Also change some internal variables to bool and change return type of
compute_alignments to void.

gcc/ChangeLog:

    * output.h (leaf_function_p): Change return type from int to bool.
    (final_forward_branch_p): Ditto.
    (only_leaf_regs_used): Ditto.
    (maybe_assemble_visibility): Ditto.
    * varasm.h (supports_one_only): Ditto.
    * rtl.h (compute_alignments): Change return type from int to void.
    * final.cc (app_on): Change return type from int to bool.
    (compute_alignments): Change return type from int to void
    and adjust function body accordingly.
    (shorten_branches):  Change "something_changed" variable
    type from int to bool.
    (leaf_function_p):  Change return type from int to bool
    and adjust function body accordingly.
    (final_forward_branch_p): Ditto.
    (only_leaf_regs_used): Ditto.
    * varasm.cc (contains_pointers_p): Change return type from
    int to bool and adjust function body accordingly.
    (compare_constant): Ditto.
    (maybe_assemble_visibility): Ditto.
    (supports_one_only): Ditto.

Bootstrapped and regression tested on x86_64-linux-gnu {,-m32}.

Uros.