This package should drop -Werror flag, from the build log: /home/ago/log/build/dev-java/icedtea-6.1.12.0:20130204-094152.log:g++ -DLINUX -D_GNU_SOURCE -DAMD64 -DPRODUCT -I. -I/var/tmp/portage/dev-java/icedtea-6.1.12.0/work/icedtea6-1.12.0/openjdk-ecj/hotspot/src/share/vm -I/var/tmp/portage/dev-java/icedtea-6.1.12.0/work/icedtea6-1.12.0/openjdk-ecj/hotspot/src/share/vm/prims -I/var/tmp/portage/dev-java/icedtea-6.1.12.0/work/icedtea6-1.12.0/openjdk-ecj/hotspot/src/cpu/x86/vm -I/var/tmp/portage/dev-java/icedtea-6.1.12.0/work/icedtea6-1.12.0/openjdk-ecj/hotspot/src/os/linux/vm -I/var/tmp/portage/dev-java/icedtea-6.1.12.0/work/icedtea6-1.12.0/openjdk-ecj/hotspot/src/os_cpu/linux_x86/vm -I../generated -DHOTSPOT_RELEASE_VERSION="\"20.0-b12\"" -DHOTSPOT_BUILD_TARGET="\"product\"" -DHOTSPOT_BUILD_USER="\"root\"" -DHOTSPOT_LIB_ARCH=\"amd64\" -DJRE_RELEASE_VERSION="\"1.6.0_27-b27\"" -DHOTSPOT_VM_DISTRO="\"OpenJDK\"" -DDERIVATIVE_ID="\"IcedTea6 1.12.0\"" -DDISTRIBUTION_ID="\"Built on Gentoo Base System release 2.1 (Mon Feb 4 10:42:08 CET 2013)\"" -march=native -O2 -g0 -pipe -DTARGET_OS_FAMILY_linux -DTARGET_ARCH_x86 -DTARGET_ARCH_MODEL_x86_64 -DTARGET_OS_ARCH_linux_x86 -DTARGET_OS_ARCH_MODEL_linux_x86_64 -DTARGET_COMPILER_gcc -DCOMPILER2 -DCOMPILER1 -fno-rtti -fno-exceptions -D_REENTRANT -fcheck-new -m64 -pipe -g -DTARGET_OS_FAMILY_linux -DTARGET_ARCH_x86 -DTARGET_ARCH_MODEL_x86_64 -DTARGET_OS_ARCH_linux_x86 -DTARGET_OS_ARCH_MODEL_linux_x86_64 -DTARGET_COMPILER_gcc -DCOMPILER2 -DCOMPILER1 -fpic -fno-rtti -fno-exceptions -D_REENTRANT -fcheck-new -m64 -pipe -g -O3 -fno-strict-aliasing -DVM_LITTLE_ENDIAN -D_LP64=1 -fno-omit-frame-pointer -Werror -Wpointer-arith -Wsign-compare -c -MMD -MP -MF ../generated/dependencies/ciKlass.o.d -o ciKlass.o /var/tmp/portage/dev-java/icedtea-6.1.12.0/work/icedtea6-1.12.0/openjdk-ecj/hotspot/src/share/vm/ci/ciKlass.cpp
Released in 1.13.2, updated ebuild in overlay: http://bit.ly/1f0BhnC