accept and ignore __gcc_tdiag__ so we don't produce warnings building mainline GCC, PR6542
accept and ignore __gcc_tdiag__ so we don't produce warnings
building mainline GCC, PR6542


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@98661 91177308-0d34-0410-b5e6-96231b3b80d8

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