On Thu, 29 Aug 2024 18:44:22 GMT, Kim Barrett <kbarr...@openjdk.org> wrote:
>> Currently, we issue -Wno-unused for all files in clang, which is a rather >> big sledgehammer to get rid of some warnings that proliferate in a few areas >> of the build. >> >> We should instead leave -Wunused turned on (as done by -Wall) and use a much >> more fine-grained approach to disabling specific warnings in specific files >> or libraries. >> >> This is similar to what has been done for gcc in JDK-8339120. > > make/autoconf/flags-cflags.m4 line 266: > >> 264: # These warnings will never be turned on, since they generate too >> many >> 265: # false positives. >> 266: DISABLED_WARNINGS="unknown-warning-option unused-parameter" > > JDK-8339120 added -Wunused-const-variable=1 and -Wunused-result to gcc's > WARNINGS_ENABLE_ADDITIONAL, to "make up" for the corresponding removal of > disabling -Wunused. That isn't done here. I assume that was intentional, > probably to avoid needing more of the specific disables in this PR. That's > fine. We can do more warning option cleanups later in conjunction with > corresponding code changes. No, it was just not needed by clang. `-Wunused-result` is enabled by `-Wunused-value` which is enabled by `-Wunused` which is enabled by `-Wall`. Or something like that. I think it made sense, but the documentation was bad so you had to jump around to understand how things were related. `Wunused-const-variable=1` does not exist in clang, but whatever the closest matching thing was, was enabled as well indirectly already. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/20770#discussion_r1737153568
