FYI: index pre-expansion fix
http://sourceware.org/ml/gdb-patches/2010-09/msg00452.html
http://sourceware.org/ml/gdb-cvs/2010-09/msg00165.html
### src/gdb/ChangeLog 2010/09/27 17:41:35 1.12206
### src/gdb/ChangeLog 2010/09/27 18:42:35 1.12207
## -1,5 +1,17 @@
2010-09-27 Tom Tromey <tromey@redhat.com>
+ * dwarf2read.c (dwarf2_read_index): Only allow version 3.
+ (write_psymbols): Add 'psyms_seen' and 'is_static' arguments.
+ Only emit a given psymbol once.
+ (struct signatured_type_index_data) <psyms_seen>: New field.
+ (write_one_signatured_type): Update.
+ (cleanup_htab): New function.
+ (write_psymtabs_to_index): Update. Create psyms_seen hash. Bump
+ version to 3.
+ (save_gdb_index_command): Update index documentation.
+
+2010-09-27 Tom Tromey <tromey@redhat.com>
+
* bcache.c (expand_hash_table): Use hash_function, not hash.
2010-09-27 Tom Tromey <tromey@redhat.com>
Index: gdb-7.2/gdb/dwarf2read.c
===================================================================
--- gdb-7.2.orig/gdb/dwarf2read.c 2010-10-12 18:11:27.000000000 +0200
+++ gdb-7.2/gdb/dwarf2read.c 2010-10-12 18:12:03.000000000 +0200
@@ -1897,15 +1897,10 @@ dwarf2_read_index (struct objfile *objfi
addr = dwarf2_per_objfile->gdb_index.buffer;
/* Version check. */
version = MAYBE_SWAP (*(offset_type *) addr);
- if (version == 1)
- {
- /* Index version 1 neglected to account for .debug_types. So,
- if we see .debug_types, we cannot use this index. */
- if (dwarf2_per_objfile->types.asection != NULL
- && dwarf2_per_objfile->types.size != 0)
- return 0;
- }
- else if (version != 2)
+ /* Versions earlier than 3 emitted every copy of a psymbol. This
+ causes the index to behave very poorly for certain requests. So,
+ it seems better to just ignore such indices. */
+ if (version < 3)
return 0;
map = OBSTACK_ZALLOC (&objfile->objfile_obstack, struct mapped_index);
@@ -1919,14 +1914,11 @@ dwarf2_read_index (struct objfile *objfi
/ 8);
++i;
- if (version == 2)
- {
- types_list = addr + MAYBE_SWAP (metadata[i]);
- types_list_elements = ((MAYBE_SWAP (metadata[i + 1])
- - MAYBE_SWAP (metadata[i]))
- / 8);
- ++i;
- }
+ types_list = addr + MAYBE_SWAP (metadata[i]);
+ types_list_elements = ((MAYBE_SWAP (metadata[i + 1])
+ - MAYBE_SWAP (metadata[i]))
+ / 8);
+ ++i;
map->address_table = addr + MAYBE_SWAP (metadata[i]);
map->address_table_size = (MAYBE_SWAP (metadata[i + 1])
@@ -1944,8 +1936,7 @@ dwarf2_read_index (struct objfile *objfi
if (!create_cus_from_index (objfile, cu_list, cu_list_elements))
return 0;
- if (version == 2
- && types_list_elements
+ if (types_list_elements
&& !create_signatured_type_hash_from_index (objfile, types_list,
types_list_elements))
return 0;
@@ -14568,15 +14559,38 @@ add_address_entry (struct objfile *objfi
/* Add a list of partial symbols to SYMTAB. */
static void
write_psymbols (struct mapped_symtab *symtab,
+ htab_t psyms_seen,
struct partial_symbol **psymp,
int count,
- offset_type cu_index)
+ offset_type cu_index,
+ int is_static)
{
for (; count-- > 0; ++psymp)
{
+ void **slot, *lookup;
+
if (SYMBOL_LANGUAGE (*psymp) == language_ada)
error (_("Ada is not currently supported by the index"));
- add_index_entry (symtab, SYMBOL_NATURAL_NAME (*psymp), cu_index);
+
+ /* We only want to add a given psymbol once. However, we also
+ want to account for whether it is global or static. So, we
+ may add it twice, using slightly different values. */
+ if (is_static)
+ {
+ uintptr_t val = 1 | (uintptr_t) *psymp;
+
+ lookup = (void *) val;
+ }
+ else
+ lookup = *psymp;
+
+ /* Only add a given psymbol once. */
+ slot = htab_find_slot (psyms_seen, lookup, INSERT);
+ if (!*slot)
+ {
+ *slot = lookup;
+ add_index_entry (symtab, SYMBOL_NATURAL_NAME (*psymp), cu_index);
+ }
}
}
@@ -14606,6 +14620,7 @@ struct signatured_type_index_data
struct objfile *objfile;
struct mapped_symtab *symtab;
struct obstack *types_list;
+ htab_t psyms_seen;
int cu_index;
};
@@ -14621,11 +14636,15 @@ write_one_signatured_type (void **slot,
gdb_byte val[8];
write_psymbols (info->symtab,
+ info->psyms_seen,
info->objfile->global_psymbols.list + psymtab->globals_offset,
- psymtab->n_global_syms, info->cu_index);
+ psymtab->n_global_syms, info->cu_index,
+ 0);
write_psymbols (info->symtab,
+ info->psyms_seen,
info->objfile->static_psymbols.list + psymtab->statics_offset,
- psymtab->n_static_syms, info->cu_index);
+ psymtab->n_static_syms, info->cu_index,
+ 1);
store_unsigned_integer (val, 8, BFD_ENDIAN_LITTLE, entry->offset);
obstack_grow (info->types_list, val, 8);
@@ -14639,6 +14658,14 @@ write_one_signatured_type (void **slot,
return 1;
}
+/* A cleanup function for an htab_t. */
+
+static void
+cleanup_htab (void *arg)
+{
+ htab_delete (arg);
+}
+
/* Create an index file for OBJFILE in the directory DIR. */
static void
write_psymtabs_to_index (struct objfile *objfile, const char *dir)
@@ -14653,6 +14680,7 @@ write_psymtabs_to_index (struct objfile
offset_type val, size_of_contents, total_len;
struct stat st;
char buf[8];
+ htab_t psyms_seen;
if (!objfile->psymtabs)
return;
@@ -14685,6 +14713,10 @@ write_psymtabs_to_index (struct objfile
obstack_init (&types_cu_list);
make_cleanup_obstack_free (&types_cu_list);
+ psyms_seen = htab_create_alloc (100, htab_hash_pointer, htab_eq_pointer,
+ NULL, xcalloc, xfree);
+ make_cleanup (cleanup_htab, psyms_seen);
+
/* The list is already sorted, so we don't need to do additional
work here. Also, the debug_types entries do not appear in
all_comp_units, but only in their own hash table. */
@@ -14695,11 +14727,15 @@ write_psymtabs_to_index (struct objfile
gdb_byte val[8];
write_psymbols (symtab,
+ psyms_seen,
objfile->global_psymbols.list + psymtab->globals_offset,
- psymtab->n_global_syms, i);
+ psymtab->n_global_syms, i,
+ 0);
write_psymbols (symtab,
+ psyms_seen,
objfile->static_psymbols.list + psymtab->statics_offset,
- psymtab->n_static_syms, i);
+ psymtab->n_static_syms, i,
+ 1);
add_address_entry (objfile, &addr_obstack, psymtab, i);
@@ -14717,6 +14753,7 @@ write_psymtabs_to_index (struct objfile
sig_data.objfile = objfile;
sig_data.symtab = symtab;
sig_data.types_list = &types_cu_list;
+ sig_data.psyms_seen = psyms_seen;
sig_data.cu_index = dwarf2_per_objfile->n_comp_units;
htab_traverse_noresize (dwarf2_per_objfile->signatured_types,
write_one_signatured_type, &sig_data);
@@ -14734,7 +14771,7 @@ write_psymtabs_to_index (struct objfile
total_len = size_of_contents;
/* The version number. */
- val = MAYBE_SWAP (2);
+ val = MAYBE_SWAP (3);
obstack_grow (&contents, &val, sizeof (val));
/* The offset of the CU list from the start of the file. */
@@ -14791,18 +14828,16 @@ write_psymtabs_to_index (struct objfile
1. The file header. This is a sequence of values, of offset_type
unless otherwise noted:
- [0] The version number. Currently 1 or 2. The differences are
- noted below. Version 1 did not account for .debug_types sections;
- the presence of a .debug_types section invalidates any version 1
- index that may exist.
+
+ [0] The version number, currently 3. Versions 1 and 2 are
+ obsolete.
[1] The offset, from the start of the file, of the CU list.
- [1.5] In version 2, the offset, from the start of the file, of the
- types CU list. This offset does not appear in version 1. Note
- that this can be empty, in which case this offset will be equal to
- the next offset.
- [2] The offset, from the start of the file, of the address section.
- [3] The offset, from the start of the file, of the symbol table.
- [4] The offset, from the start of the file, of the constant pool.
+ [2] The offset, from the start of the file, of the types CU list.
+ Note that this section can be empty, in which case this offset will
+ be equal to the next offset.
+ [3] The offset, from the start of the file, of the address section.
+ [4] The offset, from the start of the file, of the symbol table.
+ [5] The offset, from the start of the file, of the constant pool.
2. The CU list. This is a sequence of pairs of 64-bit
little-endian values, sorted by the CU offset. The first element
@@ -14813,19 +14848,19 @@ write_psymtabs_to_index (struct objfile
type CUs, then conceptually CUs and type CUs form a single list for
the purposes of CU indices.
- 2.5 The types CU list. This does not appear in a version 1 index.
- This is a sequence of triplets of 64-bit little-endian values. In
- a triplet, the first value is the CU offset, the second value is
- the type offset in the CU, and the third value is the type
- signature. The types CU list is not sorted.
+ 3. The types CU list. This is a sequence of triplets of 64-bit
+ little-endian values. In a triplet, the first value is the CU
+ offset, the second value is the type offset in the CU, and the
+ third value is the type signature. The types CU list is not
+ sorted.
- 3. The address section. The address section consists of a sequence
+ 4. The address section. The address section consists of a sequence
of address entries. Each address entry has three elements.
[0] The low address. This is a 64-bit little-endian value.
[1] The high address. This is a 64-bit little-endian value.
[2] The CU index. This is an offset_type value.
- 4. The symbol table. This is a hash table. The size of the hash
+ 5. The symbol table. This is a hash table. The size of the hash
table is always a power of 2. The initial hash and the step are
currently defined by the `find_slot' function.
@@ -14847,7 +14882,7 @@ write_psymtabs_to_index (struct objfile
element in the hash table is used to indicate which CUs define the
symbol.
- 5. The constant pool. This is simply a bunch of bytes. It is
+ 6. The constant pool. This is simply a bunch of bytes. It is
organized so that alignment is correct: CU vectors are stored
first, followed by strings. */
static void