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Microsoft C/C++ compiler (MSVC) compiler warnings C5200 through C5399 |
Table of Microsoft C/C++ compiler (MSVC) warnings C5200 through C5399. |
04/19/2024 |
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The articles in this section describe Microsoft C/C++ compiler warning messages C5200 through C5399.
[!INCLUDEerror-boilerplate]
| Warning | Message |
|---|---|
| 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, error) 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 module 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, error) 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, off) 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 | the value of #pragma pragma name changed after #include; #pragma pragma name(pop) missing in this 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 and level 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, 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) C5265 | cannot open search path 'path' |
| Compiler warning (level 4, off) C5266 | 'const' qualifier on return type has no effect |
| Compiler warning (level 4, off) C5267 | definition of implicit copy constructor/assignment operator for 'type' is deprecated because it has a user-provided assignment operator/copy constructor |
| Compiler warning (level 1) C5268 | Failed to allocate memory at fixed address 0xaddress. Use /Yb to specify a specific address base if bit-identical .pch files are required. |
| Compiler warning (level 1) C5269 | Failed to allocate PCH memory at fixed address 0xaddress. Use /Ym to specify a specific address base if bit-identical .pch files are required. |
| Compiler warning (level 3) C5270 | 'value' is not allowed for option 'switch name'; allowed values are: value list |
| Compiler warning (level 4) C5271 | previously imported assembly 'assembly1' has the same name as assembly 'assembly2' being imported. Is this intentional? |
| Compiler warning (level 1) C5272 | throwing an object of non-copyable type 'type' is non-standard. If a copy is needed at runtime it will be made as if by memcpy. |
| Compiler warning (level 1) C5273 | behavior change: _Alignas on anonymous type no longer ignored (promoted members will align) |
| Compiler warning (level 1) C5274 | behavior change: _Alignas no longer applies to the type 'type' (only applies to declared data objects) |
| Compiler warning (error) C5275 | assembly 'name' being imported under '/clr' does not contain the required fundamental types |
| Compiler warning (level 1) C5276 | /experimental:ifcDebugRecords currently requires /Z7 to be enabled. Please recompile with /Z7 enabled. |
| Compiler warning (level 1) C5277 | type trait optimization for 'class name' is disabled |
| Compiler warning (level 1) C5278 | adding a specialization for 'type' has undefined behavior |
| Compiler warning (level 1) C5279 | a lambda declarator without a parameter list requires at least 'language version' |
| Compiler warning (level 1) C5280 | a static operator 'operator name' requires at least 'language version' |
| Compiler warning (level 1) C5281 | a static lambda requires at least 'language version' |
| Compiler warning (level 1) C5282 | 'if consteval' requires at least 'language version' |
| Compiler warning (level 1) C5283 | an attribute in this position requires at least 'language version' |
| Compiler warning (level 4) C5284 | conversion from value 'value' of type 'type 1' to 'type 2' requires a narrowing conversion |
| Compiler warning (level 1) C5285 | cannot declare a specialization for 'template name': template argument |
| Compiler warning (level 1) C5286 | implicit conversion from enum type 'type 1' to enum type 'type 2'; use an explicit cast to silence this warning |
| Compiler warning (level 1) C5287 | operands are different enum types 'type 1' and 'type 2'; use an explicit cast to silence this warning |
| Compiler warning (error) C5300 | '#pragma omp atomic clause': expression mismatch for lvalue being updated |
| 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? |
| Compiler warning (level 1) C5303 | function marked with [[msvc::intrinsic]] did not result in a no-op cast |
| Compiler warning (level 1) C5304 | a declaration designated by the using-declaration 'name1' exported from this module has internal linkage and using such a name outside the module is ill-formed; consider declaring 'name2' 'inline' to use it outside of this module |
| Compiler warning (level 1) C5305 | 'name': an explicit instantiation declaration that follows an explicit instantiation definition is ignored |
| Compiler warning (level 1) C5306 | parameter array behavior change: overload 'identifier 1' resolved to 'identifier 2'; previously, it would have resolved to 'identifier 3'. Use /clr:ECMAParamArray to revert to old behavior |
| Compiler warning (level 3) C5307 | 'function': argument (argument number) converted from 'type 1' to 'type 2'. Missing 'L' encoding-prefix for character literal? |
| Compiler warning (level 1, error) C5308 | Modifying reserved macro name 'macro name' may cause undefined behavior |
| Compiler warning (level 1, error) C5309 | literal suffix 'name' requires at least 'language version' |
C/C++ Compiler and build tools errors and warnings
Compiler warnings C4000 - C5999