RFR - JDK-8218650: LineNumberTable records for method invocations with arguments

[Remi Forax]

I don't think you need to bloat the line number table for this case because soon the NPE error message will be more precise [1]. 

Rémi 

[1] [ https://bugs.openjdk.java.net/browse/JDK-8218628 | https://bugs.openjdk.java.net/browse/JDK-8218628 ] 

> De: "Vicente Romero" <vicente.romero at oracle.com>
> À: "Eddie Aftandilian" <eaftan at google.com>
> Cc: "compiler-dev" <compiler-dev at openjdk.java.net>
> Envoyé: Mercredi 20 Février 2019 14:38:45
> Objet: Re: RFR - JDK-8218650: LineNumberTable records for method invocations
> with arguments

> On 2/19/19 8:27 PM, Eddie Aftandilian wrote:

>> Hi Vicente,

>> Thanks for the reply. Can I ask why you don't think the LNT should contain
>> entries for accesses to fields? It seems that results in incorrect line numbers
>> in certain cases. For example, consider the following code:

>> 1: class LineNumbers {
>> 2:
>> 3: static class T {
>> 4: boolean b;
>> 5: }
>> 6:
>> 7: static void doIt(boolean... values) {}
>> 8:
>> 9: public static void main(String[] args) {
>> 10: T a = new T();
>> 11: T b = null;
>> 12:
>> 13: doIt(
>> 14: a.b,
>> 15: b.b);
>> 16: }
>> 17: }

>> $ javac LineNumbers.java
>> $ java LineNumbers
>> Exception in thread "main" java.lang.NullPointerException
>> at LineNumbers.main(LineNumbers.java:13)

>> I would expect the exception to be at line 15, not 13.

> having the exception at 13 is plain bad or good enough? It seems to me that you
> want to do some automation based on the exact line where the exception was
> produced. I'm just worried that generating LNT entries for every expression
> would produce, probably unnecessarily, fluffier class files.

>> Thanks,
>> Eddie

> Thanks,
> Vicente

>> On Fri, Feb 15, 2019 at 6:46 PM Vicente Romero < [
>> mailto:vicente.romero at oracle.com | vicente.romero at oracle.com ] > wrote:

>>> Hi Eddie,

>>> Thanks for the patch. But first I'm not sure that there is a bug in the
>>> LNT. There is an entry in the LNT, I'm talking about the example at [1],
>>> for the invocation of method `id`. What we need to understand is why the
>>> stack trace is not referring to that line and is referring to line 12.
>>> In any case I don't think that the LNT should contain entries for
>>> accesses to fields.

>>> Thanks,
>>> Vicente

>>> [1] [ https://bugs.openjdk.java.net/browse/JDK-8218650 |
>>> https://bugs.openjdk.java.net/browse/JDK-8218650 ]

>>> On 2/15/19 8:37 PM, Eddie Aftandilian wrote:
>>> > Hi,

>>> > I have attached a patch for JDK-8218650, in which there are missing
>>> > line number table entries for field accesses. This is my first attempt
>>> > to contribute to OpenJDK, so I'm happy to take feedback. Please see
>>> > the attached patch.

>>>> Bug report: [ https://bugs.openjdk.java.net/browse/JDK-8218650 |
>>> > https://bugs.openjdk.java.net/browse/JDK-8218650 ]

>>> > Thanks,
>>> > Eddie Aftandilian
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