Bug 20086 - Incorrect report of error CS0165 of assigned variable.
Summary: Incorrect report of error CS0165 of assigned variable.
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2014-05-28 05:05 UTC by Lewis Cheng
Modified: 2014-05-28 10:25 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description Lewis Cheng 2014-05-28 05:05:15 UTC
Test case:

public class A {                                                                                                                                    
    public static bool TryAssign(out int x) {
       x = 0;
       return true;
    public static void Main() {
       int x, y;
       if ((!TryAssign(out x) || x == 0) & (!TryAssign(out y) || y == 0)) {

Will report error CS0165: Use of unassigned local variable 'y'.

I guess the problem is with Binary.FlowAnalysis, where 'y == 0' gets the wrong DefiniteAssignment before line 2636 'right.FlowAnalysis(fc)'?

Comment 1 Marek Safar 2014-05-28 10:25:16 UTC
Fixe in master