2011-06-08  Tobias Burnus  <burnus@net-b.de>

        PR fortran/18918
        * gfortran.h (gfc_statement): Add ST_LOCK and ST_UNLOCK.
        (gfc_exec_op): Add EXEC_LOCK and EXEC_UNLOCK.
        (gfc_code): Add expr4.
        * match.h (gfc_match_lock, gfc_match_unlock): New prototypes.
        * match.c (gfc_match_lock, gfc_match_unlock,
        lock_unlock_statement): New functions.
        (sync_statement): Bug fix, avoiding double freeing.
        (gfc_match_if): Handle LOCK/UNLOCK statement.
        * parse.c (decode_statement, next_statement,
        gfc_ascii_statement): Ditto.
        * st.c (gfc_free_statement): Handle LOCK and UNLOCK.
        * resolve.c (resolve_lock_unlock): New function.
        (resolve_code): Call it.
        * dump-parse-tree.c (show_code_node): Handle LOCK/UNLOCK.
        * frontend-passes.c (gfc_code_walker): Optimize gfc_code's expr4.

2011-06-08  Tobias Burnus  <burnus@net-b.de>

        PR fortran/18918
        * gfortran.dg/coarray_lock_1.f90: New.
        * gfortran.dg/coarray_lock_2.f90: New.

From-SVN: r174796