gcc 4.6 doesn't recognise -export-dynamic option

Need support for building hotspot with gcc 4.6. gcc 4.6 changed how arguments are handled. It now treats -export-dynamic as it treats any other -efoo option: it thinks xport-dynamic is the entry point and passes this information to the linker. Since -export-dynamic is not passed to the linker, not all symbols will be exported by the linker. The bfd-based linker, given the invalid entry point xport-dynamic, simply ignores it. The gold linker, however, crashes causing the build to fail.

Since -export-dynamic is a linker option, the correct way to pass it is using -Wl,-export-dynamic (or -Xlinker -export-dynamic). We have had this patch in IcedTea6 for a while now, but it would be nice if this was in OpenJDK too.