diff --git a/gcc/doc/gm2.texi b/gcc/doc/gm2.texi
index 19b864573c1..b38d6a15de0 100644
--- a/gcc/doc/gm2.texi
+++ b/gcc/doc/gm2.texi
@@ -466,10 +466,39 @@ this option forces the use of the static version.
 @c Modula-2 Joined
 @c set all location values to a specific value (internal switch)
 
-@c fm2-debug-trace=
-@c Modula-2 Joined
-@c turn on trace debugging using a comma separated list:
-@c line,token,quad,all.
+@item -fm2-debug-trace=
+turn on trace debugging using a comma separated list:
+@samp{line,token,quad,all}.  This is an internal command line option.
+
+@item -fm2-dump=
+enable dumping of modula-2 internal representation of data structures
+using a comma separated list.  The list can contain:
+@samp{quad,gimple,decl,all}.
+
+@item -fm2-dump-decl=@file{filestem}
+dump the modula-2 representation of a symbol to the @file{filestem}
+specified.  This option only takes effect if the
+@samp{-fm2-dump-filter} is specified.
+
+@item -fm2-dump-gimple=@file{filestem}
+dump modula-2 gimple representation to the @file{filestem} specified.
+
+@item -fm2-dump-quad=@file{filestem}
+dump quadruple representation to the @file{filestem} specified.
+
+@item -fm2-dump-filter=@samp{rules}
+filter the language dumps @samp{-fdump-lang-decl},
+@samp{-fdump-lang-gimple} and@samp{-fdump-lang-quad}
+on @samp{rules}.  @samp{rules} must be a comma
+separated list which can take three forms: the full decl textual name
+of a procedure, @samp{[libname.]module.ident} or
+@samp{[filename:]module.ident}.  This is an internal command line
+option.  Currently it only filters on procedure names and regexp
+matching is not implemented.  Three examples of its use following
+the previous forms could be:
+@code{-fm2-dump-filter=_M2_hello_init},
+@code{-fm2-dump-filter=m2pim.StrIO.WriteString} and
+@code{-fm2-dump-filter=StrLib.mod:StrIO.WriteString}.
 
 @item -fm2-g
 improve the debugging experience for new programmers at the expense
@@ -487,7 +516,7 @@ specify the module mangled prefix name for all modules in the
 following include paths.
 
 @item -fm2-pathnameI
-for internal use only: used by the driver to copy the user facing -I
+for internal use only: used by the driver to copy the user facing @samp{-I}
 option.
 
 @item -fm2-plugin
diff --git a/gcc/m2/gm2-compiler/M2AsmUtil.def b/gcc/m2/gm2-compiler/M2AsmUtil.def
index c23992e7811..9077c45b582 100644
--- a/gcc/m2/gm2-compiler/M2AsmUtil.def
+++ b/gcc/m2/gm2-compiler/M2AsmUtil.def
@@ -29,9 +29,7 @@ DEFINITION MODULE M2AsmUtil ;
                 to their equivalent representation in ASM format.
 *)
 
-FROM DynamicStrings IMPORT String ;
 FROM NameKey IMPORT Name ;
-EXPORT QUALIFIED GetFullSymName, GetFullScopeAsmName ;
 
 
 (*
diff --git a/gcc/m2/gm2-compiler/M2LangDump.mod b/gcc/m2/gm2-compiler/M2LangDump.mod
index ec3522b62dd..e65f5b040a5 100644
--- a/gcc/m2/gm2-compiler/M2LangDump.mod
+++ b/gcc/m2/gm2-compiler/M2LangDump.mod
@@ -31,7 +31,7 @@ FROM DynamicStrings IMPORT String, Length, InitString, Mark, Slice, EqualArray,
 FROM SymbolTable IMPORT NulSym,
                         GetSymName, GetLibName,
                         GetScope, GetModuleScope, GetMainModule, GetDeclaredMod,
-                        GetLocalSym,
+                        GetLocalSym, FinalSymbol,
                         IsInnerModule,
                         IsVar,
                         IsProcedure,
@@ -43,15 +43,17 @@ FROM SymbolTable IMPORT NulSym,
 FROM M2Options IMPORT GetM2DumpFilter, GetDumpDir, GetDumpQuadFilename,
                       GetDumpDeclFilename, GetDumpGimpleFilename ;
 
+FROM M2AsmUtil IMPORT GetFullSymName ;
 FROM M2GCCDeclare IMPORT IncludeDumpSymbol ;
 FROM FormatStrings IMPORT Sprintf0, Sprintf1 ;
 FROM NameKey IMPORT Name, GetKey, MakeKey, makekey, KeyToCharStar, NulName ;
-FROM SymbolConversion IMPORT Gcc2Mod, Mod2Gcc ;
+FROM SymbolConversion IMPORT Gcc2Mod, Mod2Gcc, GccKnowsAbout ;
 FROM M2AsmUtil IMPORT GetFullScopeAsmName ;
 FROM M2LexBuf IMPORT FindFileNameFromToken ;
 FROM M2Printf IMPORT fprintf0, fprintf1, printf0, printf1, printf2 ;
 FROM M2Error IMPORT InternalError ;
 FROM M2Batch IMPORT Get ;
+FROM m2misc IMPORT warning_m2_dump_filter ;
 FROM StrLib IMPORT StrLen ;
 FROM libc IMPORT printf ;
 
@@ -147,12 +149,27 @@ END CloseDumpDecl ;
 
 
 (*
-   AddRuleTextDump -
+   AddRuleTextDump - filter on the textual name given to GCC.
 *)
 
 PROCEDURE AddRuleTextDump (rule: String) ;
+VAR
+   sym      : CARDINAL ;
+   key      : Name ;
+   seenMatch: BOOLEAN ;
 BEGIN
-
+   sym := 1 ;
+   seenMatch := FALSE ;
+   key := makekey (string (rule)) ;
+   WHILE sym <= FinalSymbol () DO
+      IF IsProcedure (sym) AND (key = GetFullSymName (sym))
+      THEN
+         IncludeDumpSymbol (sym) ;
+         seenMatch := TRUE
+      END ;
+      INC (sym)
+   END ;
+   CheckRuleMatch (seenMatch, rule)
 END AddRuleTextDump ;
 
 
@@ -183,8 +200,10 @@ BEGIN
    END ;
    idstr := Slice (rule, start, 0) ;
    sym := GetLocalSym (modsym, makekey (string (idstr))) ;
-   IF sym # NulSym
+   IF sym = NulSym
    THEN
+      CheckRuleMatch (FALSE, rule)
+   ELSE
       IncludeDumpSymbol (sym)
    END
 END AddRuleScopeQualidentDump ;
@@ -227,18 +246,133 @@ BEGIN
 END AddRuleScopeDump ;
 
 
+(*
+   GenQualidentSymString - returns the qualified sym string (including
+                           any nested procedure and modules).
+*)
+
+PROCEDURE GenQualidentSymString (sym: CARDINAL) : String ;
+VAR
+   identstr,
+   qualidentstr: String ;
+BEGIN
+   qualidentstr := InitStringCharStar (KeyToCharStar (GetSymName (sym))) ;
+   WHILE GetScope (sym) # NulSym DO
+      sym := GetScope (sym) ;
+      identstr := InitStringCharStar (KeyToCharStar (GetSymName (sym))) ;
+      ConCatChar (identstr, '.') ;
+      qualidentstr := ConCat (identstr, Mark (qualidentstr))
+   END ;
+   RETURN qualidentstr
+END GenQualidentSymString ;
+
+
+(*
+   IdentQualidentMatch - return TRUE if sym name matches symstr.
+*)
+
+PROCEDURE IdentQualidentMatch (sym: CARDINAL; symstr: String) : BOOLEAN ;
+VAR
+   success     : BOOLEAN ;
+   qualidentstr: String ;
+BEGIN
+   qualidentstr := GenQualidentSymString (sym) ;
+   success := Equal (qualidentstr, symstr) ;
+   qualidentstr := KillString (qualidentstr) ;
+   RETURN success
+END IdentQualidentMatch ;
+
+
+(*
+   IsRuleFilenameMatch - return TRUE if rule matches sym.
+*)
+
+PROCEDURE IsRuleFilenameMatch (rule: String; sym: CARDINAL) : BOOLEAN ;
+VAR
+   fname,
+   modstr,
+   symstr,
+   filename: String ;
+   tokenno : CARDINAL ;
+   dot,
+   colon   : INTEGER ;
+   success : BOOLEAN ;
+BEGIN
+   tokenno := GetDeclaredMod (sym) ;
+   filename := FindFileNameFromToken (tokenno, 0) ;
+   fname := NIL ;
+   symstr := NIL ;
+   modstr := NIL ;
+   success := FALSE ;
+   colon := Index (rule, ':', 0) ;
+   IF colon > 0
+   THEN
+      fname := Slice (rule, 0, colon) ;
+      IF Equal (fname, filename)
+      THEN
+         IF INTEGER (Length (rule)) > colon
+         THEN
+            symstr := Slice (rule, colon + 1, 0) ;
+            dot := ReverseIndex (symstr, '.', -1) ;
+            IF dot >= 0
+            THEN
+               success := IdentQualidentMatch (sym, symstr)
+            ELSE
+               success := GetSymName (sym) = makekey (string (symstr))
+            END
+         END
+      END
+   END ;
+   fname := KillString (fname) ;
+   modstr := KillString (modstr) ;
+   symstr := KillString (symstr) ;
+   RETURN success
+END IsRuleFilenameMatch ;
+
+
+(*
+   CheckRuleMatch - issue a warning if seenMatch is FALSE and this is the first time
+                    the rule is matched.
+*)
+
+PROCEDURE CheckRuleMatch (seenMatch: BOOLEAN; rule: String) ;
+VAR
+   message: String ;
+BEGIN
+   IF (NoOfDeclDumps = 1) AND (NOT seenMatch)
+   THEN
+      message := InitString ("no symbol matching: %qs has been found when applying the dump filter") ;
+      warning_m2_dump_filter (string (message), string (rule));
+   END
+END CheckRuleMatch ;
+
+
 (*
    AddRuleFilenameDump -
 *)
 
 PROCEDURE AddRuleFilenameDump (rule: String) ;
+VAR
+   sym      : CARDINAL ;
+   seenMatch: BOOLEAN ;
 BEGIN
-
+   sym := 1 ;
+   seenMatch := FALSE ;
+   WHILE sym <= FinalSymbol () DO
+      IF IsProcedure (sym) AND IsRuleFilenameMatch (rule, sym)
+      THEN
+         IncludeDumpSymbol (sym) ;
+         seenMatch := TRUE
+      END ;
+      INC (sym)
+   END ;
+   CheckRuleMatch (seenMatch, rule)
 END AddRuleFilenameDump ;
 
 
 (*
-   AddRuleSymToDump -
+   AddRuleSymToDump - call appropriate sub rule.  FileName if : present.
+                      Scope if . present otherwise assume a text rule.
 *)
 
 PROCEDURE AddRuleSymToDump (rule: String) ;
diff --git a/gcc/m2/gm2-gcc/m2misc.cc b/gcc/m2/gm2-gcc/m2misc.cc
index df77f32b58d..1d337ffcb2f 100644
--- a/gcc/m2/gm2-gcc/m2misc.cc
+++ b/gcc/m2/gm2-gcc/m2misc.cc
@@ -23,6 +23,7 @@ along with GNU Modula-2; see the file COPYING3.  If not see
 
 #include "../m2-tree.h"
 #include "tree-iterator.h"
+#include "opts.h"
 
 #define m2misc_c
 #include "m2block.h"
@@ -70,3 +71,12 @@ m2misc_printStmt (void)
   if (m2block_cur_stmt_list () != NULL)
     debug_tree (m2block_cur_stmt_list ());
 }
+
+/* warning_m2_dump_filter issue a warning relating to the
+   -fm2_dump_filter=rule option.  */
+
+void
+m2misc_warning_m2_dump_filter (const char *message, const char *rule)
+{
+  warning (OPT_fm2_dump_filter_, message, rule);
+}
diff --git a/gcc/m2/gm2-gcc/m2misc.def b/gcc/m2/gm2-gcc/m2misc.def
index 26b0e4448f3..77fd2833f64 100644
--- a/gcc/m2/gm2-gcc/m2misc.def
+++ b/gcc/m2/gm2-gcc/m2misc.def
@@ -24,10 +24,9 @@ DEFINITION MODULE FOR "C" m2misc ;
 FROM m2tree IMPORT Tree ;
 FROM SYSTEM IMPORT ADDRESS ;
 
-
 PROCEDURE DebugTree (t: Tree) ;
 PROCEDURE error (message: ARRAY OF CHAR) ;
 PROCEDURE cerror (message: ADDRESS) ;
-
+PROCEDURE warning_m2_dump_filter (message, rule: ADDRESS) ;
 
 END m2misc.
diff --git a/gcc/m2/gm2-gcc/m2misc.h b/gcc/m2/gm2-gcc/m2misc.h
index f0aa82e2eed..22139841ed0 100644
--- a/gcc/m2/gm2-gcc/m2misc.h
+++ b/gcc/m2/gm2-gcc/m2misc.h
@@ -41,6 +41,7 @@ EXTERN void m2misc_printStmt (void);
 EXTERN void m2misc_DebugTreeChain (tree t);
 EXTERN void m2misc_cerror (const char *message);
 EXTERN void m2misc_error (const char *message);
+EXTERN void m2misc_warning_m2_dump_filter (const char *message, const char *rule);
 
 #undef EXTERN
 #endif /* m2misc_h.  */
diff --git a/gcc/m2/gm2-gcc/m2pp.cc b/gcc/m2/gm2-gcc/m2pp.cc
index ce004b771a6..acff6cf2e21 100644
--- a/gcc/m2/gm2-gcc/m2pp.cc
+++ b/gcc/m2/gm2-gcc/m2pp.cc
@@ -35,6 +35,12 @@ along with GNU Modula-2; see the file COPYING3.  If not see
 #include "m2pp.h"
 
 #define GM2
+/* VERBOSE_TYPE_DESC enables type descriptions to be generated in the
+   assignment and during variable declarations.  It generates
+   moderately ugly output, although the assignment type information
+   can be useful when tracking down non gimple complient trees (during
+   assignment).  */
+#undef VERBOSE_TYPE_DESC
 
 const char *m2pp_dump_description[M2PP_DUMP_END] =
 {
@@ -898,6 +904,7 @@ m2pp_identifier (pretty *s, tree t)
           else
             snprintf (name, 100, "D_%u", DECL_UID (t));
           m2pp_print (s, name);
+#ifdef VERBOSE_TYPE_DESC
 	  if (TREE_TYPE (t) != NULL_TREE)
 	    {
 	      m2pp_needspace (s);
@@ -905,12 +912,11 @@ m2pp_identifier (pretty *s, tree t)
 	      m2pp_needspace (s);
 	      m2pp_simple_type (s, TREE_TYPE (t));
 	      m2pp_needspace (s);
-#if 0
 	      m2pp_type_lowlevel (s, TREE_TYPE (t));
 	      m2pp_needspace (s);
-#endif
 	      m2pp_print (s, "*)");
 	    }
+#endif
         }
     }
 }
@@ -1842,11 +1848,13 @@ m2pp_constructor (pretty *s, tree t)
     m2pp_print (s, ", ");
   }
   m2pp_print (s, "}");
+#ifdef VERBOSE_TYPE_DESC
   m2pp_print (s, "(* type: ");
   setindent (s, getindent (s) + 8);
   m2pp_type (s, TREE_TYPE (t));
   setindent (s, getindent (s) - 8);
   m2pp_print (s, " *)\n");
+#endif
 }
 
 /* m2pp_complex_expr handle GCC complex_expr tree.  */
@@ -2569,15 +2577,20 @@ m2pp_assignment (pretty *s, tree t)
   int o;
 
   m2pp_begin (s);
-
+#ifdef VERBOSE_TYPE_DESC
   /* Print the types of des and expr.  */
+  m2pp_print (s, "(*");
+  m2pp_needspace (s);
   m2pp_type (s, TREE_TYPE (TREE_OPERAND (t, 0)));
   m2pp_needspace (s);
   m2pp_print (s, ":=");
   m2pp_needspace (s);
   m2pp_type (s, TREE_TYPE (TREE_OPERAND (t, 1)));
   m2pp_needspace (s);
-  m2pp_print (s, ";\n");
+  m2pp_print (s, ";");
+  m2pp_needspace (s);
+  m2pp_print (s, "*)\n");
+#endif
   /* Print the assignment statement.  */
   m2pp_designator (s, TREE_OPERAND (t, 0));
   m2pp_needspace (s);
diff --git a/gcc/m2/gm2-lang.cc b/gcc/m2/gm2-lang.cc
index e31a6c437ec..b3c3c017cc9 100644
--- a/gcc/m2/gm2-lang.cc
+++ b/gcc/m2/gm2-lang.cc
@@ -42,8 +42,6 @@ Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
 #include "convert.h"
 #include "rtegraph.h"
 
-#undef ENABLE_M2DUMP_ALL
-
 static void write_globals (void);
 
 static int insideCppArgs = FALSE;
@@ -521,7 +519,6 @@ gm2_langhook_handle_option (
     case OPT_fm2_debug_trace_:
       M2Options_SetM2DebugTraceFilter (value, arg);
       return 1;
-#ifdef ENABLE_M2DUMP_ALL
     case OPT_fm2_dump_:
       return M2Options_SetM2Dump (value, arg);
     case OPT_fm2_dump_decl_:
@@ -536,7 +533,6 @@ gm2_langhook_handle_option (
     case OPT_fm2_dump_filter_:
       M2Options_SetM2DumpFilter (value, arg);
       return 1;
-#endif
     case OPT_Wall:
       M2Options_SetWall (value);
       return 1;
diff --git a/gcc/m2/lang.opt b/gcc/m2/lang.opt
index 1c165317959..3fc84a12d94 100644
--- a/gcc/m2/lang.opt
+++ b/gcc/m2/lang.opt
@@ -134,6 +134,26 @@ fm2-debug-trace=
 Modula-2 Joined
 turn on internal debug tracing for quad,token,line,all (internal switch)
 
+fm2-dump=
+Modula-2 Joined
+dump Modula-2 internal intemediate representation specified by: all,quad,decl,gimple
+
+fm2-dump-decl=
+Modula-2 Joined
+dump Modula-2 decls to the filename stem specified
+
+fm2-dump-gimple=
+Modula-2 Joined
+dump Modula-2 gimple to the filename stem specified
+
+fm2-dump-quad=
+Modula-2 Joined
+dump Modula-2 quads to the filename stem specified
+
+fm2-dump-filter=
+Modula-2 Joined
+filter the language dump using a comma separated list of procedures and modules
+
 fm2-g
 Modula-2
 generate extra nops to improve debugging, producing an instruction for every code related keyword