From jdk7 build logs:

"../../../src/share/native/sun/awt/../java2d/opengl/OGLBlitLoops.c", line 771: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLBufImgOps.c", line 750: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLContext.c", line 986: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLFuncs.c", line 124: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLMaskBlit.c", line 93: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLMaskFill.c", line 163: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLPaints.c", line 923: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLRenderQueue.c", line 762: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLRenderer.c", line 329: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLSurfaceData.c", line 588: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLTextRenderer.c", line 1214: warning: empty translation unit
"../../../src/share/native/sun/awt/../java2d/opengl/OGLVertexCache.c", line 288: warning: empty translation unit