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TylerMSFT · TylerMSFT · commit 70f19b48da73 · 2025-01-15T10:15:17.000-08:00
diff --git a/docs/cpp/declspec.md b/docs/cpp/declspec.md
@@ -1,15 +1,15 @@
 ---
 description: "Learn more about: `__declspec`"
 title: "__declspec"
-ms.date: 03/01/2022
+ms.date: 1/14/2025
 f1_keywords: ["__declspec_cpp", "__declspec", "_declspec"]
 helpviewer_keywords: ["__declspec keyword [C++]"]
 ---
 # `__declspec`
 
 **Microsoft Specific**
 
-The extended attribute syntax for specifying storage-class information uses the **`__declspec`** keyword, which specifies that an instance of a given type is to be stored with a Microsoft-specific storage-class attribute listed below. Examples of other storage-class modifiers include the **`static`** and **`extern`** keywords. However, these keywords are part of the ANSI specification of the C and C++ languages, and as such aren't covered by extended attribute syntax. The extended attribute syntax simplifies and standardizes Microsoft-specific extensions to the C and C++ languages.
+The extended attribute syntax for specifying storage-class information uses the `__declspec` keyword, which specifies that an instance of a given type is to be stored with a Microsoft-specific storage-class attribute listed below. Examples of other storage-class modifiers include the `static` and `extern` keywords. However, these keywords are part of the ANSI specification of the C and C++ languages, and as such aren't covered by extended attribute syntax. The extended attribute syntax simplifies and standardizes Microsoft-specific extensions to the C and C++ languages.
 
 ## Grammar
 
@@ -30,6 +30,7 @@ The extended attribute syntax for specifying storage-class information uses the
 &emsp;**`dllimport`**\
 &emsp;**`dllexport`**\
 &emsp;**`empty_bases`**\
+&emsp;**`hybrid_patchable`**\
 &emsp;**`jitintrinsic`**\
 &emsp;**`naked`**\
 &emsp;**`noalias`**\
diff --git a/docs/cpp/hybrid-patchable.md b/docs/cpp/hybrid-patchable.md
@@ -0,0 +1,56 @@
+---
+description: "Learn more about: hybrid_patchable (C++)"
+title: "hybrid_patchable (C++)"
+ms.date: 1/15/2025
+f1_keywords: ["hybrid_patchable"]
+helpviewer_keywords: ["__declspec keyword [C++], hybrid_patchable", "hybrid_patchable __declspec keyword"]
+---
+# `hybrid_patchable` (C++)
+
+**Microsoft Specific**
+
+Use **`__declspec(hybrid_patchable)`** extended attribute which can be used in the declaration of functions.
+
+## Syntax
+
+> `__declspec(hybrid_patchable)`
+
+## Remarks
+
+We recommend that all new code use the [`noexcept`](noexcept-cpp.md) operator rather than `__declspec(nothrow)`.
+
+This attribute tells the compiler that the declared function and the functions it calls never throw an exception. However, it does not enforce the directive. In other words, it never causes [`std::terminate`](../standard-library/exception-functions.md#terminate) to be invoked, unlike **`noexcept`**, or in **`std:c++17`** mode (Visual Studio 2017 version 15.5 and later), `throw()`.
+
+With the synchronous exception handling model, now the default, the compiler can eliminate the mechanics of tracking the lifetime of certain unwindable objects in such a function, and significantly reduce the code size. Given the following preprocessor directive, the three function declarations below are equivalent in **`/std:c++14`** mode:
+
+```cpp
+__declspec(hybrid_patchable) int Example() {
+    return 1;
+}
+```
+
+Generates the following fast-forward sequence:
+
+```
+EXP+#Example:
+  00000001400CE000: 48 8B C4           mov         rax,rsp
+  00000001400CE003: 48 89 58 20        mov         qword ptr [rax+20h],rbx
+  00000001400CE007: 55                 push        rbp
+  00000001400CE008: 5D                 pop         rbp
+  00000001400CE009: E9 BA 7A F3 FF     jmp         #Example
+  00000001400CE00E: CC                 int         3
+  00000001400CE00F: CC                 int         3 
+```
+
+
+In **`/std:c++17`** mode, `throw()` is not equivalent to the others that use `__declspec(nothrow)` because it causes `std::terminate` to be invoked if an exception is thrown from the function.
+
+The `void __stdcall f3() throw();` declaration uses the syntax defined by the C++ standard. In C++17 the `throw()` keyword was deprecated.
+
+**END Microsoft Specific**
+
+## See also
+
+[`__declspec`](../cpp/declspec.md)\
+[`noexcept`](noexcept-cpp.md)\
+[Keywords](../cpp/keywords-cpp.md)
diff --git a/docs/cpp/toc.yml b/docs/cpp/toc.yml
@@ -696,6 +696,8 @@ items:
                   href: ../cpp/using-dllimport-and-dllexport-in-cpp-classes.md
             - name: empty_bases
               href: ../cpp/empty-bases.md
+            - name: hybrid_patchable
+              href: ../cpp/hybrid-patchable.md
             - name: jitintrinsic
               href: ../cpp/jitintrinsic.md
             - name: naked
