The optimization flags in Defs-linux.gmk are only applied for the "java"
product which means that any libraries built in the make/sun tree will be
compiled with no optimizations.
This includes, among other things, nearly all of the rendering code in the
JDK, built from directories sun/dcpr and sun/awt. The Makefile for the
medialib support library in sun/image/generic is the only directory that
manually enables the optimization flags.
Many of the subdirectories of make/java also specify "sun" as their
PRODUCT and thus are not optimized.