javac数据流分析的奇怪的假阳性

问题描述

我有以下形式的代码：

  
 
删除中的 （） 
 
 
用替换循环，例如  for（int i = 0; i  
 
  
 $ b b 
它会编译。
解决方案
由于问题在Java 7中已修复， Java 6编译器。
 
I have code of the following form:
class Test {
  private final A t;

  public Test() {

    for ( ... : ... ) {
      final A u = null;
    }

    t = new A();
  }

  private class A {}
}
Compiler says:
variable t might already have been assigned
Interestingly, if I perform any of the following changes to the loop it works out! 
Change the loop's content to A u = null
Remove the loop (but keep final A u = null;)
Replace the foreach-style loop with a classic counting loop
What is going on here?
Note: I could not get the minimal example to cause the error so there is probably something wrong with the "environment" (about 1400 loc). I can not see what could disturb the initialisation of t, though, as t is written to nowhere else.
Fun fact: IntelliJ IDEA says "Variable 'u' can have 'final' modifier..." if I remove it.
I use javac 1.6.0_26.
Update: There you go, this example so so minimal:
import java.util.List;

class A {
  private final boolean a;

  public A() {
    for ( final Object o : new Object[] {} ) {
      final Object sh = null;
    }

    a = true;
  }

  class B {
    private final Object b1;
    private final Object b2;

    B() {
      b1 = null;
      b2 = null;
    }
  }
}
Fails to compile on javac 1.6.0_26 but compiles on javac 1.7.0_02. So I guess I hit some wicked corner case of ... something?
Note that you can do any of
Remove any one member
Remove final inside the loop in A()
Replace the loop with a normal for loop, e.g. for ( int i=0; i<100; i++ ) { ... }
and it will compile.
 解决方案 
As the problem is fixed in Java 7, it is probably a bug in the Java 6 compiler.
                        
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