flags.h: Add flag_eliminate_unused_debug_types.

        * flags.h: Add flag_eliminate_unused_debug_types.
        * toplev.c: Add flag_eliminate_unused_debug_types.
        (f_options): Add -feliminate-unused-debug-types.
        * dwarf2out.c (struct file_table): Add emitted member.
        (splice_child_die): Fix the parent pointer for the child being
        spliced.
        (lookup_filename): Maintain file_table.emitted array.  Don't
        output .file directive here.
        (maybe_emit_file): (new)
        (init_file_table): Set up file_table.emitted.
        (dwarf2out_source_line): Use maybe_emit_file.
        (dwarf2out_start_source_file): Use maybe_emit_file.
        (dwarf2out_init): Use maybe_emit_file.
        (prune_unused_types_walk_attribs): (new)
        (prune_unused_types_mark): (new)
        (prune_unused_types_walk): (new)
        (prune_unused_types_prune): (new)
        (prune_unused_types): (new)
        (dwarf2out_finish): Call prune_unused_types if
        flag_eliminate_unused_debug_types is set.
        * doc/invoke.texi (Option Summary): Add
        -feliminate-unused-debug-types.
        (Debugging Options): Likewise.

From-SVN: r63588

gcc/ChangeLog

+2003-02-28  scott snyder  <snyder@fnal.gov>
+
+	* flags.h: Add flag_eliminate_unused_debug_types.
+	* toplev.c: Add flag_eliminate_unused_debug_types.
+	(f_options): Add -feliminate-unused-debug-types.
+	* dwarf2out.c (struct file_table): Add emitted member.
+	(splice_child_die): Fix the parent pointer for the child being
+	spliced.
+	(lookup_filename): Maintain file_table.emitted array.  Don't
+	output .file directive here.
+	(maybe_emit_file): (new)
+	(init_file_table): Set up file_table.emitted.
+	(dwarf2out_source_line): Use maybe_emit_file.
+	(dwarf2out_start_source_file): Use maybe_emit_file.
+	(dwarf2out_init): Use maybe_emit_file.
+	(prune_unused_types_walk_attribs): (new)
+	(prune_unused_types_mark): (new)
+	(prune_unused_types_walk): (new)
+	(prune_unused_types_prune): (new)
+	(prune_unused_types): (new)
+	(dwarf2out_finish): Call prune_unused_types if
+	flag_eliminate_unused_debug_types is set.
+	* doc/invoke.texi (Option Summary): Add
+	-feliminate-unused-debug-types.
+	(Debugging Options): Likewise.
+
 2003-02-28  Geoffrey Keating  <geoffk@apple.com>
 
 	* doc/invoke.texi: Change .pch to .gch.

gcc/doc/invoke.texi

@@ -258,6 +258,7 @@ in the following sections.
 -p  -pg  -print-file-name=@var{library}  -print-libgcc-file-name @gol
 -print-multi-directory  -print-multi-lib @gol
 -print-prog-name=@var{program}  -print-search-dirs  -Q @gol
+-feliminate-unused-debug-types @gol
 -save-temps  -time}
 
 @item Optimization Options
@@ -3412,6 +3413,18 @@ anything else.
 @opindex dumpspecs
 Print the compiler's built-in specs---and don't do anything else.  (This
 is used when GCC itself is being built.)  @xref{Spec Files}.
+
+@item -feliminate-unused-debug-types
+@opindex feliminate-unused-debug-types
+Normally, when producing DWARF2 output, GCC will emit debugging
+information for all types declared in a compilation
+unit, regardless of whether or not they are actually used
+in that compilation unit.  Sometimes this is useful, such as
+if, in the debugger, you want to cast a value to a type that is
+not actually used in your program (but is declared).  More often,
+however, this results in a significant amount of wasted space.
+With this option, GCC will avoid producing debug symbol output
+for types that are nowhere used in the source file being compiled.
 @end table
 
 @node Optimize Options

gcc/flags.h

@@ -641,6 +641,10 @@ extern int flag_gcse_sm;
 
 extern int flag_eliminate_dwarf2_dups;
 
+/* Nonzero means we should do unused type elimination.  */
+
+extern int flag_eliminate_unused_debug_types;
+
 /* Nonzero means to collect statistics which might be expensive
    and to print them when we are done.  */
 extern int flag_detailed_statistics;

gcc/toplev.c

@@ -378,6 +378,10 @@ tree current_function_func_begin_label;
 
 int flag_eliminate_dwarf2_dups = 0;
 
+/* Nonzero if doing unused type elimination.  */
+
+int flag_eliminate_unused_debug_types = 0;
+
 /* Nonzero if generating code to do profiling.  */
 
 int profile_flag = 0;
@@ -999,6 +1003,8 @@ static const lang_independent_options f_options[] =
 {
   {"eliminate-dwarf2-dups", &flag_eliminate_dwarf2_dups, 1,
    N_("Perform DWARF2 duplicate elimination") },
+  {"eliminate-unused-debug-types", &flag_eliminate_unused_debug_types, 1,
+   N_("Perform unused type elimination in debug info") },
   {"float-store", &flag_float_store, 1,
    N_("Do not store floats in registers") },
   {"defer-pop", &flag_defer_pop, 1,