From 06e442d1843b58629704fb542fd5648eab7bba85 Mon Sep 17 00:00:00 2001 From: Rageking8 <106309953+Rageking8@users.noreply.github.com> Date: Wed, 27 Aug 2025 23:27:08 +0800 Subject: [PATCH 1/5] Add blockquotes for warning messages in range [C4231, C4270] --- .../compiler-warnings/compiler-warning-level-1-c4237.md | 2 +- .../compiler-warnings/compiler-warning-level-1-c4258.md | 2 +- .../compiler-warnings/compiler-warning-level-1-c4269.md | 2 +- .../compiler-warnings/compiler-warning-level-2-c4244.md | 2 +- .../compiler-warnings/compiler-warning-level-2-c4250.md | 2 +- .../compiler-warnings/compiler-warning-level-3-c4240.md | 2 +- .../compiler-warnings/compiler-warning-level-3-c4243.md | 2 +- .../compiler-warnings/compiler-warning-level-3-c4267.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4232.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4234.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4238.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4239.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4256.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4268.md | 2 +- .../compiler-warnings/compiler-warning-levels-3-and-4-c4244.md | 2 +- 15 files changed, 15 insertions(+), 15 deletions(-) diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md index 30336fc802..3f67549fb3 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md @@ -8,7 +8,7 @@ ms.assetid: f2e86c4b-80d8-460e-9429-83c5f3f5d7ca --- # Compiler Warning (level 1) C4237 -'keyword' keyword is not yet supported, but reserved for future use +> 'keyword' keyword is not yet supported, but reserved for future use A keyword in the C++ specification is not implemented in the Microsoft C++ compiler, but the keyword is not available as a user-defined symbol. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md index f2131c6a91..3904ba4c66 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md @@ -8,7 +8,7 @@ ms.assetid: bbb75e6d-6693-4e62-8ed3-b006a0ec55e3 --- # Compiler Warning (level 1) C4258 -'variable' : definition from the for loop is ignored; the definition from the enclosing scope is used" +> 'variable' : definition from the for loop is ignored; the definition from the enclosing scope is used" Under [/Ze](../../build/reference/za-ze-disable-language-extensions.md) and [/Zc:forScope](../../build/reference/zc-forscope-force-conformance-in-for-loop-scope.md), variables defined in a [for](../../cpp/for-statement-cpp.md) loop go out of scope after the **`for`** loop ends. This warning occurs if a variable with the same name as the loop variable, but defined in the enclosing loop, is used again in the scope containing the **`for`** loop. For example: diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md index faa8737853..322895fb5f 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md @@ -7,7 +7,7 @@ helpviewer_keywords: ["C4269"] --- # Compiler Warning (level 1) C4269 -'identifier' : 'const' automatic data initialized with compiler generated default constructor produces unreliable results +> 'identifier' : 'const' automatic data initialized with compiler generated default constructor produces unreliable results A **`const`** automatic instance of a non-trivial class is initialized with a compiler-generated default constructor. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md index f1b1594439..c88d6b4d73 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md @@ -8,7 +8,7 @@ ms.assetid: 2c19d157-21d1-42c2-a6c0-3f30f2ce3813 --- # Compiler Warning (level 2) C4244 -'argument' : conversion from 'type1' to 'type2', possible loss of data +> 'argument' : conversion from 'type1' to 'type2', possible loss of data A floating point type was converted to an integer type. A possible loss of data may have occurred. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md index 3ec69fa013..191ce3b1fe 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md @@ -8,7 +8,7 @@ ms.assetid: d47f7249-6b5a-414b-b2d4-56e5d246a782 --- # Compiler Warning (level 2) C4250 -'class1' : inherits 'class2::member' via dominance +> 'class1' : inherits 'class2::member' via dominance Two or more members have the same name. The one in `class2` is inherited because it is a base class for the other classes that contained this member. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md index 66fc798b05..aa98f67f45 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md @@ -8,7 +8,7 @@ ms.assetid: a2657cdb-18e1-493f-882b-4e10c0bca71d --- # Compiler Warning (level 3) C4240 -nonstandard extension used : access to 'classname' now defined to be 'access specifier', previously it was defined to be 'access specifier' +> nonstandard extension used : access to 'classname' now defined to be 'access specifier', previously it was defined to be 'access specifier' Under ANSI compatibility ([/Za](../../build/reference/za-ze-disable-language-extensions.md)), you cannot change the access to a nested class. Under the default Microsoft extensions (/Ze), you can, with this warning. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md index 8fab32eef4..1979eaf6c3 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md @@ -7,7 +7,7 @@ helpviewer_keywords: ["C4243"] --- # Compiler Warning (level 3) C4243 -'conversion type' conversion exists from 'type1' to 'type2', but is inaccessible +> 'conversion type' conversion exists from 'type1' to 'type2', but is inaccessible A pointer to a derived class is converted to a pointer to a base class, but the derived class inherits the base class with private or protected access. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md index bca3c8da4a..537027a3bb 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md @@ -8,7 +8,7 @@ ms.assetid: 2fa2f13f-fa4f-47bb-ad8f-6cb19cfc91e6 --- # Compiler Warning (level 3) C4267 -'var' : conversion from 'size_t' to 'type', possible loss of data +> 'var' : conversion from 'size_t' to 'type', possible loss of data The compiler detected a conversion from `size_t` to a smaller type. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md index 78d4e5ed20..47f53d3a3e 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md @@ -8,7 +8,7 @@ ms.assetid: f92028a5-4ddd-43c1-97f5-4f724e5e14af --- # Compiler Warning (level 4) C4232 -nonstandard extension used : 'identifier' : address of dllimport 'dllimport' is not static, identity not guaranteed +> nonstandard extension used : 'identifier' : address of dllimport 'dllimport' is not static, identity not guaranteed Under Microsoft extensions (/Ze), you can give a nonstatic value as the address of a function declared with the **`dllimport`** modifier. Under ANSI compatibility ([/Za](../../build/reference/za-ze-disable-language-extensions.md)), this causes an error. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md index 3b2bc5eacb..b0fa52b455 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md @@ -8,7 +8,7 @@ ms.assetid: f7fecd5c-8248-4fde-8446-502aedc357ca --- # Compiler Warning (level 4) C4234 -nonstandard extension used: 'keyword' keyword reserved for future use +> nonstandard extension used: 'keyword' keyword reserved for future use The compiler does not yet implement the keyword you used. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md index 679d603ef6..ac680a5ac5 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md @@ -8,7 +8,7 @@ ms.assetid: 5d4051d3-7b0f-43ea-8c8d-d194bfdceb71 --- # Compiler Warning (level 4) C4238 -nonstandard extension used : class rvalue used as lvalue +> nonstandard extension used : class rvalue used as lvalue For compatibility with previous versions of Visual C++, Microsoft extensions (**/Ze**) allow you to use a class type as an rvalue in a context that implicitly or explicitly takes its address. In some cases, such as the example below, this can be dangerous. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md index c68de7e669..3fd260094f 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md @@ -8,7 +8,7 @@ ms.assetid: a23dc16a-649e-4870-9a24-275de1584fcd --- # Compiler Warning (level 4) C4239 -nonstandard extension used : 'token' : conversion from 'type' to 'type' +> nonstandard extension used : 'token' : conversion from 'type' to 'type' This type conversion is not allowed by the C++ standard, but it is permitted here as an extension. This warning is always followed by at least one line of explanation describing the language rule being violated. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md index 8ce1d40f26..fbde6eb7d7 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md @@ -8,7 +8,7 @@ ms.assetid: a755a32e-895a-4837-a2b5-4ea06b736798 --- # Compiler Warning (level 4) C4256 -'function' : constructor for class with virtual bases has '...'; calls may not be compatible with older versions of Visual C++ +> 'function' : constructor for class with virtual bases has '...'; calls may not be compatible with older versions of Visual C++ Possible incompatibility. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md index 7ec668928d..20efbfd9a7 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md @@ -8,7 +8,7 @@ ms.assetid: d0511e80-904f-4ee1-b4d7-39b5c0bd8234 --- # Compiler Warning (level 4) C4268 -'identifier' : 'const' static/global data initialized with compiler generated default constructor fills the object with zeros +> 'identifier' : 'const' static/global data initialized with compiler generated default constructor fills the object with zeros A **`const`** global or static instance of a non-trivial class is initialized with a compiler-generated default constructor. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md b/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md index 75b41ea7dd..2aff8e8df9 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md @@ -5,7 +5,7 @@ ms.date: "11/6/2023" --- # Compiler Warning (levels 3 and 4) C4244 -'conversion' conversion from 'type1' to 'type2', possible loss of data +> 'conversion' conversion from 'type1' to 'type2', possible loss of data An integer type is converted to a smaller integer type. - This is a level-4 warning if *type1* is a signed or unsigned **`int`** and *type2* is a smaller, such as a signed or unsigned **`short`**. From d312b4aa643cb79716efb18d390462a82f95754a Mon Sep 17 00:00:00 2001 From: Rageking8 <106309953+Rageking8@users.noreply.github.com> Date: Wed, 27 Aug 2025 23:34:16 +0800 Subject: [PATCH 2/5] Add "Remarks" and "Example" headings for warning references in range [C4231, C4270] --- .../compiler-warnings/compiler-warning-level-1-c4237.md | 4 ++++ .../compiler-warnings/compiler-warning-level-1-c4258.md | 8 +++++++- .../compiler-warnings/compiler-warning-level-1-c4264.md | 2 ++ .../compiler-warnings/compiler-warning-level-1-c4269.md | 2 ++ .../compiler-warnings/compiler-warning-level-2-c4244.md | 2 ++ .../compiler-warnings/compiler-warning-level-2-c4250.md | 2 ++ .../compiler-warnings/compiler-warning-level-3-c4240.md | 2 ++ .../compiler-warnings/compiler-warning-level-3-c4243.md | 4 ++++ .../compiler-warnings/compiler-warning-level-3-c4265.md | 4 ++++ .../compiler-warnings/compiler-warning-level-3-c4267.md | 2 ++ .../compiler-warnings/compiler-warning-level-4-c4232.md | 4 ++++ .../compiler-warnings/compiler-warning-level-4-c4233.md | 2 ++ .../compiler-warnings/compiler-warning-level-4-c4234.md | 2 ++ .../compiler-warnings/compiler-warning-level-4-c4238.md | 2 ++ .../compiler-warnings/compiler-warning-level-4-c4239.md | 2 ++ .../compiler-warnings/compiler-warning-level-4-c4242.md | 4 ++++ .../compiler-warnings/compiler-warning-level-4-c4245.md | 4 ++++ .../compiler-warnings/compiler-warning-level-4-c4254.md | 4 ++++ .../compiler-warnings/compiler-warning-level-4-c4255.md | 4 ++++ .../compiler-warnings/compiler-warning-level-4-c4256.md | 4 ++++ .../compiler-warnings/compiler-warning-level-4-c4263.md | 4 ++++ .../compiler-warnings/compiler-warning-level-4-c4266.md | 4 ++++ .../compiler-warnings/compiler-warning-level-4-c4268.md | 2 ++ .../compiler-warning-levels-3-and-4-c4244.md | 4 ++++ 24 files changed, 77 insertions(+), 1 deletion(-) diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md index 3f67549fb3..1b96053d12 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md @@ -10,8 +10,12 @@ ms.assetid: f2e86c4b-80d8-460e-9429-83c5f3f5d7ca > 'keyword' keyword is not yet supported, but reserved for future use +## Remarks + A keyword in the C++ specification is not implemented in the Microsoft C++ compiler, but the keyword is not available as a user-defined symbol. +## Example + The following sample generates C4237: ```cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md index 3904ba4c66..e8617f23c7 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md @@ -10,7 +10,13 @@ ms.assetid: bbb75e6d-6693-4e62-8ed3-b006a0ec55e3 > 'variable' : definition from the for loop is ignored; the definition from the enclosing scope is used" -Under [/Ze](../../build/reference/za-ze-disable-language-extensions.md) and [/Zc:forScope](../../build/reference/zc-forscope-force-conformance-in-for-loop-scope.md), variables defined in a [for](../../cpp/for-statement-cpp.md) loop go out of scope after the **`for`** loop ends. This warning occurs if a variable with the same name as the loop variable, but defined in the enclosing loop, is used again in the scope containing the **`for`** loop. For example: +## Remarks + +Under [/Ze](../../build/reference/za-ze-disable-language-extensions.md) and [/Zc:forScope](../../build/reference/zc-forscope-force-conformance-in-for-loop-scope.md), variables defined in a [for](../../cpp/for-statement-cpp.md) loop go out of scope after the **`for`** loop ends. This warning occurs if a variable with the same name as the loop variable, but defined in the enclosing loop, is used again in the scope containing the **`for`** loop. + +## Example + +For example: ```cpp // C4258.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4264.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4264.md index 4fe4000068..04ab31ecfd 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4264.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4264.md @@ -9,6 +9,8 @@ helpviewer_keywords: ["C4264"] > 'virtual_function' : no override available for virtual member function from base 'class'; function is hidden +## Remarks + C4264 is always generated after [C4263](../../error-messages/compiler-warnings/compiler-warning-level-4-c4263.md). 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). diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md index 322895fb5f..d582ed2f12 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md @@ -9,6 +9,8 @@ helpviewer_keywords: ["C4269"] > 'identifier' : 'const' automatic data initialized with compiler generated default constructor produces unreliable results +## Remarks + A **`const`** automatic instance of a non-trivial class is initialized with a compiler-generated default constructor. ## Example diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md index c88d6b4d73..0c15ba251c 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md @@ -10,6 +10,8 @@ ms.assetid: 2c19d157-21d1-42c2-a6c0-3f30f2ce3813 > 'argument' : conversion from 'type1' to 'type2', possible loss of data +## Remarks + A floating point type was converted to an integer type. A possible loss of data may have occurred. If you get C4244, you should either change your program to use compatible types, or add some logic to your code, to ensure that the range of possible values will always be compatible with the types you are using. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md index 191ce3b1fe..0006e0a026 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md @@ -10,6 +10,8 @@ ms.assetid: d47f7249-6b5a-414b-b2d4-56e5d246a782 > 'class1' : inherits 'class2::member' via dominance +## Remarks + Two or more members have the same name. The one in `class2` is inherited because it is a base class for the other classes that contained this member. To suppress C4250, use the [warning](../../preprocessor/warning.md) pragma. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md index aa98f67f45..4c0d53e25f 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md @@ -10,6 +10,8 @@ ms.assetid: a2657cdb-18e1-493f-882b-4e10c0bca71d > nonstandard extension used : access to 'classname' now defined to be 'access specifier', previously it was defined to be 'access specifier' +## Remarks + Under ANSI compatibility ([/Za](../../build/reference/za-ze-disable-language-extensions.md)), you cannot change the access to a nested class. Under the default Microsoft extensions (/Ze), you can, with this warning. ## Example diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md index 1979eaf6c3..5fd56759f1 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md @@ -9,8 +9,12 @@ helpviewer_keywords: ["C4243"] > 'conversion type' conversion exists from 'type1' to 'type2', but is inaccessible +## Remarks + A pointer to a derived class is converted to a pointer to a base class, but the derived class inherits the base class with private or protected access. +## Example + The following sample generates C4243: ```cpp 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 index fa20cef811..62edba8961 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4265.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4265.md @@ -9,10 +9,14 @@ helpviewer_keywords: ["C4265"] > '*classname*': class has virtual functions, but its non-trivial destructor is not virtual; instances of this class may not be destructed correctly +## Remarks + 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. 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). +## Example + The following sample generates C4265: ```cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md index 537027a3bb..8c2ae4bc82 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md @@ -10,6 +10,8 @@ ms.assetid: 2fa2f13f-fa4f-47bb-ad8f-6cb19cfc91e6 > 'var' : conversion from 'size_t' to 'type', possible loss of data +## Remarks + The compiler detected a conversion from `size_t` to a smaller type. To fix this warning, use `size_t` instead of `type`. Alternatively, use an integral type that is at least as large as `size_t`. diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md index 47f53d3a3e..ccffc0d7e1 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md @@ -10,8 +10,12 @@ ms.assetid: f92028a5-4ddd-43c1-97f5-4f724e5e14af > nonstandard extension used : 'identifier' : address of dllimport 'dllimport' is not static, identity not guaranteed +## Remarks + Under Microsoft extensions (/Ze), you can give a nonstatic value as the address of a function declared with the **`dllimport`** modifier. Under ANSI compatibility ([/Za](../../build/reference/za-ze-disable-language-extensions.md)), this causes an error. +## Example + The following sample generates C4232: ```c 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 index 7987d2e583..525dbd22fe 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4233.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4233.md @@ -9,6 +9,8 @@ helpviewer_keywords: ["C4233"] > nonstandard extension used: '*keyword*' keyword only supported in C++, not C +## Remarks + 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 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-c4234.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md index b0fa52b455..331027fbff 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md @@ -10,6 +10,8 @@ ms.assetid: f7fecd5c-8248-4fde-8446-502aedc357ca > nonstandard extension used: 'keyword' keyword reserved for future use +## Remarks + The compiler does not yet implement the keyword you used. 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 C4234 into a level 4 warning issue, diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md index ac680a5ac5..cf660112a5 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md @@ -10,6 +10,8 @@ ms.assetid: 5d4051d3-7b0f-43ea-8c8d-d194bfdceb71 > nonstandard extension used : class rvalue used as lvalue +## Remarks + For compatibility with previous versions of Visual C++, Microsoft extensions (**/Ze**) allow you to use a class type as an rvalue in a context that implicitly or explicitly takes its address. In some cases, such as the example below, this can be dangerous. ## Example diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md index 3fd260094f..98a76da2a7 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md @@ -10,6 +10,8 @@ ms.assetid: a23dc16a-649e-4870-9a24-275de1584fcd > nonstandard extension used : 'token' : conversion from 'type' to 'type' +## Remarks + This type conversion is not allowed by the C++ standard, but it is permitted here as an extension. This warning is always followed by at least one line of explanation describing the language rule being violated. ## Examples 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 index f0d4ccb106..a4d2ad47bf 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4242.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4242.md @@ -9,12 +9,16 @@ helpviewer_keywords: ["C4242"] > '*identifier*': conversion from '*type1*' to '*type2*', possible loss of data +## Remarks + The types are different. Type conversion may result in loss of data. The compiler makes the type conversion. 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 more information on C4242, see [Common Compiler Errors](/windows/win32/WinProg64/common-compiler-errors). +## Example + The following sample generates C4242: ```cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md index 45dd045a04..cf52daba9f 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md @@ -10,8 +10,12 @@ ms.assetid: 85083d53-9cc2-4d12-b58c-6dad28f15cbe > '*conversion*' : conversion from '*type1*' to '*type2*', signed/unsigned mismatch +## Remarks + You tried to convert a **`signed const`** type that has a negative value to an **`unsigned`** type. +## Example + The following sample generates C4245: ```cpp 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 index dbcbdcc801..110f0188d7 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4254.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4254.md @@ -9,10 +9,14 @@ helpviewer_keywords: ["C4254"] > '*operator*': conversion from '*type1*':'*field_bits*' to '*type2*':'*field_bits*', possible loss of data +## Remarks + A larger bit field was assigned to a smaller bit field. There could be a loss of data. 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). +## Example + The following sample generates C4254: ```cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md index 4358f2e093..32c2bcfecd 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md @@ -9,10 +9,14 @@ helpviewer_keywords: ["C4255"] > 'function' : no function prototype given: converting '()' to '(void)' +## Remarks + The compiler didn't find an explicit list of arguments to a function. This warning is for the C compiler only. 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). +## Example + The following sample generates C4255: ```c diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md index fbde6eb7d7..8f8d9e2e8e 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md @@ -10,6 +10,8 @@ ms.assetid: a755a32e-895a-4837-a2b5-4ea06b736798 > 'function' : constructor for class with virtual bases has '...'; calls may not be compatible with older versions of Visual C++ +## Remarks + Possible incompatibility. Consider the following code example. If the definition of the constructor S2::S2( int i, ... ) was compiled by using a version of the Microsoft C++ compiler before version 7, but the following example is compiled by using the current version, the call to the constructor for S3 would not work correctly because of a special-case calling-convention change. If both were compiled by using Visual C++ 6.0, the call would not work quite right either, unless no parameters were passed for the ellipsis. @@ -20,6 +22,8 @@ To fix this warning, 1. Make sure that all components in their project are built with the current version (including any libraries that may define or reference this class), then disable the warning using the [warning](../../preprocessor/warning.md) pragma. +## Example + The following sample generates C4256: ```cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md index 7ea2676192..283fb1d137 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md @@ -9,10 +9,14 @@ helpviewer_keywords: ["C4263"] > 'function' : member function does not override any base class virtual member function +## Remarks + A class function definition has the same name as a virtual function in a base class but not the same number or type of arguments. This pattern effectively hides the virtual function in the base class. 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). +## Example + The following sample generates C4263: ```cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md index 88e8e554df..00e053dd81 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md @@ -9,10 +9,14 @@ helpviewer_keywords: ["C4266"] > 'function' : no override available for virtual member function from base 'type'; function is hidden +## Remarks + A derived class didn't override all overloads of a virtual function. 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). +## Example + The following sample generates C4266: ```cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md index 20efbfd9a7..b4148b5e6a 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md @@ -10,6 +10,8 @@ ms.assetid: d0511e80-904f-4ee1-b4d7-39b5c0bd8234 > 'identifier' : 'const' static/global data initialized with compiler generated default constructor fills the object with zeros +## Remarks + A **`const`** global or static instance of a non-trivial class is initialized with a compiler-generated default constructor. ## Example diff --git a/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md b/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md index 2aff8e8df9..3ead28e428 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md @@ -7,6 +7,8 @@ ms.date: "11/6/2023" > 'conversion' conversion from 'type1' to 'type2', possible loss of data +## Remarks + An integer type is converted to a smaller integer type. - This is a level-4 warning if *type1* is a signed or unsigned **`int`** and *type2* is a smaller, such as a signed or unsigned **`short`**. - It's a level 3 warning if a value of type [`__int64`](../../cpp/int8-int16-int32-int64.md) or **`unsigned __int64`** is assigned to a signed or unsigned **`int`**. A possible loss of data may have occurred due to a narrowing conversion, which might lead to unexpected results. @@ -15,6 +17,8 @@ To fix this warning, either change your program to use compatible types, or add C4244 can also appear when the warning level is 2. For more information, see [Compiler Warning (level 2) C4244](../../error-messages/compiler-warnings/compiler-warning-level-2-c4244.md). +## Examples + The following sample generates C4244: ```cpp From 933dfe85b2015254e4e8619f4188edf9b1bded29 Mon Sep 17 00:00:00 2001 From: Rageking8 <106309953+Rageking8@users.noreply.github.com> Date: Wed, 27 Aug 2025 23:35:51 +0800 Subject: [PATCH 3/5] Replace term "sample" with "example" for warning references in range [C4231, C4270] --- .../compiler-warnings/compiler-warning-level-1-c4237.md | 2 +- .../compiler-warnings/compiler-warning-level-2-c4244.md | 2 +- .../compiler-warnings/compiler-warning-level-2-c4250.md | 4 ++-- .../compiler-warnings/compiler-warning-level-3-c4243.md | 2 +- .../compiler-warnings/compiler-warning-level-3-c4265.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4232.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4239.md | 4 ++-- .../compiler-warnings/compiler-warning-level-4-c4242.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4245.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4254.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4255.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4256.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4263.md | 2 +- .../compiler-warnings/compiler-warning-level-4-c4266.md | 2 +- .../compiler-warning-levels-3-and-4-c4244.md | 4 ++-- 15 files changed, 18 insertions(+), 18 deletions(-) diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md index 1b96053d12..c9cb6149d8 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md @@ -16,7 +16,7 @@ A keyword in the C++ specification is not implemented in the Microsoft C++ compi ## Example -The following sample generates C4237: +The following example generates C4237: ```cpp // C4237.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md index 0c15ba251c..16b7ef79e6 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md @@ -20,7 +20,7 @@ C4244 can also fire at level 3, and 4; see [Compiler Warning (levels 3 and 4) C4 ## Example -The following sample generates C4244: +The following example generates C4244: ```cpp // C4244_level2.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md index 0006e0a026..d2752a821a 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md @@ -42,7 +42,7 @@ int main() { } ``` -The following sample generates C4250. +The following example generates C4250. ```cpp // C4250_b.cpp @@ -73,7 +73,7 @@ int main() { } ``` -This sample shows a more complex situation. The following sample generates C4250. +This example shows a more complex situation. The following example generates C4250. ```cpp // C4250_c.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md index 5fd56759f1..6b8dd2c801 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4243.md @@ -15,7 +15,7 @@ A pointer to a derived class is converted to a pointer to a base class, but the ## Example -The following sample generates C4243: +The following example generates C4243: ```cpp // C4243.cpp 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 index 62edba8961..e8f511b5bf 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4265.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4265.md @@ -17,7 +17,7 @@ This warning is off by default. For more information, see [Compiler Warnings Tha ## Example -The following sample generates C4265: +The following example generates C4265: ```cpp // C4265.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md index ccffc0d7e1..e10bb22266 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md @@ -16,7 +16,7 @@ Under Microsoft extensions (/Ze), you can give a nonstatic value as the address ## Example -The following sample generates C4232: +The following example generates C4232: ```c // C4232.c diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md index 98a76da2a7..6797b2db79 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md @@ -16,7 +16,7 @@ This type conversion is not allowed by the C++ standard, but it is permitted her ## Examples -The following sample generates C4239. +The following example generates C4239. ```cpp // C4239.cpp @@ -34,7 +34,7 @@ void func(void) { Conversion from integral type to enum type is not strictly allowed. -The following sample generates C4239. +The following example generates C4239. ```cpp // C4239b.cpp 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 index a4d2ad47bf..defc25de93 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4242.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4242.md @@ -19,7 +19,7 @@ For more information on C4242, see [Common Compiler Errors](/windows/win32/WinPr ## Example -The following sample generates C4242: +The following example generates C4242: ```cpp // C4242.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md index cf52daba9f..ed117fd123 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md @@ -16,7 +16,7 @@ You tried to convert a **`signed const`** type that has a negative value to an * ## Example -The following sample generates C4245: +The following example generates C4245: ```cpp // C4245.cpp 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 index 110f0188d7..03aa6d9f42 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4254.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4254.md @@ -17,7 +17,7 @@ This warning is off by default. For more information, see [Compiler Warnings Tha ## Example -The following sample generates C4254: +The following example generates C4254: ```cpp // C4254.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md index 32c2bcfecd..3cf27c00e0 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md @@ -17,7 +17,7 @@ This warning is off by default. For more information, see [Compiler Warnings Tha ## Example -The following sample generates C4255: +The following example generates C4255: ```c // C4255.c diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md index 8f8d9e2e8e..c3c017fabe 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md @@ -24,7 +24,7 @@ To fix this warning, ## Example -The following sample generates C4256: +The following example generates C4256: ```cpp // C4256.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md index 283fb1d137..450639f969 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md @@ -17,7 +17,7 @@ This warning is off by default. For more information, see [Compiler Warnings Tha ## Example -The following sample generates C4263: +The following example generates C4263: ```cpp // C4263.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md index 00e053dd81..50751d8f38 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md @@ -17,7 +17,7 @@ This warning is off by default. For more information, see [Compiler Warnings Tha ## Example -The following sample generates C4266: +The following example generates C4266: ```cpp // C4266.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md b/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md index 3ead28e428..378fbc9927 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md @@ -19,7 +19,7 @@ C4244 can also appear when the warning level is 2. For more information, see [Co ## Examples -The following sample generates C4244: +The following example generates C4244: ```cpp // C4244_level4.cpp @@ -56,7 +56,7 @@ int main() { Warning C4244 can occur when building code for 64-bit targets that doesn't generate the warning when building for 32-bit targets. For example, pointer arithmetic results in a 32-bit quantity on 32-bit platforms, but a 64-bit quantity on 64-bit platforms. -The following sample generates C4244 when compiled for 64-bit targets: +The following example generates C4244 when compiled for 64-bit targets: ```cpp // C4244_level3_b.cpp From 21a2745ce5cb5192c786bfaee852e59664891b3a Mon Sep 17 00:00:00 2001 From: Rageking8 <106309953+Rageking8@users.noreply.github.com> Date: Wed, 27 Aug 2025 23:39:52 +0800 Subject: [PATCH 4/5] Update metadata for warning references in range [C4231, C4270] --- .../compiler-warnings/compiler-warning-level-1-c4237.md | 5 ++--- .../compiler-warnings/compiler-warning-level-1-c4258.md | 5 ++--- .../compiler-warnings/compiler-warning-level-1-c4264.md | 4 ++-- .../compiler-warnings/compiler-warning-level-2-c4244.md | 5 ++--- .../compiler-warnings/compiler-warning-level-2-c4250.md | 5 ++--- .../compiler-warnings/compiler-warning-level-3-c4240.md | 5 ++--- .../compiler-warnings/compiler-warning-level-3-c4265.md | 4 ++-- .../compiler-warnings/compiler-warning-level-3-c4267.md | 5 ++--- .../compiler-warnings/compiler-warning-level-4-c4232.md | 5 ++--- .../compiler-warnings/compiler-warning-level-4-c4233.md | 4 ++-- .../compiler-warnings/compiler-warning-level-4-c4234.md | 5 ++--- .../compiler-warnings/compiler-warning-level-4-c4238.md | 5 ++--- .../compiler-warnings/compiler-warning-level-4-c4239.md | 5 ++--- .../compiler-warnings/compiler-warning-level-4-c4242.md | 4 ++-- .../compiler-warnings/compiler-warning-level-4-c4245.md | 5 ++--- .../compiler-warnings/compiler-warning-level-4-c4255.md | 4 ++-- .../compiler-warnings/compiler-warning-level-4-c4256.md | 5 ++--- .../compiler-warnings/compiler-warning-level-4-c4263.md | 4 ++-- .../compiler-warnings/compiler-warning-level-4-c4266.md | 4 ++-- .../compiler-warnings/compiler-warning-level-4-c4268.md | 5 ++--- .../compiler-warning-levels-3-and-4-c4244.md | 4 ++-- 21 files changed, 42 insertions(+), 55 deletions(-) diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md index c9cb6149d8..122af02412 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4237.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 1) C4237" title: "Compiler Warning (level 1) C4237" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 1) C4237" +ms.date: 11/04/2016 f1_keywords: ["C4237"] helpviewer_keywords: ["C4237"] -ms.assetid: f2e86c4b-80d8-460e-9429-83c5f3f5d7ca --- # Compiler Warning (level 1) C4237 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md index e8617f23c7..a29bd856a5 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4258.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 1) C4258" title: "Compiler Warning (level 1) C4258" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 1) C4258" +ms.date: 11/04/2016 f1_keywords: ["C4258"] helpviewer_keywords: ["C4258"] -ms.assetid: bbb75e6d-6693-4e62-8ed3-b006a0ec55e3 --- # Compiler Warning (level 1) C4258 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4264.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4264.md index 04ab31ecfd..a781621f80 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4264.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4264.md @@ -1,7 +1,7 @@ --- -description: "Learn more about: Compiler Warning (level 4, off) C4264" title: "Compiler Warning (level 4, off) C4264" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4, off) C4264" +ms.date: 11/04/2016 f1_keywords: ["C4264"] helpviewer_keywords: ["C4264"] --- diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md index 16b7ef79e6..e2c76f5572 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4244.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 2) C4244" title: "Compiler Warning (level 2) C4244" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 2) C4244" +ms.date: 11/04/2016 f1_keywords: ["C4244"] helpviewer_keywords: ["C4244"] -ms.assetid: 2c19d157-21d1-42c2-a6c0-3f30f2ce3813 --- # Compiler Warning (level 2) C4244 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md index d2752a821a..307af8f0eb 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 2) C4250" title: "Compiler Warning (level 2) C4250" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 2) C4250" +ms.date: 11/04/2016 f1_keywords: ["C4250"] helpviewer_keywords: ["C4250"] -ms.assetid: d47f7249-6b5a-414b-b2d4-56e5d246a782 --- # Compiler Warning (level 2) C4250 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md index 4c0d53e25f..d7576d2dca 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 3) C4240" title: "Compiler Warning (level 3) C4240" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 3) C4240" +ms.date: 11/04/2016 f1_keywords: ["C4240"] helpviewer_keywords: ["C4240"] -ms.assetid: a2657cdb-18e1-493f-882b-4e10c0bca71d --- # Compiler Warning (level 3) C4240 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 index e8f511b5bf..7fecde7c7e 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4265.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4265.md @@ -1,7 +1,7 @@ --- -description: "Learn more about: Compiler Warning (level 3, off) C4265" title: "Compiler Warning (level 3, off) C4265" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 3, off) C4265" +ms.date: 11/04/2016 f1_keywords: ["C4265"] helpviewer_keywords: ["C4265"] --- diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md index 8c2ae4bc82..3b6989d674 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4267.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 3) C4267" title: "Compiler Warning (level 3) C4267" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 3) C4267" +ms.date: 11/04/2016 f1_keywords: ["C4267"] helpviewer_keywords: ["C4267"] -ms.assetid: 2fa2f13f-fa4f-47bb-ad8f-6cb19cfc91e6 --- # Compiler Warning (level 3) C4267 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md index e10bb22266..392aa103b9 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4232.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 4) C4232" title: "Compiler Warning (level 4) C4232" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4) C4232" +ms.date: 11/04/2016 f1_keywords: ["C4232"] helpviewer_keywords: ["C4232"] -ms.assetid: f92028a5-4ddd-43c1-97f5-4f724e5e14af --- # Compiler Warning (level 4) C4232 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 index 525dbd22fe..0ada63cf90 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4233.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4233.md @@ -1,7 +1,7 @@ --- -description: "Learn more about: Compiler Warning (level 1, Error) C4233" title: "Compiler Warning (level 1, Error) C4233" -ms.date: "10/25/2017" +description: "Learn more about: Compiler Warning (level 1, Error) C4233" +ms.date: 10/25/2017 f1_keywords: ["C4233"] helpviewer_keywords: ["C4233"] --- diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md index 331027fbff..65c487e016 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4234.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 4) C4234" title: "Compiler Warning (level 4) C4234" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4) C4234" +ms.date: 11/04/2016 f1_keywords: ["C4234"] helpviewer_keywords: ["C4234"] -ms.assetid: f7fecd5c-8248-4fde-8446-502aedc357ca --- # Compiler Warning (level 4) C4234 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md index cf660112a5..cef575afd7 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 4) C4238" title: "Compiler Warning (level 4) C4238" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4) C4238" +ms.date: 11/04/2016 f1_keywords: ["C4238"] helpviewer_keywords: ["C4238"] -ms.assetid: 5d4051d3-7b0f-43ea-8c8d-d194bfdceb71 --- # Compiler Warning (level 4) C4238 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md index 6797b2db79..ead032c4b0 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4239.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 4) C4239" title: "Compiler Warning (level 4) C4239" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4) C4239" +ms.date: 11/04/2016 f1_keywords: ["C4239"] helpviewer_keywords: ["C4239"] -ms.assetid: a23dc16a-649e-4870-9a24-275de1584fcd --- # Compiler Warning (level 4) C4239 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 index defc25de93..e122d51b7c 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4242.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4242.md @@ -1,7 +1,7 @@ --- -description: "Learn more about: Compiler Warning (level 3, off) C4242" title: "Compiler Warning (level 3, off) C4242" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 3, off) C4242" +ms.date: 11/04/2016 f1_keywords: ["C4242"] helpviewer_keywords: ["C4242"] --- diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md index ed117fd123..051b324035 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4245.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 4) C4245" title: "Compiler Warning (level 4) C4245" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4) C4245" +ms.date: 11/04/2016 f1_keywords: ["C4245"] helpviewer_keywords: ["C4245"] -ms.assetid: 85083d53-9cc2-4d12-b58c-6dad28f15cbe --- # Compiler Warning (level 4) C4245 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md index 3cf27c00e0..0627f04d95 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4255.md @@ -1,7 +1,7 @@ --- -description: "Learn more about: Compiler Warning (level 4, off) C4255" title: "Compiler Warning (level 4, off) C4255" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4, off) C4255" +ms.date: 11/04/2016 f1_keywords: ["C4255"] helpviewer_keywords: ["C4255"] --- diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md index c3c017fabe..c7a310e4c0 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4256.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 4) C4256" title: "Compiler Warning (level 4) C4256" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4) C4256" +ms.date: 11/04/2016 f1_keywords: ["C4256"] helpviewer_keywords: ["C4256"] -ms.assetid: a755a32e-895a-4837-a2b5-4ea06b736798 --- # Compiler Warning (level 4) C4256 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md index 450639f969..a12a0c9846 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4263.md @@ -1,7 +1,7 @@ --- -description: "Learn more about: Compiler Warning (level 4, off) C4263" title: "Compiler Warning (level 4, off) C4263" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4, off) C4263" +ms.date: 11/04/2016 f1_keywords: ["C4263"] helpviewer_keywords: ["C4263"] --- diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md index 50751d8f38..9d1dcb0c85 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4266.md @@ -1,7 +1,7 @@ --- -description: "Learn more about: Compiler Warning (level 4, off) C4266" title: "Compiler Warning (level 4, off) C4266" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4, off) C4266" +ms.date: 11/04/2016 f1_keywords: ["C4266"] helpviewer_keywords: ["C4266"] --- diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md index b4148b5e6a..f463e36ffa 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md @@ -1,10 +1,9 @@ --- -description: "Learn more about: Compiler Warning (level 4) C4268" title: "Compiler Warning (level 4) C4268" -ms.date: "11/04/2016" +description: "Learn more about: Compiler Warning (level 4) C4268" +ms.date: 11/04/2016 f1_keywords: ["C4268"] helpviewer_keywords: ["C4268"] -ms.assetid: d0511e80-904f-4ee1-b4d7-39b5c0bd8234 --- # Compiler Warning (level 4) C4268 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md b/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md index 378fbc9927..68800ee8c0 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-levels-3-and-4-c4244.md @@ -1,7 +1,7 @@ --- -description: "Learn more about: Compiler Warning (levels 3 and 4) C4244" title: "Compiler Warning (levels 3 and 4) C4244" -ms.date: "11/6/2023" +description: "Learn more about: Compiler Warning (levels 3 and 4) C4244" +ms.date: 11/6/2023 --- # Compiler Warning (levels 3 and 4) C4244 From f4f370d80c0335ae442a27867c5b1338b6d2c992 Mon Sep 17 00:00:00 2001 From: Rageking8 <106309953+Rageking8@users.noreply.github.com> Date: Wed, 27 Aug 2025 23:43:33 +0800 Subject: [PATCH 5/5] Add leading example sentence for warning references in range [C4231, C4270] --- .../compiler-warnings/compiler-warning-level-1-c4251.md | 2 ++ .../compiler-warnings/compiler-warning-level-1-c4269.md | 2 ++ .../compiler-warnings/compiler-warning-level-2-c4250.md | 2 ++ .../compiler-warnings/compiler-warning-level-3-c4240.md | 2 ++ .../compiler-warnings/compiler-warning-level-4-c4238.md | 2 ++ .../compiler-warnings/compiler-warning-level-4-c4268.md | 2 ++ 6 files changed, 12 insertions(+) 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 index 1056b7868c..b0b11764a1 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4251.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4251.md @@ -32,6 +32,8 @@ Think carefully about adding `__declspec(dllexport)` or `__declspec(dllimport)` ## Example +The following example generates C4251: + ```cpp // C4251.cpp // Compile with /std:c++20 /EHsc /W2 /c C4251.cpp diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md index d582ed2f12..d5b610b759 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-1-c4269.md @@ -15,6 +15,8 @@ A **`const`** automatic instance of a non-trivial class is initialized with a co ## Example +The following example generates C4269: + ```cpp // C4269.cpp // compile with: /c /LD /W1 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md index 307af8f0eb..b42f61f058 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-2-c4250.md @@ -19,6 +19,8 @@ Because a virtual base class is shared among multiple derived classes, a name in ## Examples +The following example generates C4250: + ```cpp // C4250.cpp // compile with: /c /W2 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md index d7576d2dca..529f6f70f3 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-3-c4240.md @@ -15,6 +15,8 @@ Under ANSI compatibility ([/Za](../../build/reference/za-ze-disable-language-ext ## Example +The following example generates C4240: + ```cpp // C4240.cpp // compile with: /W3 diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md index cef575afd7..686daa1f66 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4238.md @@ -15,6 +15,8 @@ For compatibility with previous versions of Visual C++, Microsoft extensions (** ## Example +The following example generates C4238: + ```cpp // C4238.cpp // compile with: /W4 /c diff --git a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md index f463e36ffa..1ec1be3976 100644 --- a/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md +++ b/docs/error-messages/compiler-warnings/compiler-warning-level-4-c4268.md @@ -15,6 +15,8 @@ A **`const`** global or static instance of a non-trivial class is initialized wi ## Example +The following example generates C4268: + ```cpp // C4268.cpp // compile with: /c /LD /W4