Index: tree-pass.h
===================================================================
--- tree-pass.h (revision 188966)
+++ tree-pass.h (working copy)
@@ -85,7 +85,6 @@ enum tree_dump_index
 #define TDF_CSELIB     (1 << 23)       /* Dump cselib details.  */
 #define TDF_SCEV       (1 << 24)       /* Dump SCEV details.  */

-
 /* In tree-dump.c */

 extern char *get_dump_file_name (int);

please avoid whitespace-only changes (also elsewhere).

 /* Global variables used to communicate with passes.  */
 extern FILE *dump_file;
+extern FILE *alt_dump_file;
 extern int dump_flags;
+extern int opt_info_flags;

so I expected the primary dump_file to be controlled with dump_flags,
or with a (cached) translation of them to a primary_opt_info_flags.

Index: gimple-pretty-print.h
===================================================================
--- gimple-pretty-print.h       (revision 188966)
+++ gimple-pretty-print.h       (working copy)
@@ -31,6 +31,6 @@ extern void debug_gimple_seq (gimple_seq);
 extern void print_gimple_seq (FILE *, gimple_seq, int, int);
 extern void print_gimple_stmt (FILE *, gimple, int, int);
 extern void print_gimple_expr (FILE *, gimple, int, int);
-extern void dump_gimple_stmt (pretty_printer *, gimple, int, int);
+extern void print_gimple_stmt_1 (pretty_printer *, gimple, int, int);

I'd call this pp_gimple_stmt instead.

@@ -1418,6 +1419,16 @@ init_branch_prob (void)
 void
 end_branch_prob (void)
 {
+  end_branch_prob_1 (dump_file);
+  end_branch_prob_1 (alt_dump_file);
+}
+
+/* Helper function for file-level cleanup for DUMP_FILE after
+   branch-prob processing is completed. */
+
+static void
+end_branch_prob_1 (FILE *dump_file)
+{
   if (dump_file)
     {
       fprintf (dump_file, "\n");

That change looks odd ;)  Can you instead use the new dump_printf
interface?  (side-note: we should not need to export alt_dump_file at all!)

@@ -2166,10 +2177,6 @@ ftree-vect-loop-version
 Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
 Enable loop versioning when doing loop vectorization on trees

-ftree-vectorizer-verbose=
-Common RejectNegative Joined UInteger
--ftree-vectorizer-verbose=<number>     Set the verbosity level of the
vectorizer
-

we need to preserve old switches for backward compatibility, I suggest
to alias it to -fopt-info for now.

@@ -13909,7 +13909,7 @@ unmentioned_reg_p (rtx equiv, rtx expr)
 }
 ^L
 DEBUG_FUNCTION void
-dump_combine_stats (FILE *file)
+print_combine_stats (FILE *file)

see above, debug_combine_stats.

Index: system.h
===================================================================
--- system.h    (revision 188966)
+++ system.h    (working copy)
@@ -669,6 +669,7 @@ extern int vsnprintf(char *, size_t, const char *,
    except, maybe, something to the dump file.  */
 #ifdef BUFSIZ
 extern FILE *dump_file;
+extern FILE *alt_dump_file;

see above - we should not need to export this (nor opt_info_flags).