When enabling the jsound ERROR and TRACE reporting (see src/java.desktop/share/native/libjsound/Configure.h https://github.com/openjdk/jdk/blob/master/src/java.desktop/share/native/libjsound/Configure.h#L32 ), we run into these build warnings as errors because at some places the format specifiers do not match the number types :

/jdk/src/java.desktop/share/native/libjsound/MidiInDevice.c: In function 'Java_com_sun_media_sound_MidiInDevice_nGetTimeStamp':
/jdk/src/java.desktop/share/native/libjsound/Utilities.h:38:65: error: format '%lld' expects argument of type 'long long int', but argument 3 has type 'jlong' {aka 'long int'} [-Werror=format=]
   38 | #define ERROR1(string, p1) { fprintf(stdout, (string), (p1)); fflush(stdout); }
      | ^~~~~~~~ ~~~~
      | |
      | jlong {aka long int}
/jdk/src/java.desktop/share/native/libjsound/MidiInDevice.c:140:9: note: in expansion of macro 'ERROR1'
  140 | ERROR1("Java_com_sun_media_sound_MidiInDevice_nGetTimeStamp: MIDI_IN_GetTimeStamp returned %lld\n", ret);
      | ^~~~~~
cc1: all warnings being treated as errors
* For target support_native_java.desktop_libjsound_MidiOutDevice.o:
In file included from /jdk/src/java.desktop/share/native/libjsound/MidiOutDevice.c:40:
/jdk/src/java.desktop/share/native/libjsound/MidiOutDevice.c: In function 'Java_com_sun_media_sound_MidiOutDevice_nGetTimeStamp':
/jdk/src/java.desktop/share/native/libjsound/Utilities.h:38:65: error: format '%lld' expects argument of type 'long long int', but argument 3 has type 'jlong' {aka 'long int'} [-Werror=format=]
   38 | #define ERROR1(string, p1) { fprintf(stdout, (string), (p1)); fflush(stdout); }
      | ^~~~~~~~ ~~~~
      | |
      | jlong {aka long int}
/jdk/src/java.desktop/share/native/libjsound/MidiOutDevice.c:97:9: note: in expansion of macro 'ERROR1'
   97 | ERROR1("Java_com_sun_media_sound_MidiOutDevice_nGetTimeStamp: MIDI_IN_GetTimeStamp returned %lld\n", ret);
      | ^~~~~~
cc1: all warnings being treated as errors