Question on -Xlint:processing

[Mark Mahieu]

I guess it's worth mentioning that -g: also used to be considered a  
valid option, but no longer is.  I found out yesterday that NetBeans  
specifies it when invoking javac.

Regards,

Mark


On 20 Aug 2008, at 21:49, Joe Darcy wrote:

> Hello.
>
> Yep, that's a bug; I've filed 6739427 "-Xlint:processing not  
> recognized as an option" to track this.  -Xlint:processing should  
> be recognized a valid option.
>
> -Joe
>
> Peng Li wrote:
>> Hi,
>>
>> I noticed that the "-Xlint:processing" javac command line option is
>> broken in the recent openjdk7.  It was never a officially documented
>> feature before, but it has been a working feature in earlier JDKs and
>> there are people using it.
>>
>> I investigated the issue and discovered several relevant facts in
>> langtools/src/share/classes/com/sun/tools/javac:
>>
>> (1) The following code assumes that Xlint:processing *is* a valid  
>> Xlint option:
>>
>>      processing/JavacProcessingEnvironment.java:
>>      ...
>>      lint = options.lint("processing");
>>
>> (2) The following code assumes that Xlint:processing is *not* a valid
>> Xlint option:
>>
>>      code/Lint.java:
>>      ...
>>      public enum LintCategory
>>
>> (3) In the old openjdk code (20071030 and earlier), all command line
>> options starting with "-Xlint:" are recogonized as valid Xlint
>> options: even "-Xlint:junkfsdjlmcasl" is OK. The relevant code is in
>>
>>      main/RecognizedOptions.java:
>>      ...
>>      new XOption(XLINT_CUSTOM,
>> "opt.Xlint.suboptlist") {
>>              public boolean matches(String s) {
>>                 return s.startsWith("-Xlint:");
>>
>>      A consequence is that, even though "-Xlint:processing" was not
>> enumerated as an valid option in code/Lint.java, it was accepted as a
>> valid Xlint option and used in
>> processing/JavacProcessingEnvironment.java
>>
>> (4) In the recent openjdk7 code, there is a change in the way valid
>> command line options are recognized:
>>
>>
>>      main/RecognizedOptions.java:
>>      ...
>>      new XOption(XLINT_CUSTOM,
>> "opt.Xlint.suboptlist",
>>           Option.ChoiceKind.ANYOF, getXLintChoices()),
>>
>>    This is apparently an improvement over the old openjdk code  
>> because
>> "-Xlint:junkfsdjlmcasl" will now be reported as an invalid option.
>> However, it also breaks all the software that uses the
>> "-Xlint:processing" feature:
>>
>>     $ javac  -Xlint:processing x.java
>>     javac: invalid flag: -Xlint:processing
>>     Usage: javac <options> <source files>
>>     use -help for a list of possible options
>>     $
>>
>> I hope this issue can be fixed in future openjdk versions.  The most
>> important question seems to be whether "-Xlint:processing" should  
>> be a
>> valid and supported option.  If yes, the problem can be fixed by
>> simply adding a line in code/Lint.java to recognize the option.  If
>> no, a clear-cut decision needs to be made and the code depending on
>> this option (for example, processing/JavacProcessingEnvironment.java)
>> should be fixed to avoid confusion for developers and users.
>>
>> Best regards,
>> Peng Li
>>
>