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+/* C preprocessor macro tables for GDB.
+ Copyright 2002 Free Software Foundation, Inc.
+ Contributed by Red Hat, Inc.
+
+ This file is part of GDB.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#include "defs.h"
+#include "obstack.h"
+#include "splay-tree.h"
+#include "symtab.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "macrotab.h"
+#include "gdb_assert.h"
+#include "bcache.h"
+#include "complaints.h"
+
+
+/* The macro table structure. */
+
+struct macro_table
+{
+ /* The obstack this table's data should be allocated in, or zero if
+ we should use xmalloc. */
+ struct obstack *obstack;
+
+ /* The bcache we should use to hold macro names, argument names, and
+ definitions, or zero if we should use xmalloc. */
+ struct bcache *bcache;
+
+ /* The main source file for this compilation unit --- the one whose
+ name was given to the compiler. This is the root of the
+ #inclusion tree; everything else is #included from here. */
+ struct macro_source_file *main_source;
+
+ /* The table of macro definitions. This is a splay tree (an ordered
+ binary tree that stays balanced, effectively), sorted by macro
+ name. Where a macro gets defined more than once (presumably with
+ an #undefinition in between), we sort the definitions by the
+ order they would appear in the preprocessor's output. That is,
+ if `a.c' #includes `m.h' and then #includes `n.h', and both
+ header files #define X (with an #undef somewhere in between),
+ then the definition from `m.h' appears in our splay tree before
+ the one from `n.h'.
+
+ The splay tree's keys are `struct macro_key' pointers;
+ the values are `struct macro_definition' pointers.
+
+ The splay tree, its nodes, and the keys and values are allocated
+ in obstack, if it's non-zero, or with xmalloc otherwise. The
+ macro names, argument names, argument name arrays, and definition
+ strings are all allocated in bcache, if non-zero, or with xmalloc
+ otherwise. */
+ splay_tree definitions;
+};
+
+
+
+/* Allocation and freeing functions. */
+
+/* Allocate SIZE bytes of memory appropriately for the macro table T.
+ This just checks whether T has an obstack, or whether its pieces
+ should be allocated with xmalloc. */
+static void *
+macro_alloc (int size, struct macro_table *t)
+{
+ if (t->obstack)
+ return obstack_alloc (t->obstack, size);
+ else
+ return xmalloc (size);
+}
+
+
+static void
+macro_free (void *object, struct macro_table *t)
+{
+ gdb_assert (! t->obstack);
+ xfree (object);
+}
+
+
+/* If the macro table T has a bcache, then cache the LEN bytes at ADDR
+ there, and return the cached copy. Otherwise, just xmalloc a copy
+ of the bytes, and return a pointer to that. */
+static const void *
+macro_bcache (struct macro_table *t, const void *addr, int len)
+{
+ if (t->bcache)
+ return bcache (addr, len, t->bcache);
+ else
+ {
+ void *copy = xmalloc (len);
+ memcpy (copy, addr, len);
+ return copy;
+ }
+}
+
+
+/* If the macro table T has a bcache, cache the null-terminated string
+ S there, and return a pointer to the cached copy. Otherwise,
+ xmalloc a copy and return that. */
+static const char *
+macro_bcache_str (struct macro_table *t, const char *s)
+{
+ return (char *) macro_bcache (t, s, strlen (s) + 1);
+}
+
+
+/* Free a possibly bcached object OBJ. That is, if the macro table T
+ has a bcache, it's an error; otherwise, xfree OBJ. */
+void
+macro_bcache_free (struct macro_table *t, void *obj)
+{
+ gdb_assert (! t->bcache);
+ xfree (obj);
+}
+
+
+
+/* Macro tree keys, w/their comparison, allocation, and freeing functions. */
+
+/* A key in the splay tree. */
+struct macro_key
+{
+ /* The table we're in. We only need this in order to free it, since
+ the splay tree library's key and value freeing functions require
+ that the key or value contain all the information needed to free
+ themselves. */
+ struct macro_table *table;
+
+ /* The name of the macro. This is in the table's bcache, if it has
+ one. */
+ const char *name;
+
+ /* The source file and line number where the definition's scope
+ begins. This is also the line of the definition itself. */
+ struct macro_source_file *start_file;
+ int start_line;
+
+ /* The first source file and line after the definition's scope.
+ (That is, the scope does not include this endpoint.) If end_file
+ is zero, then the definition extends to the end of the
+ compilation unit. */
+ struct macro_source_file *end_file;
+ int end_line;
+};
+
+
+/* Return the #inclusion depth of the source file FILE. This is the
+ number of #inclusions it took to reach this file. For the main
+ source file, the #inclusion depth is zero; for a file it #includes
+ directly, the depth would be one; and so on. */
+static int
+inclusion_depth (struct macro_source_file *file)
+{
+ int depth;
+
+ for (depth = 0; file->included_by; depth++)
+ file = file->included_by;
+
+ return depth;
+}
+
+
+/* Compare two source locations (from the same compilation unit).
+ This is part of the comparison function for the tree of
+ definitions.
+
+ LINE1 and LINE2 are line numbers in the source files FILE1 and
+ FILE2. Return a value:
+ - less than zero if {LINE,FILE}1 comes before {LINE,FILE}2,
+ - greater than zero if {LINE,FILE}1 comes after {LINE,FILE}2, or
+ - zero if they are equal.
+
+ When the two locations are in different source files --- perhaps
+ one is in a header, while another is in the main source file --- we
+ order them by where they would appear in the fully pre-processed
+ sources, where all the #included files have been substituted into
+ their places. */
+static int
+compare_locations (struct macro_source_file *file1, int line1,
+ struct macro_source_file *file2, int line2)
+{
+ /* We want to treat positions in an #included file as coming *after*
+ the line containing the #include, but *before* the line after the
+ include. As we walk up the #inclusion tree toward the main
+ source file, we update fileX and lineX as we go; includedX
+ indicates whether the original position was from the #included
+ file. */
+ int included1 = 0;
+ int included2 = 0;
+
+ /* If a file is zero, that means "end of compilation unit." Handle
+ that specially. */
+ if (! file1)
+ {
+ if (! file2)
+ return 0;
+ else
+ return 1;
+ }
+ else if (! file2)
+ return -1;
+
+ /* If the two files are not the same, find their common ancestor in
+ the #inclusion tree. */
+ if (file1 != file2)
+ {
+ /* If one file is deeper than the other, walk up the #inclusion
+ chain until the two files are at least at the same *depth*.
+ Then, walk up both files in synchrony until they're the same
+ file. That file is the common ancestor. */
+ int depth1 = inclusion_depth (file1);
+ int depth2 = inclusion_depth (file2);
+
+ /* Only one of these while loops will ever execute in any given
+ case. */
+ while (depth1 > depth2)
+ {
+ line1 = file1->included_at_line;
+ file1 = file1->included_by;
+ included1 = 1;
+ depth1--;
+ }
+ while (depth2 > depth1)
+ {
+ line2 = file2->included_at_line;
+ file2 = file2->included_by;
+ included2 = 1;
+ depth2--;
+ }
+
+ /* Now both file1 and file2 are at the same depth. Walk toward
+ the root of the tree until we find where the branches meet. */
+ while (file1 != file2)
+ {
+ line1 = file1->included_at_line;
+ file1 = file1->included_by;
+ /* At this point, we know that the case the includedX flags
+ are trying to deal with won't come up, but we'll just
+ maintain them anyway. */
+ included1 = 1;
+
+ line2 = file2->included_at_line;
+ file2 = file2->included_by;
+ included2 = 1;
+
+ /* Sanity check. If file1 and file2 are really from the
+ same compilation unit, then they should both be part of
+ the same tree, and this shouldn't happen. */
+ gdb_assert (file1 && file2);
+ }
+ }
+
+ /* Now we've got two line numbers in the same file. */
+ if (line1 == line2)
+ {
+ /* They can't both be from #included files. Then we shouldn't
+ have walked up this far. */
+ gdb_assert (! included1 || ! included2);
+
+ /* Any #included position comes after a non-#included position
+ with the same line number in the #including file. */
+ if (included1)
+ return 1;
+ else if (included2)
+ return -1;
+ else
+ return 0;
+ }
+ else
+ return line1 - line2;
+}
+
+
+/* Compare a macro key KEY against NAME, the source file FILE, and
+ line number LINE.
+
+ Sort definitions by name; for two definitions with the same name,
+ place the one whose definition comes earlier before the one whose
+ definition comes later.
+
+ Return -1, 0, or 1 if key comes before, is identical to, or comes
+ after NAME, FILE, and LINE. */
+static int
+key_compare (struct macro_key *key,
+ const char *name, struct macro_source_file *file, int line)
+{
+ int names = strcmp (key->name, name);
+ if (names)
+ return names;
+
+ return compare_locations (key->start_file, key->start_line,
+ file, line);
+}
+
+
+/* The macro tree comparison function, typed for the splay tree
+ library's happiness. */
+static int
+macro_tree_compare (splay_tree_key untyped_key1,
+ splay_tree_key untyped_key2)
+{
+ struct macro_key *key1 = (struct macro_key *) untyped_key1;
+ struct macro_key *key2 = (struct macro_key *) untyped_key2;
+
+ return key_compare (key1, key2->name, key2->start_file, key2->start_line);
+}
+
+
+/* Construct a new macro key node for a macro in table T whose name is
+ NAME, and whose scope starts at LINE in FILE; register the name in
+ the bcache. */
+static struct macro_key *
+new_macro_key (struct macro_table *t,
+ const char *name,
+ struct macro_source_file *file,
+ int line)
+{
+ struct macro_key *k = macro_alloc (sizeof (*k), t);
+
+ memset (k, 0, sizeof (*k));
+ k->table = t;
+ k->name = macro_bcache_str (t, name);
+ k->start_file = file;
+ k->start_line = line;
+ k->end_file = 0;
+
+ return k;
+}
+
+
+static void
+macro_tree_delete_key (void *untyped_key)
+{
+ struct macro_key *key = (struct macro_key *) untyped_key;
+
+ macro_bcache_free (key->table, (char *) key->name);
+ macro_free (key, key->table);
+}
+
+
+
+/* Building and querying the tree of #included files. */
+
+
+/* Allocate and initialize a new source file structure. */
+static struct macro_source_file *
+new_source_file (struct macro_table *t,
+ const char *filename)
+{
+ /* Get space for the source file structure itself. */
+ struct macro_source_file *f = macro_alloc (sizeof (*f), t);
+
+ memset (f, 0, sizeof (*f));
+ f->table = t;
+ f->filename = macro_bcache_str (t, filename);
+ f->includes = 0;
+
+ return f;
+}
+
+
+/* Free a source file, and all the source files it #included. */
+static void
+free_macro_source_file (struct macro_source_file *src)
+{
+ struct macro_source_file *child, *next_child;
+
+ /* Free this file's children. */
+ for (child = src->includes; child; child = next_child)
+ {
+ next_child = child->next_included;
+ free_macro_source_file (child);
+ }
+
+ macro_bcache_free (src->table, (char *) src->filename);
+ macro_free (src, src->table);
+}
+
+
+struct macro_source_file *
+macro_set_main (struct macro_table *t,
+ const char *filename)
+{
+ /* You can't change a table's main source file. What would that do
+ to the tree? */
+ gdb_assert (! t->main_source);
+
+ t->main_source = new_source_file (t, filename);
+
+ return t->main_source;
+}
+
+
+struct macro_source_file *
+macro_main (struct macro_table *t)
+{
+ gdb_assert (t->main_source);
+
+ return t->main_source;
+}
+
+
+struct macro_source_file *
+macro_include (struct macro_source_file *source,
+ int line,
+ const char *included)
+{
+ struct macro_source_file *new;
+ struct macro_source_file **link;
+
+ /* Find the right position in SOURCE's `includes' list for the new
+ file. Scan until we find the first file we shouldn't follow ---
+ which is therefore the file we should directly precede --- or
+ reach the end of the list. */
+ for (link = &source->includes;
+ *link && line < (*link)->included_at_line;
+ link = &(*link)->next_included)
+ ;
+
+ /* Did we find another file already #included at the same line as
+ the new one? */
+ if (*link && line == (*link)->included_at_line)
+ {
+ /* This means the compiler is emitting bogus debug info. (GCC
+ circa March 2002 did this.) It also means that the splay
+ tree ordering function, macro_tree_compare, will abort,
+ because it can't tell which #inclusion came first. But GDB
+ should tolerate bad debug info. So:
+
+ First, squawk. */
+ static struct complaint bogus_inclusion_line = {
+ "both `%s' and `%s' allegedly #included at %s:%d", 0, 0
+ };
+
+ complain (&bogus_inclusion_line,
+ included, (*link)->filename, source->filename, line);
+
+ /* Now, choose a new, unoccupied line number for this
+ #inclusion, after the alleged #inclusion line. */
+ while (*link && line == (*link)->included_at_line)
+ {
+ /* This line number is taken, so try the next line. */
+ line++;
+ link = &(*link)->next_included;
+ }
+ }
+
+ /* At this point, we know that LINE is an unused line number, and
+ *LINK points to the entry an #inclusion at that line should
+ precede. */
+ new = new_source_file (source->table, included);
+ new->included_by = source;
+ new->included_at_line = line;
+ new->next_included = *link;
+ *link = new;
+
+ return new;
+}
+
+
+struct macro_source_file *
+macro_lookup_inclusion (struct macro_source_file *source, const char *name)
+{
+ /* Is SOURCE itself named NAME? */
+ if (! strcmp (name, source->filename))
+ return source;
+
+ /* The filename in the source structure is probably a full path, but
+ NAME could be just the final component of the name. */
+ {
+ int name_len = strlen (name);
+ int src_name_len = strlen (source->filename);
+
+ /* We do mean < here, and not <=; if the lengths are the same,
+ then the strcmp above should have triggered, and we need to
+ check for a slash here. */
+ if (name_len < src_name_len
+ && source->filename[src_name_len - name_len - 1] == '/'
+ && ! strcmp (name, source->filename + src_name_len - name_len))
+ return source;
+ }
+
+ /* It's not us. Try all our children, and return the lowest. */
+ {
+ struct macro_source_file *child;
+ struct macro_source_file *best = 0;
+ int best_depth;
+
+ for (child = source->includes; child; child = child->next_included)
+ {
+ struct macro_source_file *result
+ = macro_lookup_inclusion (child, name);
+
+ if (result)
+ {
+ int result_depth = inclusion_depth (result);
+
+ if (! best || result_depth < best_depth)
+ {
+ best = result;
+ best_depth = result_depth;
+ }
+ }
+ }
+
+ return best;
+ }
+}
+
+
+
+/* Registering and looking up macro definitions. */
+
+
+/* Construct a definition for a macro in table T. Cache all strings,
+ and the macro_definition structure itself, in T's bcache. */
+static struct macro_definition *
+new_macro_definition (struct macro_table *t,
+ enum macro_kind kind,
+ int argc, const char **argv,
+ const char *replacement)
+{
+ struct macro_definition *d = macro_alloc (sizeof (*d), t);
+
+ memset (d, 0, sizeof (*d));
+ d->table = t;
+ d->kind = kind;
+ d->replacement = macro_bcache_str (t, replacement);
+
+ if (kind == macro_function_like)
+ {
+ int i;
+ const char **cached_argv;
+ int cached_argv_size = argc * sizeof (*cached_argv);
+
+ /* Bcache all the arguments. */
+ cached_argv = alloca (cached_argv_size);
+ for (i = 0; i < argc; i++)
+ cached_argv[i] = macro_bcache_str (t, argv[i]);
+
+ /* Now bcache the array of argument pointers itself. */
+ d->argv = macro_bcache (t, cached_argv, cached_argv_size);
+ d->argc = argc;
+ }
+
+ /* We don't bcache the entire definition structure because it's got
+ a pointer to the macro table in it; since each compilation unit
+ has its own macro table, you'd only get bcache hits for identical
+ definitions within a compilation unit, which seems unlikely.
+
+ "So, why do macro definitions have pointers to their macro tables
+ at all?" Well, when the splay tree library wants to free a
+ node's value, it calls the value freeing function with nothing
+ but the value itself. It makes the (apparently reasonable)
+ assumption that the value carries enough information to free
+ itself. But not all macro tables have bcaches, so not all macro
+ definitions would be bcached. There's no way to tell whether a
+ given definition is bcached without knowing which table the
+ definition belongs to. ... blah. The thing's only sixteen
+ bytes anyway, and we can still bcache the name, args, and
+ definition, so we just don't bother bcaching the definition
+ structure itself. */
+ return d;
+}
+
+
+/* Free a macro definition. */
+static void
+macro_tree_delete_value (void *untyped_definition)
+{
+ struct macro_definition *d = (struct macro_definition *) untyped_definition;
+ struct macro_table *t = d->table;
+
+ if (d->kind == macro_function_like)
+ {
+ int i;
+
+ for (i = 0; i < d->argc; i++)
+ macro_bcache_free (t, (char *) d->argv[i]);
+ macro_bcache_free (t, (char **) d->argv);
+ }
+
+ macro_bcache_free (t, (char *) d->replacement);
+ macro_free (d, t);
+}
+
+
+/* Find the splay tree node for the definition of NAME at LINE in
+ SOURCE, or zero if there is none. */
+static splay_tree_node
+find_definition (const char *name,
+ struct macro_source_file *file,
+ int line)
+{
+ struct macro_table *t = file->table;
+ splay_tree_node n;
+
+ /* Construct a macro_key object, just for the query. */
+ struct macro_key query;
+
+ query.name = name;
+ query.start_file = file;
+ query.start_line = line;
+ query.end_file = 0;
+
+ n = splay_tree_lookup (t->definitions, (splay_tree_key) &query);
+ if (! n)
+ {
+ /* It's okay for us to do two queries like this: the real work
+ of the searching is done when we splay, and splaying the tree
+ a second time at the same key is a constant time operation.
+ If this still bugs you, you could always just extend the
+ splay tree library with a predecessor-or-equal operation, and
+ use that. */
+ splay_tree_node pred = splay_tree_predecessor (t->definitions,
+ (splay_tree_key) &query);
+
+ if (pred)
+ {
+ /* Make sure this predecessor actually has the right name.
+ We just want to search within a given name's definitions. */
+ struct macro_key *found = (struct macro_key *) pred->key;
+
+ if (! strcmp (found->name, name))
+ n = pred;
+ }
+ }
+
+ if (n)
+ {
+ struct macro_key *found = (struct macro_key *) n->key;
+
+ /* Okay, so this definition has the right name, and its scope
+ begins before the given source location. But does its scope
+ end after the given source location? */
+ if (compare_locations (file, line, found->end_file, found->end_line) < 0)
+ return n;
+ else
+ return 0;
+ }
+ else
+ return 0;
+}
+
+
+/* If NAME already has a definition in scope at LINE in FILE, and
+ return the key. Otherwise, return zero. */
+static struct macro_key *
+check_for_redefinition (struct macro_source_file *source, int line,
+ const char *name)
+{
+ splay_tree_node n = find_definition (name, source, line);
+
+ /* This isn't really right. There's nothing wrong with redefining a
+ macro if the new replacement list is the same as the old one. */
+ if (n)
+ {
+ struct macro_key *found_key = (struct macro_key *) n->key;
+ static struct complaint macro_redefined = {
+ "macro `%s' redefined at %s:%d;"
+ "original definition at %s:%d", 0, 0
+ };
+ complain (&macro_redefined, name,
+ source->filename, line,
+ found_key->start_file->filename,
+ found_key->start_line);
+ return found_key;
+ }
+ else
+ return 0;
+}
+
+
+void
+macro_define_object (struct macro_source_file *source, int line,
+ const char *name, const char *replacement)
+{
+ struct macro_table *t = source->table;
+ struct macro_key *k;
+ struct macro_definition *d;
+
+ k = check_for_redefinition (source, line, name);
+
+ /* If we're redefining a symbol, and the existing key would be
+ identical to our new key, then the splay_tree_insert function
+ will try to delete the old definition. When the definition is
+ living on an obstack, this isn't a happy thing.
+
+ Since this only happens in the presence of questionable debug
+ info, we just ignore all definitions after the first. The only
+ case I know of where this arises is in GCC's output for
+ predefined macros, and all the definitions are the same in that
+ case. */
+ if (k && ! key_compare (k, name, source, line))
+ return;
+
+ k = new_macro_key (t, name, source, line);
+ d = new_macro_definition (t, macro_object_like, 0, 0, replacement);
+ splay_tree_insert (t->definitions, (splay_tree_key) k, (splay_tree_value) d);
+}
+
+
+void
+macro_define_function (struct macro_source_file *source, int line,
+ const char *name, int argc, const char **argv,
+ const char *replacement)
+{
+ struct macro_table *t = source->table;
+ struct macro_key *k;
+ struct macro_definition *d;
+
+ k = check_for_redefinition (source, line, name);
+
+ /* See comments about duplicate keys in macro_define_object. */
+ if (k && ! key_compare (k, name, source, line))
+ return;
+
+ /* We should also check here that all the argument names in ARGV are
+ distinct. */
+
+ k = new_macro_key (t, name, source, line);
+ d = new_macro_definition (t, macro_function_like, argc, argv, replacement);
+ splay_tree_insert (t->definitions, (splay_tree_key) k, (splay_tree_value) d);
+}
+
+
+void
+macro_undef (struct macro_source_file *source, int line,
+ const char *name)
+{
+ splay_tree_node n = find_definition (name, source, line);
+
+ if (n)
+ {
+ /* This function is the only place a macro's end-of-scope
+ location gets set to anything other than "end of the
+ compilation unit" (i.e., end_file is zero). So if this macro
+ already has its end-of-scope set, then we're probably seeing
+ a second #undefinition for the same #definition. */
+ struct macro_key *key = (struct macro_key *) n->key;
+
+ if (key->end_file)
+ {
+ static struct complaint double_undef = {
+ "macro '%s' is #undefined twice, at %s:%d and %s:%d",
+ 0, 0
+ };
+ complain (&double_undef, name, source->filename, line,
+ key->end_file->filename, key->end_line);
+ }
+
+ /* Whatever the case, wipe out the old ending point, and
+ make this the ending point. */
+ key->end_file = source;
+ key->end_line = line;
+ }
+ else
+ {
+ /* According to the ISO C standard, an #undef for a symbol that
+ has no macro definition in scope is ignored. So we should
+ ignore it too. */
+#if 0
+ static struct complaint no_macro_to_undefine = {
+ "no definition for macro `%s' in scope to #undef at %s:%d",
+ 0, 0
+ };
+ complain (&no_macro_to_undefine, name, source->filename, line);
+#endif
+ }
+}
+
+
+struct macro_definition *
+macro_lookup_definition (struct macro_source_file *source,
+ int line, const char *name)
+{
+ splay_tree_node n = find_definition (name, source, line);
+
+ if (n)
+ return (struct macro_definition *) n->value;
+ else
+ return 0;
+}
+
+
+struct macro_source_file *
+macro_definition_location (struct macro_source_file *source,
+ int line,
+ const char *name,
+ int *definition_line)
+{
+ splay_tree_node n = find_definition (name, source, line);
+
+ if (n)
+ {
+ struct macro_key *key = (struct macro_key *) n->key;
+ *definition_line = key->start_line;
+ return key->start_file;
+ }
+ else
+ return 0;
+}
+
+
+
+/* Creating and freeing macro tables. */
+
+
+struct macro_table *
+new_macro_table (struct obstack *obstack,
+ struct bcache *b)
+{
+ struct macro_table *t;
+
+ /* First, get storage for the `struct macro_table' itself. */
+ if (obstack)
+ t = obstack_alloc (obstack, sizeof (*t));
+ else
+ t = xmalloc (sizeof (*t));
+
+ memset (t, 0, sizeof (*t));
+ t->obstack = obstack;
+ t->bcache = b;
+ t->main_source = 0;
+ t->definitions = (splay_tree_new_with_allocator
+ (macro_tree_compare,
+ ((splay_tree_delete_key_fn) macro_tree_delete_key),
+ ((splay_tree_delete_value_fn) macro_tree_delete_value),
+ ((splay_tree_allocate_fn) macro_alloc),
+ ((splay_tree_deallocate_fn) macro_free),
+ t));
+
+ return t;
+}
+
+
+void
+free_macro_table (struct macro_table *table)
+{
+ /* Free the source file tree. */
+ free_macro_source_file (table->main_source);
+
+ /* Free the table of macro definitions. */
+ splay_tree_delete (table->definitions);
+}