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[binutils-gdb] Don't assume break/continue inside a TRY block works
- From: Pedro Alves <palves at sourceware dot org>
- To: gdb-cvs at sourceware dot org
- Date: 29 Oct 2015 12:56:45 -0000
- Subject: [binutils-gdb] Don't assume break/continue inside a TRY block works
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=9c6595ab6873e15fe533b05bb7b98c11f17c5d57
commit 9c6595ab6873e15fe533b05bb7b98c11f17c5d57
Author: Pedro Alves <palves@redhat.com>
Date: Thu Oct 29 12:55:01 2015 +0000
Don't assume break/continue inside a TRY block works
In C++, this:
try
{
break;
}
catch (..)
{}
is invalid. However, because our TRY/CATCH macros support it in C,
the C++ version of those macros support it too. To catch such
assumptions, this adds a (disabled) hack that maps TRY/CATCH to raw
C++ try/catch. Then it goes through all instances that building on
x86_64 GNU/Linux trips on, fixing them.
This isn't strictly necessary yet, but I think it's nicer to try to
keep the tree in a state where it's easier to eliminate the TRY/CATCH
macros.
gdb/ChangeLog:
2015-10-29 Pedro Alves <palves@redhat.com>
* dwarf2-frame-tailcall.c (dwarf2_tailcall_sniffer_first): Don't
assume that "break" breaks out of a TRY/CATCH.
* python/py-framefilter.c (py_print_single_arg): Don't assume
"continue" breaks out of a TRY/CATCH.
* python/py-value.c (valpy_binop_throw): New function, factored
out from ...
(valpy_binop): ... this.
(valpy_richcompare_throw): New function, factored
out from ...
(valpy_richcompare): ... this.
* solib.c (solib_read_symbols): Don't assume "break" breaks out
of a TRY/CATCH.
* common/common-exceptions.h [USE_RAW_CXX_TRY]
<TRY/CATCH/END_CATCH>: Define as 1-1 wrappers around try/catch.
Diff:
---
gdb/ChangeLog | 17 +++
gdb/common/common-exceptions.h | 16 ++
gdb/dwarf2-frame-tailcall.c | 16 +-
gdb/python/py-framefilter.c | 46 +++---
gdb/python/py-value.c | 340 ++++++++++++++++++++++-------------------
gdb/solib.c | 20 +--
6 files changed, 261 insertions(+), 194 deletions(-)
diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 7209666..27712b3 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,20 @@
+2015-10-29 Pedro Alves <palves@redhat.com>
+
+ * dwarf2-frame-tailcall.c (dwarf2_tailcall_sniffer_first): Don't
+ assume that "break" breaks out of a TRY/CATCH.
+ * python/py-framefilter.c (py_print_single_arg): Don't assume
+ "continue" breaks out of a TRY/CATCH.
+ * python/py-value.c (valpy_binop_throw): New function, factored
+ out from ...
+ (valpy_binop): ... this.
+ (valpy_richcompare_throw): New function, factored
+ out from ...
+ (valpy_richcompare): ... this.
+ * solib.c (solib_read_symbols): Don't assume "break" breaks out
+ of a TRY/CATCH.
+ * common/common-exceptions.h [USE_RAW_CXX_TRY]
+ <TRY/CATCH/END_CATCH>: Define as 1-1 wrappers around try/catch.
+
2015-10-28 Simon Dardis <Simon.Dardis@imgtec.com>
* mips-linux-tdep.c (mips_linux_in_dynsym_stub): Recognise 'or'
diff --git a/gdb/common/common-exceptions.h b/gdb/common/common-exceptions.h
index 2e6a6d9..51795b1 100644
--- a/gdb/common/common-exceptions.h
+++ b/gdb/common/common-exceptions.h
@@ -195,6 +195,14 @@ struct exception_try_scope
void *saved_state;
};
+/* Define this to build with TRY/CATCH mapped directly to raw
+ try/catch. GDB won't work correctly, but building that way catches
+ code tryin to break/continue out of the try block, along with
+ spurious code between the TRY and the CATCH block. */
+//#define USE_RAW_CXX_TRY
+
+#ifndef USE_RAW_CXX_TRY
+
/* We still need to wrap TRY/CATCH in C++ so that cleanups and C++
exceptions can coexist. The TRY blocked is wrapped in a
do/while(0) so that break/continue within the block works the same
@@ -216,6 +224,14 @@ struct exception_try_scope
{ \
exception_rethrow (); \
}
+#else
+
+#define TRY try
+#define CATCH(EXCEPTION, MASK) \
+ catch (struct gdb_exception ## _ ## MASK &EXCEPTION)
+#define END_CATCH
+
+#endif
/* The exception types client code may catch. They're just shims
around gdb_exception that add nothing but type info. Which is used
diff --git a/gdb/dwarf2-frame-tailcall.c b/gdb/dwarf2-frame-tailcall.c
index 952bc14..613cc34 100644
--- a/gdb/dwarf2-frame-tailcall.c
+++ b/gdb/dwarf2-frame-tailcall.c
@@ -386,13 +386,15 @@ dwarf2_tailcall_sniffer_first (struct frame_info *this_frame,
/* call_site_find_chain can throw an exception. */
chain = call_site_find_chain (prev_gdbarch, prev_pc, this_pc);
- if (entry_cfa_sp_offsetp == NULL)
- break;
- sp_regnum = gdbarch_sp_regnum (prev_gdbarch);
- if (sp_regnum == -1)
- break;
- prev_sp = frame_unwind_register_unsigned (this_frame, sp_regnum);
- prev_sp_p = 1;
+ if (entry_cfa_sp_offsetp != NULL)
+ {
+ sp_regnum = gdbarch_sp_regnum (prev_gdbarch);
+ if (sp_regnum != -1)
+ {
+ prev_sp = frame_unwind_register_unsigned (this_frame, sp_regnum);
+ prev_sp_p = 1;
+ }
+ }
}
CATCH (except, RETURN_MASK_ERROR)
{
diff --git a/gdb/python/py-framefilter.c b/gdb/python/py-framefilter.c
index ac97723..0f8dc62 100644
--- a/gdb/python/py-framefilter.c
+++ b/gdb/python/py-framefilter.c
@@ -448,37 +448,39 @@ py_print_single_arg (struct ui_out *out,
{
retval = EXT_LANG_BT_ERROR;
do_cleanups (cleanups);
- continue;
}
}
- if (val != NULL)
- annotate_arg_value (value_type (val));
-
- /* If the output is to the CLI, and the user option "set print
- frame-arguments" is set to none, just output "...". */
- if (! ui_out_is_mi_like_p (out) && args_type == NO_VALUES)
- ui_out_field_string (out, "value", "...");
- else
+ if (retval != EXT_LANG_BT_ERROR)
{
- /* Otherwise, print the value for both MI and the CLI, except
- for the case of MI_PRINT_NO_VALUES. */
- if (args_type != NO_VALUES)
+ if (val != NULL)
+ annotate_arg_value (value_type (val));
+
+ /* If the output is to the CLI, and the user option "set print
+ frame-arguments" is set to none, just output "...". */
+ if (! ui_out_is_mi_like_p (out) && args_type == NO_VALUES)
+ ui_out_field_string (out, "value", "...");
+ else
{
- if (val == NULL)
+ /* Otherwise, print the value for both MI and the CLI, except
+ for the case of MI_PRINT_NO_VALUES. */
+ if (args_type != NO_VALUES)
{
- gdb_assert (fa != NULL && fa->error != NULL);
- ui_out_field_fmt (out, "value",
- _("<error reading variable: %s>"),
- fa->error);
+ if (val == NULL)
+ {
+ gdb_assert (fa != NULL && fa->error != NULL);
+ ui_out_field_fmt (out, "value",
+ _("<error reading variable: %s>"),
+ fa->error);
+ }
+ else if (py_print_value (out, val, opts, 0, args_type, language)
+ == EXT_LANG_BT_ERROR)
+ retval = EXT_LANG_BT_ERROR;
}
- else if (py_print_value (out, val, opts, 0, args_type, language)
- == EXT_LANG_BT_ERROR)
- retval = EXT_LANG_BT_ERROR;
}
- }
- do_cleanups (cleanups);
+ do_cleanups (cleanups);
+ }
}
CATCH (except, RETURN_MASK_ERROR)
{
diff --git a/gdb/python/py-value.c b/gdb/python/py-value.c
index ac6b224..140aaf5 100644
--- a/gdb/python/py-value.c
+++ b/gdb/python/py-value.c
@@ -1018,133 +1018,147 @@ enum valpy_opcode
#define STRIP_REFERENCE(TYPE) \
((TYPE_CODE (TYPE) == TYPE_CODE_REF) ? (TYPE_TARGET_TYPE (TYPE)) : (TYPE))
-/* Returns a value object which is the result of applying the operation
- specified by OPCODE to the given arguments. Returns NULL on error, with
- a python exception set. */
+/* Helper for valpy_binop. Returns a value object which is the result
+ of applying the operation specified by OPCODE to the given
+ arguments. Throws a GDB exception on error. */
+
static PyObject *
-valpy_binop (enum valpy_opcode opcode, PyObject *self, PyObject *other)
+valpy_binop_throw (enum valpy_opcode opcode, PyObject *self, PyObject *other)
{
PyObject *result = NULL;
- TRY
+ struct value *arg1, *arg2;
+ struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
+ struct value *res_val = NULL;
+ enum exp_opcode op = OP_NULL;
+ int handled = 0;
+
+ /* If the gdb.Value object is the second operand, then it will be
+ passed to us as the OTHER argument, and SELF will be an entirely
+ different kind of object, altogether. Because of this, we can't
+ assume self is a gdb.Value object and need to convert it from
+ python as well. */
+ arg1 = convert_value_from_python (self);
+ if (arg1 == NULL)
{
- struct value *arg1, *arg2;
- struct cleanup *cleanup = make_cleanup_value_free_to_mark (value_mark ());
- struct value *res_val = NULL;
- enum exp_opcode op = OP_NULL;
- int handled = 0;
-
- /* If the gdb.Value object is the second operand, then it will be passed
- to us as the OTHER argument, and SELF will be an entirely different
- kind of object, altogether. Because of this, we can't assume self is
- a gdb.Value object and need to convert it from python as well. */
- arg1 = convert_value_from_python (self);
- if (arg1 == NULL)
- {
- do_cleanups (cleanup);
- break;
- }
+ do_cleanups (cleanup);
+ return NULL;
+ }
- arg2 = convert_value_from_python (other);
- if (arg2 == NULL)
- {
- do_cleanups (cleanup);
- break;
- }
+ arg2 = convert_value_from_python (other);
+ if (arg2 == NULL)
+ {
+ do_cleanups (cleanup);
+ return NULL;
+ }
- switch (opcode)
- {
- case VALPY_ADD:
+ switch (opcode)
+ {
+ case VALPY_ADD:
+ {
+ struct type *ltype = value_type (arg1);
+ struct type *rtype = value_type (arg2);
+
+ ltype = check_typedef (ltype);
+ ltype = STRIP_REFERENCE (ltype);
+ rtype = check_typedef (rtype);
+ rtype = STRIP_REFERENCE (rtype);
+
+ handled = 1;
+ if (TYPE_CODE (ltype) == TYPE_CODE_PTR
+ && is_integral_type (rtype))
+ res_val = value_ptradd (arg1, value_as_long (arg2));
+ else if (TYPE_CODE (rtype) == TYPE_CODE_PTR
+ && is_integral_type (ltype))
+ res_val = value_ptradd (arg2, value_as_long (arg1));
+ else
{
- struct type *ltype = value_type (arg1);
- struct type *rtype = value_type (arg2);
-
- ltype = check_typedef (ltype);
- ltype = STRIP_REFERENCE (ltype);
- rtype = check_typedef (rtype);
- rtype = STRIP_REFERENCE (rtype);
-
- handled = 1;
- if (TYPE_CODE (ltype) == TYPE_CODE_PTR
- && is_integral_type (rtype))
- res_val = value_ptradd (arg1, value_as_long (arg2));
- else if (TYPE_CODE (rtype) == TYPE_CODE_PTR
- && is_integral_type (ltype))
- res_val = value_ptradd (arg2, value_as_long (arg1));
- else
- {
- handled = 0;
- op = BINOP_ADD;
- }
+ handled = 0;
+ op = BINOP_ADD;
}
- break;
- case VALPY_SUB:
+ }
+ break;
+ case VALPY_SUB:
+ {
+ struct type *ltype = value_type (arg1);
+ struct type *rtype = value_type (arg2);
+
+ ltype = check_typedef (ltype);
+ ltype = STRIP_REFERENCE (ltype);
+ rtype = check_typedef (rtype);
+ rtype = STRIP_REFERENCE (rtype);
+
+ handled = 1;
+ if (TYPE_CODE (ltype) == TYPE_CODE_PTR
+ && TYPE_CODE (rtype) == TYPE_CODE_PTR)
+ /* A ptrdiff_t for the target would be preferable here. */
+ res_val = value_from_longest (builtin_type_pyint,
+ value_ptrdiff (arg1, arg2));
+ else if (TYPE_CODE (ltype) == TYPE_CODE_PTR
+ && is_integral_type (rtype))
+ res_val = value_ptradd (arg1, - value_as_long (arg2));
+ else
{
- struct type *ltype = value_type (arg1);
- struct type *rtype = value_type (arg2);
-
- ltype = check_typedef (ltype);
- ltype = STRIP_REFERENCE (ltype);
- rtype = check_typedef (rtype);
- rtype = STRIP_REFERENCE (rtype);
-
- handled = 1;
- if (TYPE_CODE (ltype) == TYPE_CODE_PTR
- && TYPE_CODE (rtype) == TYPE_CODE_PTR)
- /* A ptrdiff_t for the target would be preferable here. */
- res_val = value_from_longest (builtin_type_pyint,
- value_ptrdiff (arg1, arg2));
- else if (TYPE_CODE (ltype) == TYPE_CODE_PTR
- && is_integral_type (rtype))
- res_val = value_ptradd (arg1, - value_as_long (arg2));
- else
- {
- handled = 0;
- op = BINOP_SUB;
- }
+ handled = 0;
+ op = BINOP_SUB;
}
- break;
- case VALPY_MUL:
- op = BINOP_MUL;
- break;
- case VALPY_DIV:
- op = BINOP_DIV;
- break;
- case VALPY_REM:
- op = BINOP_REM;
- break;
- case VALPY_POW:
- op = BINOP_EXP;
- break;
- case VALPY_LSH:
- op = BINOP_LSH;
- break;
- case VALPY_RSH:
- op = BINOP_RSH;
- break;
- case VALPY_BITAND:
- op = BINOP_BITWISE_AND;
- break;
- case VALPY_BITOR:
- op = BINOP_BITWISE_IOR;
- break;
- case VALPY_BITXOR:
- op = BINOP_BITWISE_XOR;
- break;
- }
+ }
+ break;
+ case VALPY_MUL:
+ op = BINOP_MUL;
+ break;
+ case VALPY_DIV:
+ op = BINOP_DIV;
+ break;
+ case VALPY_REM:
+ op = BINOP_REM;
+ break;
+ case VALPY_POW:
+ op = BINOP_EXP;
+ break;
+ case VALPY_LSH:
+ op = BINOP_LSH;
+ break;
+ case VALPY_RSH:
+ op = BINOP_RSH;
+ break;
+ case VALPY_BITAND:
+ op = BINOP_BITWISE_AND;
+ break;
+ case VALPY_BITOR:
+ op = BINOP_BITWISE_IOR;
+ break;
+ case VALPY_BITXOR:
+ op = BINOP_BITWISE_XOR;
+ break;
+ }
+
+ if (!handled)
+ {
+ if (binop_user_defined_p (op, arg1, arg2))
+ res_val = value_x_binop (arg1, arg2, op, OP_NULL, EVAL_NORMAL);
+ else
+ res_val = value_binop (arg1, arg2, op);
+ }
- if (!handled)
- {
- if (binop_user_defined_p (op, arg1, arg2))
- res_val = value_x_binop (arg1, arg2, op, OP_NULL, EVAL_NORMAL);
- else
- res_val = value_binop (arg1, arg2, op);
- }
+ if (res_val)
+ result = value_to_value_object (res_val);
- if (res_val)
- result = value_to_value_object (res_val);
+ do_cleanups (cleanup);
+ return result;
+}
- do_cleanups (cleanup);
+/* Returns a value object which is the result of applying the operation
+ specified by OPCODE to the given arguments. Returns NULL on error, with
+ a python exception set. */
+static PyObject *
+valpy_binop (enum valpy_opcode opcode, PyObject *self, PyObject *other)
+{
+ PyObject *result = NULL;
+
+ TRY
+ {
+ result = valpy_binop_throw (opcode, self, other);
}
CATCH (except, RETURN_MASK_ALL)
{
@@ -1351,6 +1365,63 @@ valpy_xor (PyObject *self, PyObject *other)
return valpy_binop (VALPY_BITXOR, self, other);
}
+/* Helper for valpy_richcompare. Implements comparison operations for
+ value objects. Returns true/false on success. Returns -1 with a
+ Python exception set if a Python error is detected. Throws a GDB
+ exception on other errors (memory error, etc.). */
+
+static int
+valpy_richcompare_throw (PyObject *self, PyObject *other, int op)
+{
+ int result;
+ struct value *value_other;
+ struct value *value_self;
+ struct value *mark = value_mark ();
+ struct cleanup *cleanup;
+
+ value_other = convert_value_from_python (other);
+ if (value_other == NULL)
+ return -1;
+
+ cleanup = make_cleanup_value_free_to_mark (mark);
+
+ value_self = ((value_object *) self)->value;
+
+ switch (op)
+ {
+ case Py_LT:
+ result = value_less (value_self, value_other);
+ break;
+ case Py_LE:
+ result = value_less (value_self, value_other)
+ || value_equal (value_self, value_other);
+ break;
+ case Py_EQ:
+ result = value_equal (value_self, value_other);
+ break;
+ case Py_NE:
+ result = !value_equal (value_self, value_other);
+ break;
+ case Py_GT:
+ result = value_less (value_other, value_self);
+ break;
+ case Py_GE:
+ result = (value_less (value_other, value_self)
+ || value_equal (value_self, value_other));
+ break;
+ default:
+ /* Can't happen. */
+ PyErr_SetString (PyExc_NotImplementedError,
+ _("Invalid operation on gdb.Value."));
+ result = -1;
+ break;
+ }
+
+ do_cleanups (cleanup);
+ return result;
+}
+
+
/* Implements comparison operations for value objects. Returns NULL on error,
with a python exception set. */
static PyObject *
@@ -1379,48 +1450,7 @@ valpy_richcompare (PyObject *self, PyObject *other, int op)
TRY
{
- struct value *value_other, *mark = value_mark ();
- struct cleanup *cleanup;
-
- value_other = convert_value_from_python (other);
- if (value_other == NULL)
- {
- result = -1;
- break;
- }
-
- cleanup = make_cleanup_value_free_to_mark (mark);
-
- switch (op) {
- case Py_LT:
- result = value_less (((value_object *) self)->value, value_other);
- break;
- case Py_LE:
- result = value_less (((value_object *) self)->value, value_other)
- || value_equal (((value_object *) self)->value, value_other);
- break;
- case Py_EQ:
- result = value_equal (((value_object *) self)->value, value_other);
- break;
- case Py_NE:
- result = !value_equal (((value_object *) self)->value, value_other);
- break;
- case Py_GT:
- result = value_less (value_other, ((value_object *) self)->value);
- break;
- case Py_GE:
- result = value_less (value_other, ((value_object *) self)->value)
- || value_equal (((value_object *) self)->value, value_other);
- break;
- default:
- /* Can't happen. */
- PyErr_SetString (PyExc_NotImplementedError,
- _("Invalid operation on gdb.Value."));
- result = -1;
- break;
- }
-
- do_cleanups (cleanup);
+ result = valpy_richcompare_throw (self, other, op);
}
CATCH (except, RETURN_MASK_ALL)
{
diff --git a/gdb/solib.c b/gdb/solib.c
index ca2c9ab..d715897 100644
--- a/gdb/solib.c
+++ b/gdb/solib.c
@@ -696,16 +696,16 @@ solib_read_symbols (struct so_list *so, int flags)
&& so->objfile->addr_low == so->addr_low)
break;
}
- if (so->objfile != NULL)
- break;
-
- sap = build_section_addr_info_from_section_table (so->sections,
- so->sections_end);
- so->objfile = symbol_file_add_from_bfd (so->abfd, so->so_name,
- flags, sap, OBJF_SHARED,
- NULL);
- so->objfile->addr_low = so->addr_low;
- free_section_addr_info (sap);
+ if (so->objfile == NULL)
+ {
+ sap = build_section_addr_info_from_section_table (so->sections,
+ so->sections_end);
+ so->objfile = symbol_file_add_from_bfd (so->abfd, so->so_name,
+ flags, sap, OBJF_SHARED,
+ NULL);
+ so->objfile->addr_low = so->addr_low;
+ free_section_addr_info (sap);
+ }
so->symbols_loaded = 1;
}