Revert "Re-tighten default compiler options."

This reverts commit a1a35a3e2a3b170330e3c978da7a2eab0856ff9c.
Revert "Prepare upcoming GCC 4.8 release."

This reverts commit 10b3e48df61a4ac091b0f7855862455dd66c0991.
Revert "Link PRIVATE_TARGET_FDO_LIB before shared libraries"

This reverts commit 33254f1477fb9110150809608e9d1912d05275e9.