __if_exists with modules is not supported |
| Compiler warning (level 1) C5048 | Use of macro 'macroname' may result in non-deterministic output |
| Compiler warning (level 1) C5049 | 'string': Embedding a full path may result in machine-dependent output |
| Compiler warning (level 1) C5050 | Possible incompatible environment while importing module 'module_name': issue |
| Compiler warning (level 1) C5051 | attribute 'attribute-name' requires at least 'standard-level'; ignored |
| Compiler warning (level 3, off) C5052 | Keyword 'keyword-name' was introduced in C++<version> and requires use of the 'option-name' command-line option |
| Compiler warning (level 1) C5053 | support for 'explicit(<expr>)' in C++17 and earlier is a vendor extension |
| Compiler warning (level 4) C5054 | operator 'operator-name': deprecated between enumerations of different types |
| Compiler warning (level 1) C5055 | operator 'operator-name': deprecated between enumerations and floating-point types |
| Compiler warning (level 1) C5056 | operator 'operator-name': deprecated for array types |
| Compiler warning (level 1) C5057 | header unit reference to 'name' already exists. Ignoring header unit 'header-name' |
| Compiler warning (level 1) C5058 | file system error: cannot find header file 'file-name' for header unit 'unit-name' |
| Compiler warning C5059 | runtime checks and address sanitizer is not currently supported - disabling runtime checks |
| Compiler warning (level 4) C5060 | /Qpar and address sanitizer not currently supported - disabling auto-parallelization |
| Compiler warning (level 4) C5061 | the use of a comma operator as a subscript expression has been deprecated |
| Compiler warning (level 4) C5062 | enum direct list initialization between 'type-1' and 'type-2' is no longer supported |
| Compiler warning (level 1) C5063 | 'std::is_constant_evaluated' always evaluates to true in manifestly constant-evaluated expressions |
| Compiler warning (level 1) C5081 | Secure hotpatch is not supported with /GENPROFILE, /FASTGENPROFILE or /LTCG:PGI, disabling secure hotpatch. |
| Compiler warning (level 1) C5100 | __VA_ARGS__ is reserved for use in variadic macros |
| Compiler warning (level 1) C5101 | use of preprocessor directive in function-like macro argument list is undefined behavior |
| Compiler warning (level 1) C5102 | ignoring invalid command-line macro definition 'value' |
| Compiler warning (level 1) C5103 | pasting 'token1' and 'token2' does not result in a valid preprocessing token |
| Compiler warning (level 1) C5104 | found 'string1#string2' in macro replacement list, did you mean 'string1""#string2'? |
| Compiler warning (level 1) C5105 | macro expansion producing 'defined' has undefined behavior |
| Compiler warning (level 1) C5106 | macro redefined with different parameter names |
| Compiler warning (level 1) C5107 | missing terminating 'char' character |
| Compiler warning (level 1) C5108 | __VA_OPT__ is reserved for use in variadic macros |
| Compiler warning (level 1) C5200 | feature 'feature-name' requires compiler flag 'option-name' |
| Compiler warning (level 1) C5201 | a module declaration can appear only at the start of a translation unit unless a global module fragment is used |
| Compiler warning (level 1) C5202 | a global module fragment can only contain preprocessor directives |
| Compiler warning (level 1) C5203 | a parenthesized declarator name after 'explicit' will be considered an explicit-specifier in C++20 |
| Compiler warning (level 3, off) C5204 | 'type-name': class has virtual functions, but its trivial destructor is not virtual; instances of objects derived from this class may not be destructed correctly |
| Compiler warning (level 4) C5205 | delete of an abstract class 'type-name' that has a non-virtual destructor results in undefined behavior |
| Compiler warning (level 3) C5206 | deduced return types for coroutines is a non-standard extension |
| Compiler warning (level 1) C5207 | the simple requirement asserts the validity of expression 'e->id'. Did you mean '{ e } -> id'? You can suppress the warning using '{ e->id }' |
| Compiler warning (level 1) C5208 | unnamed class used in typedef name cannot declare members other than non-static data members, member enumerations, or member classes |
| Compiler warning (level 1) C5209 | the C++20 syntax for an init-capture has changed to '& ...opt identifier initializer' |
| Compiler warning (level 1) C5210 | 'name' is not a valid header unit reference; ignoring |
| Compiler warning (level 1) C5212 | 'name' is not a valid named reference; treating as reference to file |
| Compiler warning (level 1) C5213 | 'name' named reference is treated as a named partition but the name is not specified; treating as reference to file |
| Compiler warning (level 4, off) C5214 | applying 'modifier' to an operand with a volatile qualified type is deprecated in C++20 |
| Compiler warning (level 4, off) C5215 | 'name' a function parameter with a volatile qualified type is deprecated in C++20 |
| Compiler warning (level 4, off) C5216 | 'name' a volatile qualified return type is deprecated in C++20 |
| Compiler warning (level 4, off) C5217 | a structured binding declaration that includes volatile is deprecated in C++20 |
| Compiler warning (level 1) C5218 | destroying delete may not behave as intended when non-conforming switches '/Zc:sizedDealloc-' or '/Zc:alignedNew-' are used |
| Compiler warning (level 2, off) C5219 | implicit conversion from 'type-1' to 'type-2', possible loss of data |
| Compiler warning (level 4, off) C5220 | 'name': a non-static data member with a volatile qualified type no longer implies that compiler generated copy/move constructors and copy/move assignment operators are not trivial |
| Compiler warning (level 1) C5221 | xfg::rename is deprecated. |
| Compiler warning (level 3) C5222 | 'attribute-name': all unscoped attribute names are reserved for future standardization |
| Compiler warning (level 3) C5223 | all attribute names in the attribute namespace 'msvc' are reserved for the implementation |
| Compiler warning (level 3) C5224 | all attribute names in the attribute namespace 'namespace-name' are reserved for future standardization |
| Compiler warning (level 1) C5225 | 'symbol': exported inline function defined in a private module fragment is a non-standard extension |
| Compiler warning (level 1) C5226 | 'symbol': exported template defined in private module fragment has no reachable instantiation |
| Compiler warning (level 4) C5227 | nonstandard extension, resolved 'symbol' to 'value' which is not visible with /permissive- on. |
| Compiler warning (level 4) C5228 | nonstandard extension, 'identifier' resolved to a member of a dependent base. This lookup is not allowed under /permissive-. |
| Compiler warning (level 4) C5229 | nonstandard extension, the hidden friend function 'function-name' was found by name lookup which isn't allowed under /permissive-. |
| Compiler warning C5230 | nonstandard extension, 'identifier' was resolved to 'symbol-1' under /permissive. Under /permissive- it would resolve to 'symbol-2'. |
| Compiler warning (level 3) C5231 | the expression 'co_await promise.final_suspend()' must be non-throwing |
| Compiler warning (level 1) C5232 | in C++20 this comparison calls 'name' recursively |
| Compiler warning (level 4, off) C5233 | explicit lambda capture 'identifier' is not used |
| Compiler warning (level 1) C5234 | file system error: 'filename' is not a valid header-name; ignoring |
| Compiler warning (level 1) C5235 | JSON parse error: message; ignoring 'filename' |
| Compiler warning (level 1) C5236 | JSON ill-formed: message; ignoring 'filename' |
| Compiler warning (level 1) C5237 | cannot resolve header unit entry 'name' to a header file in 'filename'; ignoring entry |
| Compiler warning (level 1) C5238 | file system error: cannot open 'filename' for reading; ignoring |
| Compiler warning (level 4) C5239 | 'symbol': potentially-throwing function called from a function declared __declspec(nothrow). Undefined behavior may occur if an exception is thrown. |
| Compiler warning (level 4) C5240 | 'attribute-name': attribute is ignored in this syntactic position |
| Compiler warning (level 1) C5241 | '/exportHeader' usage to lookup header-name is deprecated; prefer '/headerName:name value=filename' |
| Compiler warning (level 1) C5242 | syntax error in pragma 'identifier' |
| Compiler warning (level 1, off) C5243 | 'type-name': using incomplete class 'class-name' can cause potential one definition rule violation due to ABI limitation |
| Compiler warning (level 1) C5244 | '#include <filename>' in the purview of module 'module-name-1' appears erroneous. Consider moving that directive before the module declaration, or replace the textual inclusion with 'import <module-name-2>;'. |
| Compiler warning (level 4, off) C5245 | 'function': unreferenced function with internal linkage has been removed |
| Compiler warning (level 1, off) C5246 | 'member': the initialization of a subobject should be wrapped in braces |
| Compiler warning (level 1, off) C5247 | section 'section-name' is reserved for C++ dynamic initialization. Manually creating the section will interfere with C++ dynamic initialization and may lead to undefined behavior |
| Compiler warning (level 1, off) C5248 | section 'section-name' is reserved for C++ dynamic initialization. Variables manually put into the section may be optimized out and their order relative to compiler generated dynamic initializers is unspecified. |
| Compiler warning (level 1, off) C5249 | 'bitfield' of type 'enumeration_name' has named enumerators with values that cannot be represented in the given bit field width of 'bitfield_width'. |
| Compiler warning (level 3, off) C5250 | 'function_name': intrinsic function not declared. |
| Compiler warning (level 4, off) C5251 | segment-name changed after including header |
| Compiler warning (level 4) C5252 | Multiple different types resulted in the same XFG type-hash hash-value; the PDB will only record information for one of them |
| Compiler warning (level 4) C5253 | a non-local lambda cannot have a capture default |
| Compiler warning (level 4, off) C5254 | language feature 'terse static assert' requires compiler flag '/std:c++17' |
| Compiler warning (level 3) C5255 | unterminated bidirectional character encountered: 'U+XXXX' |
| Compiler warning (level 1, off) C5256 | 'enumeration': a non-defining declaration of an enumeration with a fixed underlying type is only permitted as a standalone declaration |
| Compiler warning (level 1 or 4) C5257 | 'enumeration': enumeration was previously declared without a fixed underlying type |
| Compiler warning (level 4, off) C5258 | explicit capture of 'symbol' is not required for this use |
| Compiler warning (level 4, off) C5259 | 'specialized-type': explicit specialization requires 'template <>' |
| Compiler warning (level 1) C5260 | the constant variable 'variable-name' has internal linkage in an included header file context, but external linkage in imported header unit context; consider declaring it 'inline' as well if it will be shared across translation units, or 'static' to express intent to use it local to this translation unit |
| Compiler warning (level 2) C5261 | no integer type can represent all enumerator values in enumeration 'enum-name' |
| Compiler warning (level 1, error, off) C5262 | implicit fall-through occurs here; are you missing a break statement? Use [[fallthrough]] when a break statement is intentionally omitted between cases |
| Compiler warning (level 4, off) C5263 | calling 'std::move' on a temporary object prevents copy elision |
| Compiler warning (level 4, off) C5264 | 'variable-name': 'const' variable is not used |
| Compiler warning (level 1, error) C5300 | '#pragma omp atomic': left operand of 'operator' must match left hand side of assignment-expression |
| Compiler warning (level 1) C5301 | '#pragma omp for': 'loop-index' increases while loop condition uses 'comparison'; non-terminating loop? |
| Compiler warning (level 1) C5302 | '#pragma omp for': 'loop-index' decreases while loop condition uses 'comparison'; non-terminating loop? |
C/C++ Compiler and build tools errors and warnings
Compiler warnings C4000 - C5999