Updated C6334

Updated to new format, clarified wording, matched spacing to my other PRs

Author: MugBergerFries

docs/code-quality/c6334.md

@@ -1,54 +1,45 @@
 ---
 description: "Learn more about: C6334"
 title: C6334
-ms.date: 11/04/2016
+ms.date: 08/25/2022
 ms.topic: reference
-f1_keywords: ["C6334"]
+f1_keywords: ["C6334", "SIZEOFEXPR", "__WARNING_SIZEOFEXPR"]
 helpviewer_keywords: ["C6334"]
 ms.assetid: 83c8abfb-b11e-4573-8c6f-95b205d32137
 ---
-# C6334
+# Warning C6334
 
-> warning C6334: sizeof operator applied to an expression with an operator may yield unexpected results
+> sizeof operator applied to an expression with an operator may yield unexpected results
 
-This warning indicates a misuse of the **`sizeof`** operator. The **`sizeof`** operator, when applied to an expression, yields the size of the type of the resulting expression.
+## Remarks
 
-For example, in the following code:
+The `sizeof` operator, when applied to an expression, yields the size of the type of the resulting expression.
 
-```cpp
-char     a[10];
-size_t   x;
-
-x = sizeof (a - 1);
-```
-
- `x` will be assigned the value 4, not 9, because the resulting expression is no longer a pointer to the array `a`, but simply a pointer.
+Code analysis name: SIZEOFEXPR
 
 ## Example
 
-The following code generates this warning:
+The following code generates this warning. Since `a - 4` is an expression, `sizeof` will return the size of the resulting pointer, not the size of the structure found at that pointer:
 
 ```cpp
 void f( )
 {
-  size_t x;
-  char a[10];
-
-  x= sizeof (a - 4);
-  // code...
+    size_t x;
+    char a[100];
+    x = sizeof(a - 4);
+    assert(x == 96);  //assert fails since x == sizeof(char*)
 }
 ```
 
-To correct this warning, use the following code:
+To correct this warning, ensure you are working with the return value of `sizeof`, not the argument to it:
 
 ```cpp
 void f( )
 {
-  size_t x;
-  char a[10];
-
-  x= sizeof (a) - 4;
-  // code...
+    size_t x;
+    char a[100];
+    x = sizeof(a) - 4;
+    assert(x == 96);  //assert succeeds
 }
 ```