# Improvements to C# analysis

## General improvements

* Control flow graph improvements:
* The control flow graph construction now takes simple Boolean conditions on local scope variables into account. For example, in `if (b) x = 0; if (b) x = 1;`, the control flow graph will reflect that taking the `true` (resp. `false`) branch in the first condition implies taking the same branch in the second condition. In effect, the first assignment to `x` will now be identified as being dead.
  * Code that is only reachable from a constant failing assertion, such as `Debug.Assert(false)`, is considered to be unreachable.

## New queries

| **Query**                   | **Tags**  | **Purpose**                                                        |
|-----------------------------|-----------|--------------------------------------------------------------------|
| *@name of query (Query ID)* | *Tags*    |*Aim of the new query and whether it is enabled by default or not*  |

## Changes to existing queries

| Inconsistent lock sequence (`cs/inconsistent-lock-sequence`) | More results | This query now finds inconsistent lock sequences globally across calls. |
| Local scope variable shadows member (`cs/local-shadows-member`) | Fewer results | Results have been removed where a constructor parameter shadows a member, because the parameter is probably used to initialize the member. |
| Cross-site scripting (`cs/web/xss`) | More results | This query now finds cross-site scripting vulnerabilities in ASP.NET Core applications. |
| *@name of query (Query ID)*| *Impact on results*    | *How/why the query has changed*                                  |


## Changes to QL libraries