RFR: 8329086: Clean up java.desktop native compilation

[Erik Joelsson]

On Tue, 26 Mar 2024 19:19:14 GMT, Phil Race <prr at openjdk.org> wrote:

>> This is a follow-up on [JDK-8328680](https://bugs.openjdk.org/browse/JDK-8328680), making the same kind of cleanup to java.desktop. Some code needed more special treatment here, so there is some additional effects outside of the modules/java.desktop directory. The code was also in worse shape than other modules, so some additional changes to the build logic where needed.
>
> make/modules/java.desktop/lib/Awt2dLibraries.gmk line 107:
> 
>> 105: 
>> 106: LIBAWT_CFLAGS += -D__MEDIALIB_OLD_NAMES -D__USE_J2D_NAMES $(X_CFLAGS)
>> 107: 
> 
> Why is X_CFLAGS no longer needed ?

It's just moved down.

> make/modules/java.desktop/lib/Awt2dLibraries.gmk line 569:
> 
>> 567: LIBJAWT_EXTRA_HEADER_DIRS := \
>> 568:     include \
>> 569:     #
> 
> A syntax question - what does the trailing # do / mean here ?
> Superficially I'd expect this to expand to "include #"
> which means there'd be a # embedded when you append the other folders below ..

The `#` marks a comment, so will basically be ignored. We use this construct to define easy to read lists where every element can have a trailing ``, including the last. This makes it easier to add or remove items in the list without causing diffs in unrelated lines. In this case the list has only one element, so I would suggest just using a single line assignment. OTOH, it seems Magnus chose to use this construct for uniformity with all other HEADER and SRC lists.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/18486#discussion_r1540172045
PR Review Comment: https://git.openjdk.org/jdk/pull/18486#discussion_r1540221259