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Bug 136676

Summary:	[compiler][null][correlation] warns "may be null" within block that would be unreachable if arg was null
Product:	[Eclipse Project] JDT	Reporter:	Grant Gayed <grant_gayed>
Component:	Core	Assignee:	JDT-Core-Inbox <jdt-core-inbox>
Status:	CLOSED DUPLICATE	QA Contact:
Severity:	enhancement
Priority:	P5	CC:	feles, nilskp+eclipse, stephan.herrmann, vlsergey
Version:	3.2	Keywords:	helpwanted
Target Milestone:	4.7 M1
Hardware:	PC
OS:	All
Whiteboard:

Description Grant Gayed

2006-04-13 12:20:26 EDT

snippet:

public static void main(String[] args) {
    String abc = System.currentTimeMillis() % 2 == 0 ? "abc" : null;
    boolean doit = abc != null;
    if (doit) {
        System.out.println(abc.length());  // <-- cannnot get here if abc==null
    }
}

Comment 1 Maxime Daniel

2006-04-13 12:27:10 EDT

This is a slightly simpler case than bug 134933. This calls for variables correlation, which is not in 3.2 scope.

Comment 2 Maxime Daniel

2006-07-10 11:10:58 EDT

*** Bug 150123 has been marked as a duplicate of this bug. ***

Comment 3 Maxime Daniel

2006-07-26 03:01:00 EDT

*** Bug 151725 has been marked as a duplicate of this bug. ***

Comment 4 Maxime Daniel

2006-08-24 13:07:58 EDT

*** Bug 155043 has been marked as a duplicate of this bug. ***

Comment 5 Maxime Daniel

2007-06-19 08:07:53 EDT

Reopening as P5 (since RESOLVED LATER is deprecated).

Comment 6 Stephan Herrmann

2016-06-28 17:17:34 EDT

Bulk closing all compiler bugs tagged [null][correlation], because we have no plans to add such a feature: it would be a tremendous implementation effort, beyond our current man power, and may be impossible to achieve within the desired performance bounds.

If s.o. has a viable strategy or even implementation for such a feature, I'm all ears.

Comment 7 Jay Arthanareeswaran

2016-08-03 07:58:16 EDT

Verified for 4.7 M1.

Comment 8 Stephan Herrmann

2018-08-30 10:32:12 EDT

I created a new umbrella RFE outlining what would be needed to address this issue.

*** This bug has been marked as a duplicate of bug 538421 ***