Merge pull request MicrosoftDocs#5552 from Rastaban/docs-editor/compiler-warnings-c4200-throug-1713469625

v-dirichards · web-flow · commit 75297bccf846 · 2024-04-22T16:35:10.000-05:00
Update compiler-warnings-c4200-through-c4399.md
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-c4355.md b/docs/error-messages/compiler-warnings/compiler-warning-c4355.md
@@ -1,20 +1,19 @@
 ---
-description: "Learn more about: Compiler Warning C4355"
-title: "Compiler Warning C4355"
+description: "Learn more about: Compiler Warning (level 1 and level 4, off) C4355"
+title: "Compiler Warning (level 1 and level 4, off) C4355"
 ms.date: "11/04/2016"
 f1_keywords: ["C4355"]
 helpviewer_keywords: ["C4355"]
-ms.assetid: b819ecab-8a07-42d7-8fa4-1180d51626c0
 ---
-# Compiler Warning C4355
+# Compiler Warning (level 1 and level 4, off) C4355
 
-'this' : used in base member initializer list
+> '`this`': used in base member initializer list
 
-The **`this`** pointer is valid only within nonstatic member functions. It cannot be used in the initializer list for a base class.
+The `this` pointer is valid only within nonstatic member functions. It can't be used in the initializer list for a base class.
 
-The base-class constructors and class member constructors are called before **`this`** constructor. In effect, you've passed a pointer to an unconstructed object to another constructor. If those other constructors access any members or call member functions on this, the result will be undefined. You should not use the **`this`** pointer until all construction has completed.
+The base-class constructors and class member constructors are called before `this` constructor. This pattern is the same as passing a pointer to an unconstructed object to another constructor. If those other constructors access any members or call member functions on `this`, the result is undefined. You shouldn't use the `this` pointer until all construction is complete.
 
-This warning is off by default. See [Compiler Warnings That Are Off by Default](../../preprocessor/compiler-warnings-that-are-off-by-default.md) for more information.
+This warning is off by default. For more information, see [Compiler Warnings That Are Off by Default](../../preprocessor/compiler-warnings-that-are-off-by-default.md).
 
 The following sample generates C4355:
 
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4218.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4218.md
@@ -1,16 +1,15 @@
 ---
-description: "Learn more about: Compiler Warning (level 1) C4218"
-title: "Compiler Warning (level 1) C4218"
+description: "Learn more about: Compiler Warning (level 4) C4218"
+title: "Compiler Warning (level 4) C4218"
 ms.date: "11/04/2016"
 f1_keywords: ["C4218"]
 helpviewer_keywords: ["C4218"]
-ms.assetid: d6c3cd90-4518-49e9-ae86-4ba9e2761d98
 ---
-# Compiler Warning (level 1) C4218
+# Compiler Warning (level 4) C4218
 
-nonstandard extension used : must specify at least a storage class or a type
+> nonstandard extension used: must specify at least a storage class or a type
 
-With the default Microsoft extensions (/Ze), you can declare a variable without specifying a type or storage class. The default type is **`int`**.
+With the default Microsoft extensions (`/Ze`), you can declare a variable without specifying a type or storage class. The default type is **`int`**.
 
 ## Example
 
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4229.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4229.md
@@ -1,14 +1,13 @@
 ---
-description: "Learn more about: Compiler Warning (level 1) C4229"
-title: "Compiler Warning (level 1) C4229"
+description: "Learn more about: Compiler Warning (level 1, Error) C4229"
+title: "Compiler Warning (level 1, Error) C4229"
 ms.date: "11/04/2016"
 f1_keywords: ["C4229"]
 helpviewer_keywords: ["C4229"]
-ms.assetid: aadfc83b-1e5f-4229-bd0a-9c10a5d13182
 ---
-# Compiler Warning (level 1) C4229
+# Compiler Warning (level 1, Error) C4229
 
-anachronism used : modifiers on data are ignored
+> anachronism used: modifiers on data are ignored
 
 Using a Microsoft modifier such as **`__cdecl`** on a data declaration is an outdated practice.
 
@@ -17,5 +16,5 @@ Using a Microsoft modifier such as **`__cdecl`** on a data declaration is an out
 ```cpp
 // C4229.cpp
 // compile with: /W1 /LD
-int __cdecl counter;   // C4229 cdecl ignored
+int __cdecl counter;   // C4229
 ```
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4251.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4251.md
@@ -1,11 +1,11 @@
 ---
-description: "Learn more about: Compiler Warning (level 1) C4251"
-title: "Compiler Warning (level 1) C4251"
+description: "Learn more about: Compiler Warning (level 2) C4251"
+title: "Compiler Warning (level 2) C4251"
 ms.date: 12/01/2023
 f1_keywords: ["C4251"]
 helpviewer_keywords: ["C4251"]
 ---
-# Compiler Warning (level 1) C4251
+# Compiler Warning (level 2) C4251
 
 > '*type*' : class '*type1*' needs to have dll-interface to be used by clients of class '*type2*'
 
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4305.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4305.md
@@ -1,13 +1,13 @@
 ---
-description: "Learn more about: Compiler Warning (level 1) C4305"
-title: "Compiler Warning (level 1) C4305"
+description: "Learn more about: Compiler Warning (level 1 and level 2 and level 4) C4305"
+title: "Compiler Warning (level 1 and level 2 and level 4) C4305"
 ms.date: "01/17/2018"
 f1_keywords: ["C4305"]
 helpviewer_keywords: ["C4305"]
 ---
 # Compiler Warning (level 1) C4305
 
-> '*context*' : truncation from '*type1*' to '*type2*'
+> '*conversion*': truncation from '*type1*' to '*type2*'
 
 ## Remarks
 
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4329.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4329.md
@@ -4,13 +4,12 @@ title: "Compiler Warning (level 1) C4329"
 ms.date: "11/04/2016"
 f1_keywords: ["C4329"]
 helpviewer_keywords: ["C4329"]
-ms.assetid: 4316f51a-2c56-4b3f-831e-65d24b83b65c
 ---
 # Compiler Warning (level 1) C4329
 
-__declspec(align()) is ignored on enum
+> alignment specifier is ignored on enum
 
-Use of the [align](../../cpp/align-cpp.md) keyword of the [__declspec](../../cpp/declspec.md) modifier is not allowed on an **`enum`**. The following sample generates C4329:
+Use of the alignment specifiers on `enum` isn't allowed. This pattern includes the use of the [`align`](../../cpp/align-cpp.md) [`__declspec`](../../cpp/declspec.md) modifier. The following sample generates C4329:
 
 ```cpp
 // C4329.cpp
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4384.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4384.md
@@ -4,13 +4,17 @@ title: "Compiler Warning (level 1) C4384"
 ms.date: "11/04/2016"
 f1_keywords: ["C4384"]
 helpviewer_keywords: ["C4384"]
-ms.assetid: fafa8eb2-cbfc-4edb-8b0f-511ff5d37ac0
 ---
 # Compiler Warning (level 1) C4384
 
-\#pragma 'make_public' should only be used at global scope
+> `#pragma` '*pragma_name*' should only be used at global scope
 
-The [make_public](../../preprocessor/make-public.md) pragma was applied incorrectly.
+A `pragma` directive that must be applied at a global scope, was found in a different scope.
+
+The warning applies to the following `pragma` directives:
+* [`detect_mismatch`](../../preprocessor/detect-mismatch.md)
+* `extern_absolute`
+* [`make_public`](../../preprocessor/make-public.md)
 
 ## Example
 
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4265.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4265.md
@@ -7,7 +7,7 @@ helpviewer_keywords: ["C4265"]
 ---
 # Compiler Warning (level 3, off) C4265
 
-> 'class' : class has virtual functions, but destructor is not virtual
+> '*classname*': class has virtual functions, but its non-trivial destructor is not virtual; instances of this class may not be destructed correctly
 
 When a class has virtual functions but a nonvirtual destructor, objects of the type might not be destroyed properly when the class is destroyed through a base class pointer.
 
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4306.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4306.md
@@ -1,15 +1,14 @@
 ---
-description: "Learn more about: Compiler Warning (level 3) C4306"
-title: "Compiler Warning (level 3) C4306"
+description: "Learn more about: Compiler Warning (level 4) C4306"
+title: "Compiler Warning (level 4) C4306"
 ms.date: "08/27/2018"
 f1_keywords: ["C4306"]
 helpviewer_keywords: ["C4306"]
-ms.assetid: 5b2192d7-402d-4b6d-8619-08105e7dcac7
 ---
-# Compiler Warning (level 3) C4306
+# Compiler Warning (level 4) C4306
 
-> '*identifier*' : conversion from '*type1*' to '*type2*' of greater size
+> '*conversion*': conversion from '*type1*' to '*type2*' of greater size
 
-The identifier is type cast to a larger pointer. The unfilled high bits of the new type will be zero-filled.
+The identifier is type cast to a larger pointer. The unfilled high bits of the new type are zero-filled.
 
 This warning may indicate an unwanted conversion. The resulting pointer may not be valid.
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4310.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4310.md
@@ -1,13 +1,13 @@
 ---
 description: "Learn more about: Compiler Warning (level 4) C4310"
-title: "Compiler Warning (level 3) C4310"
+title: "Compiler Warning (level 4) C4310"
 ms.date: 10/17/2023
 f1_keywords: ["C4310"]
 helpviewer_keywords: ["C4310"]
 ---
 # Compiler Warning (level 4) C4310
 
-cast truncates constant value
+> cast truncates constant value
 
 A constant value is cast to a smaller type. The compiler performs the cast, which truncates data. The following sample generates C4310:
 
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4233.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4233.md
@@ -1,19 +1,14 @@
 ---
-description: "Learn more about: Compiler Warning (level 4) C4233"
-title: "Compiler Warning (level 4) C4233"
+description: "Learn more about: Compiler Warning (level 1, Error) C4233"
+title: "Compiler Warning (level 1, Error) C4233"
 ms.date: "10/25/2017"
 f1_keywords: ["C4233"]
 helpviewer_keywords: ["C4233"]
-ms.assetid: 9aa51fc6-8ef3-43b5-bafb-c9333cf60de3
 ---
-# Compiler Warning (level 4) C4233
+# Compiler Warning (level 1, Error) C4233
 
-> nonstandard extension used : '*keyword*' keyword only supported in C++, not C
+> nonstandard extension used: '*keyword*' keyword only supported in C++, not C
 
 The compiler compiled your source code as C rather than C++, and you used a keyword that is only valid in C++. The compiler compiles your source file as C if the extension of the source file is .c or you use [/Tc](../../build/reference/tc-tp-tc-tp-specify-source-file-type.md).
 
-This warning is automatically promoted to an error. If you wish to modify this behavior, use [#pragma warning](../../preprocessor/warning.md). For example, to make C4233 into a level 4 warning issue, add this line to your source code file:
-
-```cpp
-#pragma warning(4:4233)
-```
+This warning is always issued as an error. Use the [warning](../../preprocessor/warning.md) pragma to disable.
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4235.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4235.md
@@ -1,21 +1,14 @@
 ---
-description: "Learn more about: Compiler Warning (level 4) C4235"
-title: "Compiler Warning (level 4) C4235"
+description: "Learn more about: Compiler Warning (level 1, Error) C4235"
+title: "Compiler Warning (level 1, Error) C4235"
 ms.date: "11/04/2016"
 f1_keywords: ["C4235"]
 helpviewer_keywords: ["C4235"]
-ms.assetid: d4214799-d62c-4674-b4e2-9e201c303303
 ---
-# Compiler Warning (level 4) C4235
+# Compiler Warning (level 1, Error) C4235
 
-nonstandard extension used : 'keyword' keyword not supported on this architecture
+> nonstandard extension used: '*keyword*' keyword not supported on this architecture
 
-The compiler does not support the keyword you used.
+The compiler doesn't support the keyword you used on the architecture your build is targeting.
 
-This warning is automatically promoted to an error. If you wish to modify this behavior, use [#pragma warning](../../preprocessor/warning.md). For example, to make C4235 into a level 2 warning, use the following line of code
-
-```cpp
-#pragma warning(2:4235)
-```
-
-in your source code file.
+This warning is always issued as an error. Use the [warning](../../preprocessor/warning.md) pragma to disable.
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4242.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4242.md
@@ -1,20 +1,19 @@
 ---
-description: "Learn more about: Compiler Warning (level 4) C4242"
-title: "Compiler Warning (level 4) C4242"
+description: "Learn more about: Compiler Warning (level 3, off) C4242"
+title: "Compiler Warning (level 3, off) C4242"
 ms.date: "11/04/2016"
 f1_keywords: ["C4242"]
 helpviewer_keywords: ["C4242"]
-ms.assetid: 8df742e1-fbf1-42f3-8e93-c0e1c222dc7e
 ---
-# Compiler Warning (level 4) C4242
+# Compiler Warning (level 3, off) C4242
 
-'identifier' : conversion from 'type1' to 'type2', possible loss of data
+> '*identifier*': conversion from '*type1*' to '*type2*', possible loss of data
 
 The types are different. Type conversion may result in loss of data. The compiler makes the type conversion.
 
-This warning is off by default. See [Compiler Warnings That Are Off by Default](../../preprocessor/compiler-warnings-that-are-off-by-default.md) for more information.
+This warning is off by default. For more information, see [Compiler Warnings That Are Off by Default](../../preprocessor/compiler-warnings-that-are-off-by-default.md).
 
-For additional information on C4242, see [Common Compiler Errors](/windows/win32/WinProg64/common-compiler-errors).
+For more information on C4242, see [Common Compiler Errors](/windows/win32/WinProg64/common-compiler-errors).
 
 The following sample generates C4242:
 
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4254.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4254.md
@@ -1,17 +1,17 @@
 ---
-description: "Learn more about: Compiler Warning (level 4) C4254"
-title: "Compiler Warning (level 4) C4254"
+description: "Learn more about: Compiler Warning (level 4, off) C4254"
+title: "Compiler Warning (level 4, off) C4254"
 ms.date: "11/04/2016"
 f1_keywords: ["C4254"]
 helpviewer_keywords: ["C4254"]
 ---
 # Compiler Warning (level 4) C4254
 
-'operator' : conversion from 'type1' to 'type2', possible loss of data
+> '*operator*': conversion from '*type1*':'*field_bits*' to '*type2*':'*field_bits*', possible loss of data
 
 A larger bit field was assigned to a smaller bit field. There could be a loss of data.
 
-This warning is off by default. See [Compiler Warnings That Are Off by Default](../../preprocessor/compiler-warnings-that-are-off-by-default.md) for more information.
+This warning is off by default. For more information, see [Compiler Warnings That Are Off by Default](../../preprocessor/compiler-warnings-that-are-off-by-default.md).
 
 The following sample generates C4254:
 
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4324.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4324.md
@@ -4,13 +4,12 @@ title: "Compiler Warning (level 4) C4324"
 ms.date: "11/04/2016"
 f1_keywords: ["C4324"]
 helpviewer_keywords: ["C4324"]
-ms.assetid: 420fa929-d9c0-40b4-8808-2d8ad3ca8090
 ---
 # Compiler Warning (level 4) C4324
 
-'struct_name' : structure was padded due to __declspec(align())
+> '*structname*': structure was padded due to alignment specifier
 
-Padding was added at the end of a structure because you specified a [__declspec(align)](../../cpp/align-cpp.md) value.
+Padding was added at the end of a structure because you specified an alignment specifier, such as [__declspec(align)](../../cpp/align-cpp.md).
 
 For example, the following code generates C4324:
 
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-levels-1-and-4-c4223.md b/docs/error-messages/compiler-warnings/compiler-warning-levels-1-and-4-c4223.md
@@ -1,13 +1,13 @@
 ---
-description: "Learn more about: Compiler Warning (levels 1 and 4) C4223"
-title: "Compiler Warning (levels 1 and 4) C4223"
+description: "Learn more about: Compiler Warning (level 1 and level 4) C4223"
+title: "Compiler Warning (level 1 and level 4) C4223"
 ms.date: "11/04/2016"
 f1_keywords: ["C4223"]
 helpviewer_keywords: ["C4223"]
 ms.assetid: 6fc44336-0250-4432-928b-fc5dbe7b7c1c
 ---
-# Compiler Warning (levels 1 and 4) C4223
+# Compiler Warning (level 1 and level 4) C4223
 
-nonstandard extension used : non-lvalue array converted to pointer
+> nonstandard extension used: non-lvalue array converted to pointer
 
-In standard C, you cannot convert a non-lvalue array to a pointer. With the default Microsoft extensions ([/Ze](../../build/reference/za-ze-disable-language-extensions.md)), you can.
+In standard C, you can't convert a nonlvalue array to a pointer. With the default Microsoft extensions ([`/Ze`](../../build/reference/za-ze-disable-language-extensions.md)), you can.
diff --git a/docs/error-messages/compiler-warnings/compiler-warning-levels-2-and-4-c4200.md b/docs/error-messages/compiler-warnings/compiler-warning-levels-2-and-4-c4200.md
@@ -1,30 +1,29 @@
 ---
-description: "Learn more about: Compiler Warning (levels 2 and 4) C4200"
-title: "Compiler Warning (levels 2 and 4) C4200"
+description: "Learn more about: Compiler Warning (level 2 and level 4) C4200"
+title: "Compiler Warning (level 2 and level 4) C4200"
 ms.date: "11/04/2016"
 f1_keywords: ["C4200"]
 helpviewer_keywords: ["C4200"]
-ms.assetid: e44d6073-937f-42b7-acc1-65e802b475c6
 ---
-# Compiler Warning (levels 2 and 4) C4200
+# Compiler Warning (level 2 and level 4) C4200
 
-nonstandard extension used : zero-sized array in struct/union
+> nonstandard extension used: zero-sized array in struct/union
 
-Indicates that a structure or union contains an array that has zero size.
-
-Declaration of a zero-sized array is a Microsoft extension. This causes a Level-2 warning when a C++ file is compiled and a Level-4 warning when a C file is compiled. C++ compilation also gives this warning: "Cannot generate copy-ctor or copy-assignment operator when UDT contains a zero-sized array." This example generates warning C4200:
+C++ only:
+> This member will be ignored by a defaulted constructor or copy/move assignment operator
+ 
+This warning indicates that a structure or union contains an array that has zero size. Declaration of a zero-sized array is a nonstandard compiler extension. This causes a Level-2 warning when a C++ file is compiled and a Level-4 warning when a C file is compiled. This example generates warning C4200:
 
 ```cpp
 // C4200.cpp
 // compile by using: cl /W4 c4200.cpp
 struct A {
+    int len;
     int a[0];  // C4200
 };
-int main() {
-}
 ```
 
-This non-standard extension is often used to interface code with external data structures that have a variable length. If this scenario applies to your code, you can disable the warning:
+This nonstandard extension is often used to interface code with external data structures that have a variable length. If this scenario applies to your code, you can disable the warning:
 
 ## Example
 
@@ -33,8 +32,7 @@ This non-standard extension is often used to interface code with external data s
 // compile by using: cl /W4 c4200a.cpp
 #pragma warning(disable : 4200)
 struct A {
+    int len;
     int a[0];
 };
-int main() {
-}
 ```
diff --git a/docs/error-messages/compiler-warnings/compiler-warnings-c4200-through-c4399.md b/docs/error-messages/compiler-warnings/compiler-warnings-c4200-through-c4399.md
