diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index ff0e63962a8412655fd05bb66e4b0364ede6115d..ad0ffcc443ee50acd120f9bfaeedb768ddb977bc 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,16 @@
+2008-01-17  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR fortran/33375
+	* symbol.c (free_common_tree): Renamed to ...
+	(gfc_free_common_tree): This.  Remove static.
+	(gfc_free_namespace): Updated.
+
+	* gfortran.h (gfc_free_common_tree): New.
+
+	* match.c (gfc_match_common): Call gfc_free_common_tree () with
+	gfc_current_ns->common_root and set gfc_current_ns->common_root
+	to NULL on syntax error.
+
 2008-01-18  Richard Sandiford  <rsandifo@nildram.co.uk>
 
 	PR fortran/34686
diff --git a/gcc/fortran/gfortran.h b/gcc/fortran/gfortran.h
index aac1f821334c0f184350c6cfa1d7e761eb3b01aa..d5f00737d3db4dba6e9b0692cddb0f6832fc20a4 100644
--- a/gcc/fortran/gfortran.h
+++ b/gcc/fortran/gfortran.h
@@ -2137,6 +2137,7 @@ int gfc_symbols_could_alias (gfc_symbol *, gfc_symbol *);
 void gfc_undo_symbols (void);
 void gfc_commit_symbols (void);
 void gfc_commit_symbol (gfc_symbol *);
+void gfc_free_common_tree (gfc_symtree *);
 void gfc_free_namespace (gfc_namespace *);
 
 void gfc_symbol_init_2 (void);
diff --git a/gcc/fortran/match.c b/gcc/fortran/match.c
index ad636f93f3d6709e8a25a65e4914251f2dce7589..f21748c1b9ae4cdd395a9a1a4b5fd952209c00c6 100644
--- a/gcc/fortran/match.c
+++ b/gcc/fortran/match.c
@@ -2951,6 +2951,8 @@ done:
   return MATCH_YES;
 
 syntax:
+  gfc_free_common_tree (gfc_current_ns->common_root);
+  gfc_current_ns->common_root = NULL;
   gfc_syntax_error (ST_COMMON);
 
 cleanup:
diff --git a/gcc/fortran/symbol.c b/gcc/fortran/symbol.c
index 72008066990ccf4a00399b6f777816b971ef8112..a50ed261141c014a87adbf1d4d56be220d259697 100644
--- a/gcc/fortran/symbol.c
+++ b/gcc/fortran/symbol.c
@@ -2726,14 +2726,14 @@ gfc_commit_symbol (gfc_symbol *sym)
 /* Recursive function that deletes an entire tree and all the common
    head structures it points to.  */
 
-static void
-free_common_tree (gfc_symtree * common_tree)
+void
+gfc_free_common_tree (gfc_symtree * common_tree)
 {
   if (common_tree == NULL)
     return;
 
-  free_common_tree (common_tree->left);
-  free_common_tree (common_tree->right);
+  gfc_free_common_tree (common_tree->left);
+  gfc_free_common_tree (common_tree->right);
 
   gfc_free (common_tree);
 }  
@@ -2863,7 +2863,7 @@ gfc_free_namespace (gfc_namespace *ns)
 
   free_sym_tree (ns->sym_root);
   free_uop_tree (ns->uop_root);
-  free_common_tree (ns->common_root);
+  gfc_free_common_tree (ns->common_root);
 
   for (cl = ns->cl_list; cl; cl = cl2)
     {