The Full Debug Symbol (FDS) work established the use of objcopy/gobjcopy to produce symbols files as part of the build process. That work did not cover any of the requirements for cross-compilation and so when cross-compiling FDS generation is simply disabled.
Cross-compilation environments should define ALT_OBJCOPY to point to the correct tool for generating symbols and so the explicit disabling of FDS should be removed.
This is the JDK side of 8002034.
All we need do is simply change the default objcopy when cross-compiling. For native or cross-compilation this can be overridden by ALT_OBJCOPY.