procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

c-common.c (handle_bnd_variable_size_attribute): New.

Browse source 
* c-family/c-common.c (handle_bnd_variable_size_attribute): New.
        (handle_bnd_legacy): New.
        (c_common_attribute_table): Add bnd_variable_size and bnd_legacy.
        * doc/extend.texi: Document bnd_variable_size and bnd_legacy
        attributes.

From-SVN: r204197
This commit is contained in:
Ilya Enkovich 2013-10-30 09:07:24 +00:00 • committed by Kirill Yukhin
parent 109719ebd4
commit 2017035a60
3 changed files with 87 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
gcc/ChangeLog
View file

@ -1,3 +1,11 @@
2013-10-30 Ilya Enkovich <ilya.enkovich@intel.com>
* c-family/c-common.c (handle_bnd_variable_size_attribute): New.
(handle_bnd_legacy): New.
(c_common_attribute_table): Add bnd_variable_size and bnd_legacy.
* doc/extend.texi: Document bnd_variable_size and bnd_legacy
attributes.
2013-10-29 Ilya Enkovich <ilya.enkovich@intel.com>
* builtin-types.def (BT_FN_VOID_CONST_PTR): New.

38
gcc/c-family/c-common.c
View file

@ -375,6 +375,8 @@ static tree handle_omp_declare_simd_attribute (tree *, tree, tree, int,
bool *);
static tree handle_omp_declare_target_attribute (tree *, tree, tree, int,
bool *);
static tree handle_bnd_variable_size_attribute (tree *, tree, tree, int, bool *);
static tree handle_bnd_legacy (tree *, tree, tree, int, bool *);
static void check_function_nonnull (tree, int, tree *);
static void check_nonnull_arg (void *, tree, unsigned HOST_WIDE_INT);
@ -759,6 +761,10 @@ const struct attribute_spec c_common_attribute_table[] =
handle_omp_declare_simd_attribute, false },
{ "omp declare target", 0, 0, true, false, false,
handle_omp_declare_target_attribute, false },
{ "bnd_variable_size", 0, 0, true, false, false,
handle_bnd_variable_size_attribute, false },
{ "bnd_legacy", 0, 0, true, false, false,
handle_bnd_legacy, false },
{ NULL, 0, 0, false, false, false, NULL, false }
};
@ -8018,6 +8024,38 @@ handle_fnspec_attribute (tree *node ATTRIBUTE_UNUSED, tree ARG_UNUSED (name),
return NULL_TREE;
}
/* Handle a "bnd_variable_size" attribute; arguments as in
struct attribute_spec.handler. */
static tree
handle_bnd_variable_size_attribute (tree *node, tree name, tree ARG_UNUSED (args),
int ARG_UNUSED (flags), bool *no_add_attrs)
{
if (TREE_CODE (*node) != FIELD_DECL)
{
warning (OPT_Wattributes, "%qE attribute ignored", name);
*no_add_attrs = true;
}
return NULL_TREE;
}
/* Handle a "bnd_legacy" attribute; arguments as in
struct attribute_spec.handler. */
static tree
handle_bnd_legacy (tree *node, tree name, tree ARG_UNUSED (args),
int ARG_UNUSED (flags), bool *no_add_attrs)
{
if (TREE_CODE (*node) != FUNCTION_DECL)
{
warning (OPT_Wattributes, "%qE attribute ignored", name);
*no_add_attrs = true;
}
return NULL_TREE;
}
/* Handle a "warn_unused" attribute; arguments as in
struct attribute_spec.handler. */

47
gcc/doc/extend.texi
View file

@ -2138,7 +2138,7 @@ attributes are currently defined for functions on all targets:
@code{returns_nonnull}, @code{gnu_inline},
@code{externally_visible}, @code{hot}, @code{cold}, @code{artificial},
@code{no_sanitize_address}, @code{no_address_safety_analysis},
@code{no_sanitize_undefined},
@code{no_sanitize_undefined}, @code{bnd_legacy},
@code{error} and @code{warning}.
Several other attributes are defined for functions on particular
target systems. Other attributes, including @code{section} are
@ -3549,6 +3549,12 @@ The @code{no_sanitize_undefined} attribute on functions is used
to inform the compiler that it should not check for undefined behavior
in the function when compiling with the @option{-fsanitize=undefined} option.
@item bnd_legacy
@cindex @code{bnd_legacy} function attribute
The @code{bnd_legacy} attribute on functions is used to inform
compiler that function should not be instrumented when compiled
with @option{-fcheck-pointers} option.
@item regparm (@var{number})
@cindex @code{regparm} attribute
@cindex functions that are passed arguments in registers on the 386
@ -5321,12 +5327,12 @@ placed in either the @code{.bss_below100} section or the
The keyword @code{__attribute__} allows you to specify special
attributes of @code{struct} and @code{union} types when you define
such types. This keyword is followed by an attribute specification
inside double parentheses. Seven attributes are currently defined for
inside double parentheses. Eight attributes are currently defined for
types: @code{aligned}, @code{packed}, @code{transparent_union},
@code{unused}, @code{deprecated}, @code{visibility}, and
@code{may_alias}. Other attributes are defined for functions
(@pxref{Function Attributes}) and for variables (@pxref{Variable
Attributes}).
@code{unused}, @code{deprecated}, @code{visibility}, @code{may_alias}
and @code{bnd_variable_size}. Other attributes are defined for
functions (@pxref{Function Attributes}) and for variables
(@pxref{Variable Attributes}).
You may also specify any one of these attributes with @samp{__}
preceding and following its keyword. This allows you to use these
@ -5618,6 +5624,35 @@ and caught in another, the class must have default visibility.
Otherwise the two shared objects are unable to use the same
typeinfo node and exception handling will break.
@item bnd_variable_size
When applied to a structure field, this attribute tells Pointer
Bounds Checker that the size of this field should not be computed
using static type information. It may be used to mark variable
sized static array fields placed at the end of a structure.
@smallexample
struct S
@{
int size;
char data[1];
@}
S *p = (S *)malloc (sizeof(S) + 100);
p->data[10] = 0; //Bounds violation
@end smallexample
By using an attribute for a field we may avoid bound violation
we most probably do not want to see:
@smallexample
struct S
@{
int size;
char data[1] __attribute__((bnd_variable_size));
@}
S *p = (S *)malloc (sizeof(S) + 100);
p->data[10] = 0; //OK
@end smallexample
@end table
To specify multiple attributes, separate them by commas within the