Merge pull request #5769 from TylerMSFT/checkstack

update per behavior verified Feb 2025

Author: denrea

docs/preprocessor/check-stack.md

@@ -1,9 +1,9 @@
 ---
 description: "Learn more about the check_stack pragma directive in Microsoft C/C++"
 title: "check_stack pragma"
-ms.date: 01/22/2021
+ms.date: 2/7/2025
 f1_keywords: ["vc-pragma.check_stack", "check_stack_CPP"]
-helpviewer_keywords: ["check_stack pragma", "pragma, check_stack", "pragma, check_stack usage table"]
+helpviewer_keywords: ["check_stack pragma", "pragma, check_stack"]
 no-loc: ["pragma"]
 ---
 # `check_stack` pragma
@@ -12,24 +12,24 @@ Instructs the compiler to turn off stack probes if **`off`** (or **`-`**) is spe
 
 ## Syntax
 
-> **`#pragma check_stack(`** [{ **`on`** | **`off`** }] **`)`**\
+> **`#pragma check_stack(`** { **`on`** | **`off`** } **`)`**\
 > **`#pragma check_stack`** { **`+`** | **`-`** }
 
 ## Remarks
 
-This pragma takes effect at the first function defined after the pragma is seen. Stack probes are neither a part of macros nor of functions that are generated inline.
+This pragma only applies to 32-bit platforms (x86, ARM32). It has no effect on 64-bit platforms.
 
-If you don't give an argument for the **`check_stack`** pragma, stack checking reverts to the behavior specified on the command line. For more information, see [Compiler options](../build/reference/compiler-options.md). The interaction of the `#pragma check_stack` and the [`/Gs`](../build/reference/gs-control-stack-checking-calls.md) option is summarized in the following table.
+This pragma takes effect at the first function defined after the pragma is seen. Stack probes are not inserted for macros or functions that are generated inline.
 
-### Using the check_stack Pragma
+`#pragma check_stack(off)` / `#pragma Check_stack-` is ignored if the size of the function locals is larger than 4096 or the value specified by `/Gs`.
 
-| Syntax | Compiled with<br /><br /> `/Gs` option? | Action |
-|--|--|--|
-| `#pragma check_stack( )` or<br /><br /> `#pragma check_stack` | Yes | Turns off stack checking for functions that follow |
-| `#pragma check_stack( )` or<br /><br /> `#pragma check_stack` | No | Turns on stack checking for functions that follow |
-| `#pragma check_stack(on)`<br /><br /> or `#pragma check_stack +` | Yes or No | Turns on stack checking for functions that follow |
-| `#pragma check_stack(off)`<br /><br /> or `#pragma check_stack -` | Yes or No | Turns off stack checking for functions that follow |
+The default behavior of the compiler is to insert stack probes at the beginning of each function if the size of the locals exceeds 4096 or the value specified by `/Gs`.
+
+Use [/Gs (Control stack checking calls)](../build/reference/gs-control-stack-checking-calls.md) to change the threshold of the locals that trigger stack probes. Use with caution.
+
+Using `#pragma check_stack()` without arguments is deprecated.
 
 ## See also
 
+[Compiler options](../build/reference/compiler-options.md)\
 [Pragma directives and the `__pragma` and `_Pragma` keywords](./pragma-directives-and-the-pragma-keyword.md)