build warnings

[Jonathan Gibbons]

Build folk,

The build has always generated warnings (sigh!) but right now, the 
warnings look scarier than usual.

In particular, when the build terminates, I get a couple of screenfuls 
of messages like this:

/w/jjg/work/jfm2.0/dev.8059977.sjfm/jdk/src/java.desktop/unix/native/libsplashscreen/splashscreen_sys.c: 
In function ‘SplashScreenThread’:
/w/jjg/work/jfm2.0/dev.8059977.sjfm/jdk/src/java.desktop/unix/native/libsplashscreen/splashscreen_sys.c:742:9: 
warning: ignoring return value of ‘pipe’, declared with attribute 
warn_unused_result [-Wunused-result]
      pipe(splash->controlpipe);
          ^
/w/jjg/work/jfm2.0/dev.8059977.sjfm/jdk/src/java.desktop/share/native/libsplashscreen/splashscreen_gfx_impl.c: 
In function ‘initFormat’:
/w/jjg/work/jfm2.0/dev.8059977.sjfm/jdk/src/java.desktop/share/native/libsplashscreen/splashscreen_gfx_impl.c:305:34: 
warning: ‘numBits’ may be used uninitialized in this function 
[-Wmaybe-uninitialized]
          format->shift[i] = shift + numBits - i * 8 - 8;
                                   ^

What would it take to have some sort of campaign to reduce build 
warnings like these?  We've made good progress on lint and doclint 
warnings for Java code and doc comments; what does it take to start on 
native code warnings?

-- Jon