On Tue, 13 May 2025 18:19:37 GMT, Harshitha Onkar <hon...@openjdk.org> wrote:
> The following line results in unused-result warning on linux/clang. > > > /java.desktop/unix/native/libawt_xawt/xawt/XToolkit.c:695:9: error: ignoring > return value of function > declared with 'warn_unused_result' attribute [-Werror,-Wunused-result] > 695 | write ( AWT_WRITEPIPE, &wakeUp_char, 1 ); > > > There are two ways to handle it > > 1) Make changes to XToolkit.c such that the warning is no longer thrown. But > throwing an error based on the result of `write ( AWT_WRITEPIPE, > &wakeUp_char, 1 );` will result in unexpected behavioral changes and the best > way to handle it is to have an empty if block with an appropriate comment. > > 2) Add unused-result to disabled warning section for clang similar to gcc - > https://github.com/openjdk/jdk/blob/d1543429ff29ca0d761b8473b3fb8621abcd226d/make/modules/java.desktop/lib/AwtLibraries.gmk#L281. > The 1st approach was picked over the 2nd since the usual recommendation is > not to add to disabled warning section unless there is no other option. > > NOTE: the fix has been tested on linux/gcc , it does need to be tested on > linux/clang. make/modules/java.desktop/lib/AwtLibraries.gmk line 281: > 279: DISABLED_WARNINGS_gcc_XlibWrapper.c := type-limits > pointer-to-int-cast, \ > 280: DISABLED_WARNINGS_gcc_XRBackendNative.c := maybe-uninitialized, \ > 281: DISABLED_WARNINGS_gcc_XToolkit.c := unused-result, \ Probably a question for build team - One thing to be noted here is that: With unused-result line removed and WITHOUT the if block changes in XToolkit.c, I expected the build to fail due to unused-result on linux/gcc but it did not. So is there any chance that this disabled warning is being added from else where for gcc ? ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/25217#discussion_r2087413125
