From 8cf3a675c44dcccd54f64db47b7baea637c250ea Mon Sep 17 00:00:00 2001
From: Pierre-Marie de Rodat <derodat@adacore.com>
Date: Thu, 5 Feb 2015 17:00:06 +0100
Subject: [PATCH] DWARF: handle non-local references in nested functions
GDB's current behavior when dealing with non-local references in the
context of nested fuctions is approximative:
- code using valops.c:value_of_variable read the first available stack
frame that holds the corresponding variable (whereas there can be
multiple candidates for this);
- code directly relying on read_var_value will instead read non-local
variables in frames where they are not even defined.
This change adds the necessary context to symbol reads (to get the block
they belong to) and to blocks (the static link property, if any) so that
GDB can make the proper decisions when dealing with non-local varibale
references.
gdb/ChangeLog:
* ada-lang.c (ada_read_var_value): Add a VAR_BLOCK argument and pass
it to default_read_var_value.
* block.c (block_static_link): New accessor.
* block.h (block_static_link): Declare it.
* buildsym.c (finish_block_internal): Add a static_link
argument. If there is a static link, associate it to the new
block.
(finish_block): Add a static link argument and pass it to
finish_block_internal.
(end_symtab_get_static_block): Update calls to finish_block and
to finish_block_internal.
(end_symtab_with_blockvector): Update call to
finish_block_internal.
* buildsym.h: Forward-declare struct dynamic_prop.
(struct context_stack): Add a static_link field.
(finish_block): Add a static link argument.
* coffread.c (coff_symtab_read): Update calls to finish_block.
* dbxread.c (process_one_symbol): Likewise.
* xcoffread.c (read_xcoff_symtab): Likewise.
* compile/compile-c-symbols.c (convert_one_symbol): Add a
VAR_BLOCK parameter and pass it to calls to read_var_value.
(convert_symbol_sym): Pass the block corresponding to SYM to the
call to convert_one_symbol.
* compile/compile-loc2c.c (do_compile_dwarf_expr_to_c): Update
call to read_var_value.
* dwarf2loc.c (block_op_get_frame_base): New.
(dwarf2_block_frame_base_locexpr_funcs): Implement the
get_frame_base method.
(dwarf2_block_frame_base_loclist_funcs): Likewise.
(dwarf2locexpr_baton_eval): Add a frame argument and use it
instead of the selected frame in order to evaluate the
expression.
(dwarf2_evaluate_property): Add a frame argument. Update call
to dwarf2_locexpr_baton_eval to provide a frame in available and
to handle the absence of address stack.
* dwarf2loc.h (dwarf2_evaluate_property): Add a frame argument.
* dwarf2read.c (attr_to_dynamic_prop): Add a forward
declaration.
(read_func_scope): Record any available static link description.
Update call to finish_block.
(read_lexical_block_scope): Update call to finish_block.
* findvar.c (follow_static_link): New.
(get_hosting_frame): New.
(default_read_var_value): Add a VAR_BLOCK argument. Use
get_hosting_frame to handle non-local references.
(read_var_value): Add a VAR_BLOCK argument and pass it to the
LA_READ_VAR_VALUE method.
* gdbtypes.c (resolve_dynamic_range): Update calls to
dwarf2_evaluate_property.
(resolve_dynamic_type_internal): Likewise.
* infcmd.c (finish_command_continuation): Update call to
read_var_value, passing it the block coming from symbol lookup.
* infrun.c (insert_exception_resume_breakpoint): Likewise.
* language.h (struct language_defn): Add a VAR_BLOCK argument to
the LA_READ_VAR_VALUE method.
* objfiles.c (objfile_register_static_link): New.
(objfile_lookup_static_link): New.
(free_objfile): Free the STATIC_LINKS hashed map if needed.
* objfiles.h: Include hashtab.h.
(struct objfile): Add a STATIC_LINKS field.
(objfile_register_static_link): New.
(objfile_lookup_static_link): New.
* printcmd.c (print_variable_and_value): Update call to
read_var_value.
* python/py-finishbreakpoint.c (bpfinishpy_init): Likewise.
* python/py-frame.c (frapy_read_var): Update call to
read_var_value, passing it the block coming from symbol lookup.
* python/py-framefilter.c (extract_sym): Add a SYM_BLOCK
parameter and set the pointed value to NULL (TODO).
(enumerate_args): Update call to extract_sym.
(enumerate_locals): Update calls to extract_sym and to
read_var_value.
* python/py-symbol.c (sympy_value): Update call to
read_var_value (TODO).
* stack.c (read_frame_local): Update call to read_var_value.
(read_frame_arg): Likewise.
(return_command): Likewise.
* symtab.h (struct symbol_block_ops): Add a get_frame_base
method.
(struct symbol): Add a block field.
(SYMBOL_BLOCK): New accessor.
* valops.c (value_of_variable): Remove frame/block handling and
pass the block argument to read_var_value, which does this job
now.
(value_struct_elt_for_reference): Update calls to
read_var_value.
(value_of_this): Pass the block found to read_var_value.
* value.h (read_var_value): Add a VAR_BLOCK argument.
(default_read_var_value): Likewise.
gdb/testsuite/ChangeLog:
* gdb.base/nested-subp1.exp: New file.
* gdb.base/nested-subp1.c: New file.
* gdb.base/nested-subp2.exp: New file.
* gdb.base/nested-subp2.c: New file.
* gdb.base/nested-subp3.exp: New file.
* gdb.base/nested-subp3.c: New file.
---
gdb/ada-lang.c | 5 +-
gdb/block.c | 15 +++
gdb/block.h | 6 ++
gdb/buildsym.c | 17 ++--
gdb/buildsym.h | 14 ++-
gdb/coffread.c | 4 +-
gdb/compile/compile-c-symbols.c | 19 ++--
gdb/compile/compile-loc2c.c | 2 +-
gdb/dbxread.c | 8 +-
gdb/dwarf2loc.c | 52 ++++++++--
gdb/dwarf2loc.h | 11 ++-
gdb/dwarf2read.c | 19 +++-
gdb/findvar.c | 168 +++++++++++++++++++++++++++++++-
gdb/gdbtypes.c | 7 +-
gdb/infcmd.c | 2 +-
gdb/infrun.c | 7 +-
gdb/language.h | 12 ++-
gdb/objfiles.c | 36 +++++++
gdb/objfiles.h | 18 ++++
gdb/printcmd.c | 6 +-
gdb/python/py-finishbreakpoint.c | 2 +-
gdb/python/py-frame.c | 9 +-
gdb/python/py-framefilter.c | 28 ++++--
gdb/python/py-symbol.c | 5 +-
gdb/stack.c | 8 +-
gdb/symtab.h | 18 ++++
gdb/testsuite/gdb.base/nested-subp1.c | 37 +++++++
gdb/testsuite/gdb.base/nested-subp1.exp | 55 +++++++++++
gdb/testsuite/gdb.base/nested-subp2.c | 48 +++++++++
gdb/testsuite/gdb.base/nested-subp2.exp | 64 ++++++++++++
gdb/testsuite/gdb.base/nested-subp3.c | 66 +++++++++++++
gdb/testsuite/gdb.base/nested-subp3.exp | 55 +++++++++++
gdb/valops.c | 35 ++-----
gdb/value.h | 2 +
gdb/xcoffread.c | 4 +-
35 files changed, 763 insertions(+), 101 deletions(-)
create mode 100644 gdb/testsuite/gdb.base/nested-subp1.c
create mode 100644 gdb/testsuite/gdb.base/nested-subp1.exp
create mode 100644 gdb/testsuite/gdb.base/nested-subp2.c
create mode 100644 gdb/testsuite/gdb.base/nested-subp2.exp
create mode 100644 gdb/testsuite/gdb.base/nested-subp3.c
create mode 100644 gdb/testsuite/gdb.base/nested-subp3.exp
@@ -13750,7 +13750,8 @@ ada_get_symbol_name_cmp (const char *lookup_name)
/* Implement the "la_read_var_value" language_defn method for Ada. */
static struct value *
-ada_read_var_value (struct symbol *var, struct frame_info *frame)
+ada_read_var_value (struct symbol *var, const struct block *var_block,
+ struct frame_info *frame)
{
const struct block *frame_block = NULL;
struct symbol *renaming_sym = NULL;
@@ -13766,7 +13767,7 @@ ada_read_var_value (struct symbol *var, struct frame_info *frame)
/* This is a typical case where we expect the default_read_var_value
function to work. */
- return default_read_var_value (var, frame);
+ return default_read_var_value (var, var_block, frame);
}
const struct language_defn ada_language_defn = {
@@ -428,6 +428,21 @@ set_block_compunit_symtab (struct block *block, struct compunit_symtab *cu)
gb->compunit_symtab = cu;
}
+/* See block.h. */
+
+struct dynamic_prop *
+block_static_link (const struct block *block)
+{
+ struct objfile *objfile = block_objfile (block);
+
+ /* Only objfile-owned blocks that materialize top function scopes can have
+ static links. */
+ if (objfile == NULL || BLOCK_FUNCTION (block) == NULL)
+ return NULL;
+
+ return (struct dynamic_prop *) objfile_lookup_static_link (objfile, block);
+}
+
/* Return the compunit of the global block. */
static struct compunit_symtab *
@@ -190,6 +190,12 @@ extern struct block *allocate_global_block (struct obstack *obstack);
extern void set_block_compunit_symtab (struct block *,
struct compunit_symtab *);
+/* Return a property to evaluate the static link associated to BLOCK. Note
+ that only objfile-owned and function-level blocks can have a static link.
+ Return NULL if there is no such property. */
+
+extern struct dynamic_prop *block_static_link (const struct block *block);
+
/* A block iterator. This structure should be treated as though it
were opaque; it is only defined here because we want to support
stack allocation of iterators. */
@@ -331,7 +331,8 @@ free_pending_blocks (void)
file). Put the block on the list of pending blocks. */
static struct block *
-finish_block_internal (struct symbol *symbol, struct pending **listhead,
+finish_block_internal (struct symbol *symbol, struct dynamic_prop *static_link,
+ struct pending **listhead,
struct pending_block *old_blocks,
CORE_ADDR start, CORE_ADDR end,
int is_global, int expandable)
@@ -422,6 +423,9 @@ finish_block_internal (struct symbol *symbol, struct pending **listhead,
BLOCK_FUNCTION (block) = NULL;
}
+ if (static_link != NULL)
+ objfile_register_static_link (objfile, block, static_link);
+
/* Now "free" the links of the list, and empty the list. */
for (next = *listhead; next; next = next1)
@@ -512,11 +516,12 @@ finish_block_internal (struct symbol *symbol, struct pending **listhead,
}
struct block *
-finish_block (struct symbol *symbol, struct pending **listhead,
+finish_block (struct symbol *symbol, struct dynamic_prop *static_link,
+ struct pending **listhead,
struct pending_block *old_blocks,
CORE_ADDR start, CORE_ADDR end)
{
- return finish_block_internal (symbol, listhead, old_blocks,
+ return finish_block_internal (symbol, static_link, listhead, old_blocks,
start, end, 0, 0);
}
@@ -1218,7 +1223,7 @@ end_symtab_get_static_block (CORE_ADDR end_addr, int expandable, int required)
struct context_stack *cstk = pop_context ();
/* Make a block for the local symbols within. */
- finish_block (cstk->name, &local_symbols, cstk->old_blocks,
+ finish_block (cstk->name, NULL, &local_symbols, cstk->old_blocks,
cstk->start_addr, end_addr);
if (context_stack_depth > 0)
@@ -1289,7 +1294,7 @@ end_symtab_get_static_block (CORE_ADDR end_addr, int expandable, int required)
else
{
/* Define the STATIC_BLOCK. */
- return finish_block_internal (NULL, &file_symbols, NULL,
+ return finish_block_internal (NULL, NULL, &file_symbols, NULL,
last_source_start_addr, end_addr,
0, expandable);
}
@@ -1317,7 +1322,7 @@ end_symtab_with_blockvector (struct block *static_block,
end_addr = BLOCK_END (static_block);
/* Create the GLOBAL_BLOCK and build the blockvector. */
- finish_block_internal (NULL, &global_symbols, NULL,
+ finish_block_internal (NULL, NULL, &global_symbols, NULL,
last_source_start_addr, end_addr,
1, expandable);
blockvector = make_blockvector ();
@@ -39,6 +39,8 @@ struct compunit_symtab;
struct block;
struct pending_block;
+struct dynamic_prop;
+
#ifndef EXTERN
#define EXTERN extern
#endif
@@ -141,6 +143,11 @@ struct context_stack
struct symbol *name;
+ /* Expression that computes the frame base of the lexically enclosing
+ function, if any. NULL otherwise. */
+
+ struct dynamic_prop *static_link;
+
/* PC where this context starts */
CORE_ADDR start_addr;
@@ -192,9 +199,10 @@ extern struct symbol *find_symbol_in_list (struct pending *list,
char *name, int length);
extern struct block *finish_block (struct symbol *symbol,
- struct pending **listhead,
- struct pending_block *old_blocks,
- CORE_ADDR start, CORE_ADDR end);
+ struct dynamic_prop *static_link,
+ struct pending **listhead, struct
+ pending_block *old_blocks, CORE_ADDR start,
+ CORE_ADDR end);
extern void record_block_range (struct block *,
CORE_ADDR start, CORE_ADDR end_inclusive);
@@ -1144,7 +1144,7 @@ coff_symtab_read (long symtab_offset, unsigned int nsyms,
enter_linenos (fcn_line_ptr, fcn_first_line,
fcn_last_line, objfile);
- finish_block (newobj->name, &local_symbols,
+ finish_block (newobj->name, NULL, &local_symbols,
newobj->old_blocks, newobj->start_addr,
fcn_cs_saved.c_value
+ fcn_aux_saved.x_sym.x_misc.x_fsize
@@ -1188,7 +1188,7 @@ coff_symtab_read (long symtab_offset, unsigned int nsyms,
cs->c_value + ANOFFSET (objfile->section_offsets,
SECT_OFF_TEXT (objfile));
/* Make a block for the local symbols within. */
- finish_block (0, &local_symbols, newobj->old_blocks,
+ finish_block (0, NULL, &local_symbols, newobj->old_blocks,
newobj->start_addr, tmpaddr);
}
/* Now pop locals of block just finished. */
@@ -134,16 +134,16 @@ symbol_substitution_name (struct symbol *sym)
return concat ("__", SYMBOL_NATURAL_NAME (sym), "_ptr", (char *) NULL);
}
-/* Convert a given symbol, SYM, to the compiler's representation.
- CONTEXT is the compiler instance. IS_GLOBAL is true if the
- symbol came from the global scope. IS_LOCAL is true if the symbol
- came from a local scope. (Note that the two are not strictly
- inverses because the symbol might have come from the static
- scope.) */
+/* Convert a given symbol, SYM (located in VAR_BLOCK, if any), to the
+ compiler's representation. CONTEXT is the compiler instance. IS_GLOBAL is
+ true if the symbol came from the global scope. IS_LOCAL is true if the
+ symbol came from a local scope. (Note that the two are not strictly
+ inverses because the symbol might have come from the static scope.) */
static void
convert_one_symbol (struct compile_c_instance *context,
struct symbol *sym,
+ const struct block *var_block,
int is_global,
int is_local)
{
@@ -247,7 +247,7 @@ convert_one_symbol (struct compile_c_instance *context,
SYMBOL_PRINT_NAME (sym));
}
- val = read_var_value (sym, frame);
+ val = read_var_value (sym, var_block, frame);
if (VALUE_LVAL (val) != lval_memory)
error (_("Symbol \"%s\" cannot be used for compilation "
"evaluation as its address has not been found."),
@@ -339,7 +339,8 @@ convert_symbol_sym (struct compile_c_instance *context, const char *identifier,
fprintf_unfiltered (gdb_stdlog,
"gcc_convert_symbol \"%s\": global symbol\n",
identifier);
- convert_one_symbol (context, global_sym.symbol, 1, 0);
+ convert_one_symbol (context, global_sym.symbol, global_sym.block, 1,
+ 0);
}
}
@@ -347,7 +348,7 @@ convert_symbol_sym (struct compile_c_instance *context, const char *identifier,
fprintf_unfiltered (gdb_stdlog,
"gcc_convert_symbol \"%s\": local symbol\n",
identifier);
- convert_one_symbol (context, sym, 0, is_local_symbol);
+ convert_one_symbol (context, sym, block, 0, is_local_symbol);
}
/* Convert a minimal symbol to its gcc form. CONTEXT is the compiler
@@ -636,7 +636,7 @@ do_compile_dwarf_expr_to_c (int indent, struct ui_file *stream,
"there is no selected frame"),
SYMBOL_PRINT_NAME (sym));
- val = read_var_value (sym, frame);
+ val = read_var_value (sym, NULL, frame);
if (VALUE_LVAL (val) != lval_memory)
error (_("Symbol \"%s\" cannot be used for compilation evaluation "
"as its address has not been found."),
@@ -2766,8 +2766,8 @@ process_one_symbol (int type, int desc, CORE_ADDR valu, char *name,
newobj = pop_context ();
/* Make a block for the local symbols within. */
- block = finish_block (newobj->name, &local_symbols,
- newobj->old_blocks,
+ block = finish_block (newobj->name, NULL,
+ &local_symbols, newobj->old_blocks,
newobj->start_addr, newobj->start_addr + valu);
/* For C++, set the block's scope. */
@@ -2868,7 +2868,7 @@ process_one_symbol (int type, int desc, CORE_ADDR valu, char *name,
newobj->start_addr = valu;
}
/* Make a block for the local symbols within. */
- finish_block (0, &local_symbols, newobj->old_blocks,
+ finish_block (0, NULL, &local_symbols, newobj->old_blocks,
newobj->start_addr, valu);
}
}
@@ -3165,7 +3165,7 @@ process_one_symbol (int type, int desc, CORE_ADDR valu, char *name,
newobj = pop_context ();
/* Make a block for the local symbols within. */
- block = finish_block (newobj->name, &local_symbols,
+ block = finish_block (newobj->name, NULL, &local_symbols,
newobj->old_blocks, newobj->start_addr,
valu);
@@ -381,12 +381,42 @@ locexpr_find_frame_base_location (struct symbol *framefunc, CORE_ADDR pc,
*start = symbaton->data;
}
+/* Implement the struct symbol_block_ops::get_frame_base method. */
+
+static CORE_ADDR
+block_op_get_frame_base (struct symbol *framefunc, struct frame_info *frame)
+{
+ if (SYMBOL_BLOCK_OPS (framefunc)->find_frame_base_location != NULL)
+ {
+ struct gdbarch *gdbarch = get_frame_arch (frame);
+ struct type *type = builtin_type (gdbarch)->builtin_data_ptr;
+ struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (framefunc);
+ const gdb_byte *start;
+ size_t length;
+ struct value *result;
+
+ SYMBOL_BLOCK_OPS (framefunc)->find_frame_base_location
+ (framefunc, get_frame_pc (frame), &start, &length);
+ result = dwarf2_evaluate_loc_desc (type, frame, start, length,
+ dlbaton->per_cu);
+
+ /* The DW_AT_frame_base attribute contains a location description which
+ computes the base address itself. However, the call to
+ dwarf2_evaluate_loc_desc returns a value representing a variable at
+ that address. The frame base address is thus this variable's
+ address. */
+ return value_address (result);
+ }
+ return 0;
+}
+
/* Vector for inferior functions as represented by LOC_BLOCK, if the inferior
function uses DWARF expression for its DW_AT_frame_base. */
const struct symbol_block_ops dwarf2_block_frame_base_locexpr_funcs =
{
- locexpr_find_frame_base_location
+ locexpr_find_frame_base_location,
+ block_op_get_frame_base
};
/* Implement find_frame_base_location method for LOC_BLOCK functions using
@@ -406,7 +436,8 @@ loclist_find_frame_base_location (struct symbol *framefunc, CORE_ADDR pc,
const struct symbol_block_ops dwarf2_block_frame_base_loclist_funcs =
{
- loclist_find_frame_base_location
+ loclist_find_frame_base_location,
+ block_op_get_frame_base
};
/* See dwarf2loc.h. */
@@ -2396,13 +2427,14 @@ dwarf2_evaluate_loc_desc (struct type *type, struct frame_info *frame,
}
/* Evaluates a dwarf expression and stores the result in VAL, expecting
- that the dwarf expression only produces a single CORE_ADDR. ADDR is a
- context (location of a variable) and might be needed to evaluate the
- location expression.
+ that the dwarf expression only produces a single CORE_ADDR. FRAME is the
+ frame in which the expression is evaluated. ADDR is a context (location of
+ a variable) and might be needed to evaluate the location expression.
Returns 1 on success, 0 otherwise. */
static int
dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton *dlbaton,
+ struct frame_info *frame,
CORE_ADDR addr,
CORE_ADDR *valp)
{
@@ -2417,7 +2449,7 @@ dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton *dlbaton,
ctx = new_dwarf_expr_context ();
cleanup = make_cleanup_free_dwarf_expr_context (ctx);
- baton.frame = get_selected_frame (NULL);
+ baton.frame = frame;
baton.per_cu = dlbaton->per_cu;
baton.obj_address = addr;
@@ -2461,19 +2493,24 @@ dwarf2_locexpr_baton_eval (const struct dwarf2_locexpr_baton *dlbaton,
int
dwarf2_evaluate_property (const struct dynamic_prop *prop,
+ struct frame_info *frame,
struct property_addr_info *addr_stack,
CORE_ADDR *value)
{
if (prop == NULL)
return 0;
+ if (frame == NULL && has_stack_frames ())
+ frame = get_selected_frame (NULL);
+
switch (prop->kind)
{
case PROP_LOCEXPR:
{
const struct dwarf2_property_baton *baton = prop->data.baton;
- if (dwarf2_locexpr_baton_eval (&baton->locexpr, addr_stack->addr,
+ if (dwarf2_locexpr_baton_eval (&baton->locexpr, frame,
+ addr_stack ? addr_stack->addr : 0,
value))
{
if (baton->referenced_type)
@@ -2490,7 +2527,6 @@ dwarf2_evaluate_property (const struct dynamic_prop *prop,
case PROP_LOCLIST:
{
struct dwarf2_property_baton *baton = prop->data.baton;
- struct frame_info *frame = get_selected_frame (NULL);
CORE_ADDR pc = get_frame_address_in_block (frame);
const gdb_byte *data;
struct value *val;
@@ -122,12 +122,19 @@ struct property_addr_info
struct property_addr_info *next;
};
-/* Converts a dynamic property into a static one. ADDR_STACK is the stack
- of addresses that might be needed to evaluate the property.
+/* Converts a dynamic property into a static one. FRAME is the frame in which
+ the property is evaluated; if NULL, the selected frame (if any) is used
+ instead.
+
+ ADDR_STACK is the stack of addresses that might be needed to evaluate the
+ property. When evaluating a property that is not related to a type, it can
+ be NULL.
+
Returns 1 if PROP could be converted and the static value is passed back
into VALUE, otherwise returns 0. */
int dwarf2_evaluate_property (const struct dynamic_prop *prop,
+ struct frame_info *frame,
struct property_addr_info *addr_stack,
CORE_ADDR *value);
@@ -1736,6 +1736,10 @@ static void load_full_type_unit (struct dwarf2_per_cu_data *per_cu);
static void read_signatured_type (struct signatured_type *);
+static int attr_to_dynamic_prop (const struct attribute *attr,
+ struct die_info *die, struct dwarf2_cu *cu,
+ struct dynamic_prop *prop);
+
/* memory allocation interface */
static struct dwarf_block *dwarf_alloc_block (struct dwarf2_cu *);
@@ -11393,6 +11397,16 @@ read_func_scope (struct die_info *die, struct dwarf2_cu *cu)
if (attr)
dwarf2_symbol_mark_computed (attr, newobj->name, cu, 1);
+ /* If there is a location for the static link, record it. */
+ newobj->static_link = NULL;
+ attr = dwarf2_attr (die, DW_AT_static_link, cu);
+ if (attr)
+ {
+ newobj->static_link = obstack_alloc (&objfile->objfile_obstack,
+ sizeof (*newobj->static_link));
+ attr_to_dynamic_prop (attr, die, cu, newobj->static_link);
+ }
+
cu->list_in_scope = &local_symbols;
if (die->child != NULL)
@@ -11443,7 +11457,8 @@ read_func_scope (struct die_info *die, struct dwarf2_cu *cu)
newobj = pop_context ();
/* Make a block for the local symbols within. */
- block = finish_block (newobj->name, &local_symbols, newobj->old_blocks,
+ block = finish_block (newobj->name, &newobj->static_link,
+ &local_symbols, newobj->old_blocks,
lowpc, highpc);
/* For C++, set the block's scope. */
@@ -11529,7 +11544,7 @@ read_lexical_block_scope (struct die_info *die, struct dwarf2_cu *cu)
if (local_symbols != NULL || using_directives != NULL)
{
struct block *block
- = finish_block (0, &local_symbols, newobj->old_blocks,
+ = finish_block (0, NULL, &local_symbols, newobj->old_blocks,
newobj->start_addr, highpc);
/* Note that recording ranges after traversing children, as we
@@ -32,6 +32,7 @@
#include "block.h"
#include "objfiles.h"
#include "language.h"
+#include "dwarf2loc.h"
/* Basic byte-swapping routines. All 'extract' functions return a
host-format integer from a target-format integer at ADDR which is
@@ -409,11 +410,166 @@ minsym_lookup_iterator_cb (struct objfile *objfile, void *cb_data)
return (data->result.minsym != NULL);
}
+/* Given static link expression and the frame it lives in, look for the frame
+ the static links points to and return it. Return NULL if we could not find
+ such a frame. */
+
+static struct frame_info *
+follow_static_link (struct frame_info *frame,
+ const struct dynamic_prop *static_link)
+{
+ CORE_ADDR upper_frame_base;
+
+ if (!dwarf2_evaluate_property (static_link, frame, NULL, &upper_frame_base))
+ return NULL;
+
+ /* Now climb up the stack frame until we reach the frame we are interested
+ in. */
+ for (; frame != NULL; frame = get_prev_frame (frame))
+ {
+ struct symbol *framefunc = get_frame_function (frame);
+
+ /* Protect ourselves against bad things such as circular call stacks. */
+ QUIT;
+
+ /* If we don't know how to compute FRAME's base address, don't give up:
+ maybe the frame we are looking for is upper in the stace frame. */
+ if (framefunc != NULL
+ && SYMBOL_BLOCK_OPS (framefunc)->get_frame_base
+ && (SYMBOL_BLOCK_OPS (framefunc)->get_frame_base (framefunc, frame)
+ == upper_frame_base))
+ break;
+ }
+
+ return frame;
+}
+
+/* Assuming VAR is a symbol that can be reached from FRAME thanks to lexical
+ rules, look for the frame that is actually hosting VAR and return it. If,
+ for some reason, we found no such frame, return NULL.
+
+ This kind of computation is necessary to correctly handle lexically nested
+ functions.
+
+ Note that in some cases, we know what scope VAR comes from but we cannot
+ reach the specific frame that hosts the instance of VAR we are looking for.
+ For backward compatibility purposes (with old compilers), we then look for
+ the first frame that can host it. */
+
+static struct frame_info *
+get_hosting_frame (struct symbol *var, const struct block *var_block,
+ struct frame_info *frame)
+{
+ const struct block *frame_block;
+
+ if (!symbol_read_needs_frame (var))
+ return NULL;
+
+ /* Some symbols for local variables have no block: this happens when they are
+ not produced by a debug information reader, for instance when GDB creates
+ synthetic symbols. Without block information, we must assume they are
+ local to FRAME. In this case, there is nothing to do. */
+ else if (var_block == NULL)
+ return frame;
+
+ /* We currently assume that all symbols with a location list need a frame.
+ This is true in practice because selecting the location description
+ requires to compute the CFA, hence requires a frame. However we have
+ tests that embed global/static symbols with null location lists.
+ We want to get <optimized out> instead of <frame required> when evaluating
+ them so return a frame instead of raising an error. */
+ else if (var_block == block_global_block (var_block)
+ || var_block == block_static_block (var_block))
+ return frame;
+
+ /* We have to handle the "my_func::my_local_var" notation. This requires us
+ to look for upper frames when we find no block for the current frame: here
+ and below, handle when frame_block == NULL. */
+ if (frame != NULL)
+ frame_block = get_frame_block (frame, NULL);
+
+ /* Climb up the call stack until reaching the frame we are looking for. */
+ while (frame != NULL && frame_block != var_block)
+ {
+ /* Protect ourselves against bad things such as circular call stacks. */
+ QUIT;
+
+ if (frame_block == NULL)
+ {
+ frame = get_prev_frame (frame);
+ if (frame == NULL)
+ break;
+ frame_block = get_frame_block (frame, NULL);
+ }
+
+ /* If we failed to find the proper frame, fallback to the heuristic
+ method below. */
+ else if (frame_block == block_global_block (frame_block))
+ {
+ frame = NULL;
+ break;
+ }
+
+ /* Assuming we have a block for this frame: if we are at the function
+ level, the immediate upper lexical block is in an outer function:
+ follow the static link. */
+ else if (BLOCK_FUNCTION (frame_block))
+ {
+ const struct dynamic_prop *static_link
+ = block_static_link (frame_block);
+ int could_climb_up = 0;
+
+ if (static_link != NULL)
+ {
+ frame = follow_static_link (frame, static_link);
+ if (frame != NULL)
+ {
+ frame_block = get_frame_block (frame, NULL);
+ could_climb_up = frame_block != NULL;
+ }
+ }
+ if (!could_climb_up)
+ {
+ frame = NULL;
+ break;
+ }
+ }
+
+ else
+ /* We must be in some function nested lexical block. Just get the
+ outer block: both must share the same frame. */
+ frame_block = BLOCK_SUPERBLOCK (frame_block);
+ }
+
+ /* Old compilers may not provide a static link, or they may provide an
+ invalid one. For such cases, fallback on the old way to evaluate
+ non-local references: just climb up the call stack and pick the first
+ frame that contains the variable we are looking for. */
+ if (frame == NULL)
+ {
+ frame = block_innermost_frame (var_block);
+ if (!frame)
+ {
+ if (BLOCK_FUNCTION (var_block)
+ && !block_inlined_p (var_block)
+ && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (var_block)))
+ error (_("No frame is currently executing in block %s."),
+ SYMBOL_PRINT_NAME (BLOCK_FUNCTION (var_block)));
+ else
+ error (_("No frame is currently executing in specified"
+ " block"));
+ }
+ }
+
+ return frame;
+}
+
/* A default implementation for the "la_read_var_value" hook in
the language vector which should work in most situations. */
struct value *
-default_read_var_value (struct symbol *var, struct frame_info *frame)
+default_read_var_value (struct symbol *var, const struct block *var_block,
+ struct frame_info *frame)
{
struct value *v;
struct type *type = SYMBOL_TYPE (var);
@@ -427,7 +583,10 @@ default_read_var_value (struct symbol *var, struct frame_info *frame)
check_typedef (type);
if (symbol_read_needs_frame (var))
- gdb_assert (frame);
+ gdb_assert (frame != NULL);
+
+ if (frame != NULL)
+ frame = get_hosting_frame (var, var_block, frame);
if (SYMBOL_COMPUTED_OPS (var) != NULL)
return SYMBOL_COMPUTED_OPS (var)->read_variable (var, frame);
@@ -610,14 +769,15 @@ default_read_var_value (struct symbol *var, struct frame_info *frame)
/* Calls VAR's language la_read_var_value hook with the given arguments. */
struct value *
-read_var_value (struct symbol *var, struct frame_info *frame)
+read_var_value (struct symbol *var, const struct block *var_block,
+ struct frame_info *frame)
{
const struct language_defn *lang = language_def (SYMBOL_LANGUAGE (var));
gdb_assert (lang != NULL);
gdb_assert (lang->la_read_var_value != NULL);
- return lang->la_read_var_value (var, frame);
+ return lang->la_read_var_value (var, var_block, frame);
}
/* Install default attributes for register values. */
@@ -1874,7 +1874,7 @@ resolve_dynamic_range (struct type *dyn_range_type,
gdb_assert (TYPE_CODE (dyn_range_type) == TYPE_CODE_RANGE);
prop = &TYPE_RANGE_DATA (dyn_range_type)->low;
- if (dwarf2_evaluate_property (prop, addr_stack, &value))
+ if (dwarf2_evaluate_property (prop, NULL, addr_stack, &value))
{
low_bound.kind = PROP_CONST;
low_bound.data.const_val = value;
@@ -1886,7 +1886,7 @@ resolve_dynamic_range (struct type *dyn_range_type,
}
prop = &TYPE_RANGE_DATA (dyn_range_type)->high;
- if (dwarf2_evaluate_property (prop, addr_stack, &value))
+ if (dwarf2_evaluate_property (prop, NULL, addr_stack, &value))
{
high_bound.kind = PROP_CONST;
high_bound.data.const_val = value;
@@ -2128,7 +2128,8 @@ resolve_dynamic_type_internal (struct type *type,
/* Resolve data_location attribute. */
prop = TYPE_DATA_LOCATION (resolved_type);
- if (prop != NULL && dwarf2_evaluate_property (prop, addr_stack, &value))
+ if (prop != NULL
+ && dwarf2_evaluate_property (prop, NULL, addr_stack, &value))
{
TYPE_DYN_PROP_ADDR (prop) = value;
TYPE_DYN_PROP_KIND (prop) = PROP_CONST;
@@ -1660,7 +1660,7 @@ finish_command_continuation (void *arg, int err)
{
struct value *func;
- func = read_var_value (a->function, get_current_frame ());
+ func = read_var_value (a->function, NULL, get_current_frame ());
TRY
{
/* print_return_value can throw an exception in some
@@ -6082,14 +6082,13 @@ insert_exception_resume_breakpoint (struct thread_info *tp,
{
TRY
{
- struct symbol *vsym;
+ struct symbol_in_block vsym;
struct value *value;
CORE_ADDR handler;
struct breakpoint *bp;
- vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN,
- NULL).symbol;
- value = read_var_value (vsym, frame);
+ vsym = lookup_symbol (SYMBOL_LINKAGE_NAME (sym), b, VAR_DOMAIN, NULL);
+ value = read_var_value (vsym.symbol, vsym.block, frame);
/* If the value was optimized out, revert to the old behavior. */
if (! value_optimized_out (value))
{
@@ -241,13 +241,19 @@ struct language_defn
void (*la_value_print) (struct value *, struct ui_file *,
const struct value_print_options *);
- /* Given a symbol VAR, and a stack frame id FRAME, read the value
- of the variable an return (pointer to a) struct value containing
- the value.
+ /* Given a symbol VAR, the corresponding block VAR_BLOCK (if any) and a
+ stack frame id FRAME, read the value of the variable and return (pointer
+ to a) struct value containing the value.
+
+ VAR_BLOCK is needed if there's a possibility for VAR to be outside
+ FRAME. This is what happens if FRAME correspond to a nested function
+ and VAR is defined in the outer function. If callers know that VAR is
+ located in FRAME, NULL can be passed as VAR_BLOCK.
Throw an error if the variable cannot be found. */
struct value *(*la_read_var_value) (struct symbol *var,
+ const struct block *var_block,
struct frame_info *frame);
/* PC is possibly an unknown languages trampoline.
@@ -199,6 +199,37 @@ set_objfile_main_name (struct objfile *objfile,
objfile->per_bfd->language_of_main = lang;
}
+/* Register STATIC_LINK as the static link for BLOCK, which is part of OBJFILE.
+ Must not be called more than once for each BLOCK. */
+
+void
+objfile_register_static_link (struct objfile *objfile,
+ const struct block *block,
+ struct dynamic_prop *static_link)
+{
+ void **slot;
+
+ if (objfile->static_links == NULL)
+ objfile->static_links = htab_create_alloc
+ (1, htab_hash_pointer, htab_eq_pointer, NULL, xcalloc, xfree);
+
+ slot = htab_find_slot (objfile->static_links, block, INSERT);
+ gdb_assert (*slot == NULL);
+ *slot = static_link;
+}
+
+/* Look for a static link for BLOCK, which is part of OBJFILE. Return NULL if
+ none was found. */
+
+struct dynamic_prop *
+objfile_lookup_static_link (struct objfile *objfile,
+ const struct block *block)
+{
+ if (objfile->static_links == NULL)
+ return NULL;
+ return htab_find (objfile->static_links, block);
+}
+
/* Called via bfd_map_over_sections to build up the section table that
@@ -653,6 +684,11 @@ free_objfile (struct objfile *objfile)
/* Rebuild section map next time we need it. */
get_objfile_pspace_data (objfile->pspace)->section_map_dirty = 1;
+ /* Free the map for static links. There's no need to free static link
+ themselves since they were allocated on the objstack. */
+ if (objfile->static_links != NULL)
+ htab_delete (objfile->static_links);
+
/* The last thing we do is free the objfile struct itself. */
xfree (objfile);
}
@@ -20,6 +20,7 @@
#if !defined (OBJFILES_H)
#define OBJFILES_H
+#include "hashtab.h"
#include "gdb_obstack.h" /* For obstack internals. */
#include "symfile.h" /* For struct psymbol_allocation_list. */
#include "progspace.h"
@@ -412,6 +413,16 @@ struct objfile
table, so we have to keep them here to relocate them
properly. */
struct symbol *template_symbols;
+
+ /* Associate a static link (struct dynamic_prop *) to all blocks (struct
+ block *) that have one. For nested functions, the static link is the
+ expression that computes the frame base of the lexically enclosing
+ function.
+
+ Very few blocks have a static link, so it's more memory efficient to
+ store these here. Static links must be allocated on the objfile's
+ obstack. */
+ struct htab *static_links;
};
/* Defines for the objfile flag word. */
@@ -719,4 +730,11 @@ extern const char *objfile_debug_name (const struct objfile *objfile);
extern void set_objfile_main_name (struct objfile *objfile,
const char *name, enum language lang);
+extern void objfile_register_static_link (struct objfile *objfile,
+ const struct block *block,
+ struct dynamic_prop *static_link);
+
+extern struct dynamic_prop *objfile_lookup_static_link
+ (struct objfile *objfile, const struct block *block);
+
#endif /* !defined (OBJFILES_H) */
@@ -1988,7 +1988,11 @@ print_variable_and_value (const char *name, struct symbol *var,
struct value *val;
struct value_print_options opts;
- val = read_var_value (var, frame);
+ /* READ_VAR_VALUE needs a block in order to deal with non-local
+ references (i.e. to handle nested functions). In this context, we
+ print variables that are local to this frame, so we can avoid passing
+ a block to it. */
+ val = read_var_value (var, NULL, frame);
get_user_print_options (&opts);
opts.deref_ref = 1;
common_val_print (val, stream, indent, &opts, current_language);
@@ -265,7 +265,7 @@ bpfinishpy_init (PyObject *self, PyObject *args, PyObject *kwargs)
/* Ignore Python errors at this stage. */
self_bpfinish->return_type = type_to_type_object (ret_type);
PyErr_Clear ();
- func_value = read_var_value (function, frame);
+ func_value = read_var_value (function, NULL, frame);
self_bpfinish->function_value =
value_to_value_object (func_value);
PyErr_Clear ();
@@ -504,6 +504,7 @@ frapy_read_var (PyObject *self, PyObject *args)
struct frame_info *frame;
PyObject *sym_obj, *block_obj = NULL;
struct symbol *var = NULL; /* gcc-4.3.2 false warning. */
+ const struct block *block = NULL;
struct value *val = NULL;
if (!PyArg_ParseTuple (args, "O|O", &sym_obj, &block_obj))
@@ -514,7 +515,6 @@ frapy_read_var (PyObject *self, PyObject *args)
else if (gdbpy_is_string (sym_obj))
{
char *var_name;
- const struct block *block = NULL;
struct cleanup *cleanup;
var_name = python_string_to_target_string (sym_obj);
@@ -536,11 +536,14 @@ frapy_read_var (PyObject *self, PyObject *args)
TRY
{
+ struct symbol_in_block lookup_sym;
FRAPY_REQUIRE_VALID (self, frame);
if (!block)
block = get_frame_block (frame, NULL);
- var = lookup_symbol (var_name, block, VAR_DOMAIN, NULL).symbol;
+ lookup_sym = lookup_symbol (var_name, block, VAR_DOMAIN, NULL);
+ var = lookup_sym.symbol;
+ block = lookup_sym.block;
}
CATCH (except, RETURN_MASK_ALL)
{
@@ -572,7 +575,7 @@ frapy_read_var (PyObject *self, PyObject *args)
{
FRAPY_REQUIRE_VALID (self, frame);
- val = read_var_value (var, frame);
+ val = read_var_value (var, block, frame);
}
CATCH (except, RETURN_MASK_ALL)
{
@@ -43,16 +43,17 @@ enum mi_print_types
NAME is a pass-through argument where the name of the symbol will
be written. NAME is allocated in this function, but the caller is
responsible for clean up. SYM is a pass-through argument where the
- symbol will be written. In the case of the API returning a string,
- this will be set to NULL. LANGUAGE is also a pass-through argument
- denoting the language attributed to the Symbol. In the case of SYM
- being NULL, this will be set to the current language. Returns
- EXT_LANG_BT_ERROR on error with the appropriate Python exception set, and
- EXT_LANG_BT_OK on success. */
+ symbol will be written and SYM_BLOCK is a pass-through argument to
+ write the block where the symbol lies in. In the case of the API
+ returning a string, this will be set to NULL. LANGUAGE is also a
+ pass-through argument denoting the language attributed to the
+ Symbol. In the case of SYM being NULL, this will be set to the
+ current language. Returns EXT_LANG_BT_ERROR on error with the
+ appropriate Python exception set, and EXT_LANG_BT_OK on success. */
static enum ext_lang_bt_status
extract_sym (PyObject *obj, char **name, struct symbol **sym,
- const struct language_defn **language)
+ struct block **sym_block, const struct language_defn **language)
{
PyObject *result = PyObject_CallMethod (obj, "symbol", NULL);
@@ -75,12 +76,17 @@ extract_sym (PyObject *obj, char **name, struct symbol **sym,
python_language. */
*language = python_language;
*sym = NULL;
+ *sym_block = NULL;
}
else
{
/* This type checks 'result' during the conversion so we
just call it unconditionally and check the return. */
*sym = symbol_object_to_symbol (result);
+ /* TODO: How should we find the corresponding block for this symbol?
+ Should we lookup all blocks in the owning objfile? Should we store
+ the bloc kin the Symbol object? */
+ *sym_block = NULL;
Py_DECREF (result);
@@ -537,10 +543,11 @@ enumerate_args (PyObject *iter,
const struct language_defn *language;
char *sym_name;
struct symbol *sym;
+ struct block *sym_block;
struct value *val;
enum ext_lang_bt_status success = EXT_LANG_BT_ERROR;
- success = extract_sym (item, &sym_name, &sym, &language);
+ success = extract_sym (item, &sym_name, &sym, &sym_block, &language);
if (success == EXT_LANG_BT_ERROR)
{
Py_DECREF (item);
@@ -736,12 +743,13 @@ enumerate_locals (PyObject *iter,
struct value *val;
enum ext_lang_bt_status success = EXT_LANG_BT_ERROR;
struct symbol *sym;
+ struct block *sym_block;
int local_indent = 8 + (8 * indent);
struct cleanup *locals_cleanups;
locals_cleanups = make_cleanup_py_decref (item);
- success = extract_sym (item, &sym_name, &sym, &language);
+ success = extract_sym (item, &sym_name, &sym, &sym_block, &language);
if (success == EXT_LANG_BT_ERROR)
{
do_cleanups (locals_cleanups);
@@ -769,7 +777,7 @@ enumerate_locals (PyObject *iter,
{
TRY
{
- val = read_var_value (sym, frame);
+ val = read_var_value (sym, sym_block, frame);
}
CATCH (except, RETURN_MASK_ERROR)
{
@@ -278,7 +278,10 @@ sympy_value (PyObject *self, PyObject *args)
if (symbol_read_needs_frame (symbol) && frame_info == NULL)
error (_("symbol requires a frame to compute its value"));
- value = read_var_value (symbol, frame_info);
+ /* TODO: How should we find the corresponding block for this symbol?
+ Should we lookup all blocks in the owning objfile? Should we store
+ the block in the Symbol object? */
+ value = read_var_value (symbol, NULL, frame_info);
}
CATCH (except, RETURN_MASK_ALL)
{
@@ -318,7 +318,7 @@ read_frame_local (struct symbol *sym, struct frame_info *frame,
TRY
{
- argp->val = read_var_value (sym, frame);
+ argp->val = read_var_value (sym, NULL, frame);
}
CATCH (except, RETURN_MASK_ERROR)
{
@@ -344,7 +344,7 @@ read_frame_arg (struct symbol *sym, struct frame_info *frame,
{
TRY
{
- val = read_var_value (sym, frame);
+ val = read_var_value (sym, NULL, frame);
}
CATCH (except, RETURN_MASK_ERROR)
{
@@ -471,7 +471,7 @@ read_frame_arg (struct symbol *sym, struct frame_info *frame,
TRY
{
- val = read_var_value (sym, frame);
+ val = read_var_value (sym, NULL, frame);
}
CATCH (except, RETURN_MASK_ERROR)
{
@@ -2424,7 +2424,7 @@ return_command (char *retval_exp, int from_tty)
value_fetch_lazy (return_value);
if (thisfun != NULL)
- function = read_var_value (thisfun, thisframe);
+ function = read_var_value (thisfun, NULL, thisframe);
rv_conv = RETURN_VALUE_REGISTER_CONVENTION;
if (TYPE_CODE (return_type) == TYPE_CODE_VOID)
@@ -665,6 +665,24 @@ struct symbol_block_ops
uninitialized in such case. */
void (*find_frame_base_location) (struct symbol *framefunc, CORE_ADDR pc,
const gdb_byte **start, size_t *length);
+
+ /* Return the frame base address. FRAME is the frame for which we want to
+ compute the base address while FRAMEFUNC is the symbol for the
+ corresponding function.
+
+ This method is designed to work with static links (nested functions
+ handling). Static links are function properties whose evaluation return
+ the frame base address for the enclosing frame. However, there are
+ multiple definitions for "frame base": the content of the frame base
+ register, the CFA as defined by DWARF unwinding information, ...
+
+ So this specific method is supposed to compute the frame base address such
+ as for nested fuctions, the static link computes the same address. For
+ instance, considering DWARF debugging information, the static link is
+ computed with DW_AT_static_link and this method must be used to compute
+ the corresponding DW_AT_frame_base attribute. */
+ CORE_ADDR (*get_frame_base) (struct symbol *framefunc,
+ struct frame_info *frame);
};
/* Functions used with LOC_REGISTER and LOC_REGPARM_ADDR. */
new file mode 100644
@@ -0,0 +1,37 @@
+/* This test program is part of GDB, the GNU debugger.
+
+ Copyright 2015 Free Software Foundation, Inc.
+
+ 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 3 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, see <http://www.gnu.org/licenses/>. */
+
+int
+foo (int i1)
+{
+ int
+ nested (int i2)
+ {
+ /* Here with i1 and i2, we can test that GDB can fetch both a local and a
+ non-local variable in the most simple nested function situation: the
+ parent block instance is accessible as the directly upper frame. */
+ return i1 * i2; /* STOP */
+ }
+
+ return nested (i1 + 1);
+}
+
+int
+main ()
+{
+ return !foo (1);
+}
new file mode 100644
@@ -0,0 +1,55 @@
+# Copyright 2015 Free Software Foundation, Inc.
+
+# 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 3 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, see <http://www.gnu.org/licenses/>.
+
+# This file is part of the gdb testsuite.
+
+#
+# Test nested functions related functionality.
+#
+
+standard_testfile
+
+
+set testcase "nested-subp1"
+
+if { [gdb_compile "${srcdir}/${subdir}/${testcase}.c" \
+ [standard_output_file "${testcase}"] \
+ "${testcase}" \
+ [list debug "additional_flags=-std=gnu99"]] != "" } {
+ return -1
+}
+
+
+# Run until the variables we are interested in are visible.
+
+clean_restart "${testcase}"
+if ![runto_main] {
+ perror "could not run to main"
+ continue
+}
+
+set bp_location [gdb_get_line_number "STOP" "${testcase}.c"]
+gdb_test "break ${testcase}.c:${bp_location}" \
+ "Breakpoint \[0-9\]+ at 0x\[0-9a-fA-F\]+: .*" \
+ "breakpoint to the STOP marker"
+gdb_test "continue" \
+ "Breakpoint \[0-9\]+, nested .*" \
+ "continue to the STOP marker"
+
+
+# Check we get correct values for both local and non-local variable references.
+
+gdb_test "print i1" "1"
+gdb_test "print i2" "2"
new file mode 100644
@@ -0,0 +1,48 @@
+/* This test program is part of GDB, the GNU debugger.
+
+ Copyright 2015 Free Software Foundation, Inc.
+
+ 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 3 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, see <http://www.gnu.org/licenses/>. */
+
+void
+iter_str (const char *str, void (*callback) (char c))
+{
+ for (; *str != '\0'; ++str)
+ callback (*str);
+}
+
+int
+length_str (const char *str)
+{
+ int count = 0;
+
+ void
+ increment (char c)
+ {
+ /* Here with COUNT, we can test that GDB can read a non-local variable even
+ though it's not directly in the upper stack frame. */
+ count += 1; /* STOP */
+ }
+
+ iter_str (str, &increment);
+ return count;
+}
+
+int
+main ()
+{
+ if (length_str ("foo") == 3)
+ return 0;
+ return 1;
+}
new file mode 100644
@@ -0,0 +1,64 @@
+# Copyright 2015 Free Software Foundation, Inc.
+
+# 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 3 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, see <http://www.gnu.org/licenses/>.
+
+# This file is part of the gdb testsuite.
+
+#
+# Test nested functions related functionality.
+#
+
+standard_testfile
+
+
+set testcase "nested-subp2"
+
+if { [gdb_compile "${srcdir}/${subdir}/${testcase}.c" \
+ [standard_output_file "${testcase}"] \
+ "${testcase}" \
+ [list debug "additional_flags=-std=gnu99"]] != "" } {
+ return -1
+}
+
+
+# Run until the variables we are interested in are visible.
+
+clean_restart "${testcase}"
+if ![runto_main] {
+ perror "could not run to main"
+ continue
+}
+
+set bp_location [gdb_get_line_number "STOP" "${testcase}.c"]
+gdb_test "break ${testcase}.c:${bp_location}" \
+ "Breakpoint \[0-9\]+ at 0x\[0-9a-fA-F\]+: .*" \
+ "breakpoint to the STOP marker"
+gdb_test "continue" \
+ "Breakpoint \[0-9\]+, increment .*" \
+ "continue to the STOP marker"
+
+
+# Check we get correct values for both local and non-local variable references.
+
+gdb_test "print c" "102 'f'"
+gdb_test "print count" "0"
+
+
+# Same but a little later: make sure we were looking at the proper places.
+
+gdb_test "continue" \
+ "Breakpoint \[0-9\]+, increment .*" \
+ "continue to the STOP marker"
+gdb_test "print c" "111 'o'"
+gdb_test "print count" "1"
new file mode 100644
@@ -0,0 +1,66 @@
+/* This test program is part of GDB, the GNU debugger.
+
+ Copyright 2015 Free Software Foundation, Inc.
+
+ 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 3 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, see <http://www.gnu.org/licenses/>. */
+
+#include <stdlib.h>
+
+typedef void (*callback_t) (void);
+
+extern void process (callback_t cb);
+extern void parent (int first, callback_t cb);
+
+void
+ignore (int unused)
+{
+ (void) unused;
+}
+
+void
+process (callback_t cb)
+{
+ parent (0, cb);
+}
+
+void
+parent (int first, callback_t cb)
+{
+ void child (void)
+ {
+ /* When reaching this, there are two block instances for PARENT on the
+ stack: the one that is right in the upper frame is not the one actually
+ used for non-local references, so GDB has to follow the static link in
+ order to get the correct instance, and thus in order to read the proper
+ variables.
+
+ As a simple check, we can verify that under GDB, the following is true:
+ parent_first == first (which should be one: see the IF block below). */
+ const int parent_first = first;
+ ignore (parent_first); /* STOP */
+ ignore (first);
+ }
+
+ if (first)
+ process (&child);
+ else
+ cb ();
+}
+
+int
+main ()
+{
+ parent (1, NULL);
+ return 0;
+}
new file mode 100644
@@ -0,0 +1,55 @@
+# Copyright 2015 Free Software Foundation, Inc.
+
+# 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 3 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, see <http://www.gnu.org/licenses/>.
+
+# This file is part of the gdb testsuite.
+
+#
+# Test nested functions related functionality.
+#
+
+standard_testfile
+
+
+set testcase "nested-subp3"
+
+if { [gdb_compile "${srcdir}/${subdir}/${testcase}.c" \
+ [standard_output_file "${testcase}"] \
+ "${testcase}" \
+ [list debug "additional_flags=-std=gnu99"]] != "" } {
+ return -1
+}
+
+
+# Run until the variables we are interested in are visible.
+
+clean_restart "${testcase}"
+if ![runto_main] {
+ perror "could not run to main"
+ continue
+}
+
+set bp_location [gdb_get_line_number "STOP" "${testcase}.c"]
+gdb_test "break ${testcase}.c:${bp_location}" \
+ "Breakpoint \[0-9\]+ at 0x\[0-9a-fA-F\]+: .*" \
+ "breakpoint to the STOP marker"
+gdb_test "continue" \
+ "Breakpoint \[0-9\]+, child .*" \
+ "continue to the STOP marker"
+
+
+# Check we get correct values for both local and non-local variable references.
+
+gdb_test "print first" "1"
+gdb_test "print parent_first" "1"
@@ -1288,27 +1288,12 @@ value_repeat (struct value *arg1, int count)
struct value *
value_of_variable (struct symbol *var, const struct block *b)
{
- struct frame_info *frame;
+ struct frame_info *frame = NULL;
- if (!symbol_read_needs_frame (var))
- frame = NULL;
- else if (!b)
+ if (symbol_read_needs_frame (var))
frame = get_selected_frame (_("No frame selected."));
- else
- {
- frame = block_innermost_frame (b);
- if (!frame)
- {
- if (BLOCK_FUNCTION (b) && !block_inlined_p (b)
- && SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)))
- error (_("No frame is currently executing in block %s."),
- SYMBOL_PRINT_NAME (BLOCK_FUNCTION (b)));
- else
- error (_("No frame is currently executing in specified block"));
- }
- }
- return read_var_value (var, frame);
+ return read_var_value (var, b, frame);
}
struct value *
@@ -3459,9 +3444,9 @@ value_struct_elt_for_reference (struct type *domain, int offset,
return NULL;
if (want_address)
- return value_addr (read_var_value (s, 0));
+ return value_addr (read_var_value (s, 0, 0));
else
- return read_var_value (s, 0);
+ return read_var_value (s, 0, 0);
}
if (TYPE_FN_FIELD_VIRTUAL_P (f, j))
@@ -3489,7 +3474,7 @@ value_struct_elt_for_reference (struct type *domain, int offset,
if (s == NULL)
return NULL;
- v = read_var_value (s, 0);
+ v = read_var_value (s, 0, 0);
if (!want_address)
result = v;
else
@@ -3725,7 +3710,7 @@ value_full_object (struct value *argp,
struct value *
value_of_this (const struct language_defn *lang)
{
- struct symbol *sym;
+ struct symbol_in_block sym;
const struct block *b;
struct frame_info *frame;
@@ -3736,12 +3721,12 @@ value_of_this (const struct language_defn *lang)
b = get_frame_block (frame, NULL);
- sym = lookup_language_this (lang, b).symbol;
- if (sym == NULL)
+ sym = lookup_language_this (lang, b);
+ if (sym.symbol == NULL)
error (_("current stack frame does not contain a variable named `%s'"),
lang->la_name_of_this);
- return read_var_value (sym, frame);
+ return read_var_value (sym.symbol, sym.block, frame);
}
/* Return the value of the local variable, if one exists. Return NULL
@@ -670,9 +670,11 @@ struct value *value_of_register_lazy (struct frame_info *frame, int regnum);
extern int symbol_read_needs_frame (struct symbol *);
extern struct value *read_var_value (struct symbol *var,
+ const struct block *var_block,
struct frame_info *frame);
extern struct value *default_read_var_value (struct symbol *var,
+ const struct block *var_block,
struct frame_info *frame);
extern struct value *allocate_value (struct type *type);
@@ -1388,8 +1388,8 @@ read_xcoff_symtab (struct objfile *objfile, struct partial_symtab *pst)
break;
}
- finish_block (newobj->name, &local_symbols, newobj->old_blocks,
- newobj->start_addr,
+ finish_block (newobj->name, NULL, &local_symbols,
+ newobj->old_blocks, newobj->start_addr,
(fcn_cs_saved.c_value
+ fcn_aux_saved.x_sym.x_misc.x_fsize
+ ANOFFSET (objfile->section_offsets,
--
2.4.5