re PR c/67882 (surprising offsetof result on an invalid array member without diagnostic)
PR c++-common/67882
* c-family/c-common.h (fold_offsetof_1): Add argument.
* c-family/c-common.c (fold_offsetof_1): Diagnose more invalid
offsetof expressions that reference elements past the end of
an array.
* c-c++-common/builtin-offsetof-2.c: New test.
From-SVN: r229717
This commit is contained in:
Martin Sebor
parent
aa3d33850f
commit
c85158dec6
|
|
@ -1,3 +1,11 @@
|
|||
2015-11-03 Bernd Schmidt <bschmidt@redhat.com>
|
||||
|
||||
PR c++-common/67882
|
||||
* c-family/c-common.h (fold_offsetof_1): Add argument.
|
||||
* c-family/c-common.c (fold_offsetof_1): Diagnose more invalid
|
||||
offsetof expressions that reference elements past the end of
|
||||
an array.
|
||||
|
||||
2015-11-03 Thomas Schwinge <thomas@codesourcery.com>
|
||||
Chung-Lin Tang <cltang@codesourcery.com>
|
||||
|
||||
|
|
|
|||
|
|
@ -10631,11 +10631,11 @@ c_common_to_target_charset (HOST_WIDE_INT c)
|
|||
traditional rendering of offsetof as a macro. Return the folded result. */
|
||||
|
||||
tree
|
||||
fold_offsetof_1 (tree expr)
|
||||
fold_offsetof_1 (tree expr, enum tree_code ctx)
|
||||
{
|
||||
tree base, off, t;
|
||||
|
||||
switch (TREE_CODE (expr))
|
||||
tree_code code = TREE_CODE (expr);
|
||||
switch (code)
|
||||
{
|
||||
case ERROR_MARK:
|
||||
return expr;
|
||||
|
|
@ -10659,7 +10659,7 @@ fold_offsetof_1 (tree expr)
|
|||
return TREE_OPERAND (expr, 0);
|
||||
|
||||
case COMPONENT_REF:
|
||||
base = fold_offsetof_1 (TREE_OPERAND (expr, 0));
|
||||
base = fold_offsetof_1 (TREE_OPERAND (expr, 0), code);
|
||||
if (base == error_mark_node)
|
||||
return base;
|
||||
|
||||
|
|
@ -10676,7 +10676,7 @@ fold_offsetof_1 (tree expr)
|
|||
break;
|
||||
|
||||
case ARRAY_REF:
|
||||
base = fold_offsetof_1 (TREE_OPERAND (expr, 0));
|
||||
base = fold_offsetof_1 (TREE_OPERAND (expr, 0), code);
|
||||
if (base == error_mark_node)
|
||||
return base;
|
||||
|
||||
|
|
@ -10691,8 +10691,9 @@ fold_offsetof_1 (tree expr)
|
|||
&& !tree_int_cst_equal (upbound,
|
||||
TYPE_MAX_VALUE (TREE_TYPE (upbound))))
|
||||
{
|
||||
upbound = size_binop (PLUS_EXPR, upbound,
|
||||
build_int_cst (TREE_TYPE (upbound), 1));
|
||||
if (ctx != ARRAY_REF && ctx != COMPONENT_REF)
|
||||
upbound = size_binop (PLUS_EXPR, upbound,
|
||||
build_int_cst (TREE_TYPE (upbound), 1));
|
||||
if (tree_int_cst_lt (upbound, t))
|
||||
{
|
||||
tree v;
|
||||
|
|
|
|||
|
|
@ -1029,7 +1029,7 @@ extern bool c_dump_tree (void *, tree);
|
|||
|
||||
extern void verify_sequence_points (tree);
|
||||
|
||||
extern tree fold_offsetof_1 (tree);
|
||||
extern tree fold_offsetof_1 (tree, tree_code ctx = ERROR_MARK);
|
||||
extern tree fold_offsetof (tree);
|
||||
|
||||
/* Places where an lvalue, or modifiable lvalue, may be required.
|
||||
|
|
|
|||
|
|
@ -1,3 +1,8 @@
|
|||
2015-11-03 Martin Sebor <msebor@redhat.com>
|
||||
|
||||
PR c++-common/67882
|
||||
* c-c++-common/builtin-offsetof-2.c: New test.
|
||||
|
||||
2015-11-03 Dominique d'Humieres <dominiq@lps.ens.fr>
|
||||
|
||||
PR fortran/67982
|
||||
|
|
|
|||
|
|
@ -0,0 +1,217 @@
|
|||
// { dg-options "-Warray-bounds" }
|
||||
// { dg-do compile }
|
||||
|
||||
// Test case exercising pr c/67882 - surprising offsetof result
|
||||
// on an invalid array member without diagnostic.
|
||||
|
||||
typedef struct A1 {
|
||||
char a1[1];
|
||||
char c;
|
||||
} A1;
|
||||
|
||||
typedef struct A1_x_2 {
|
||||
char a1[1];
|
||||
char a[][2];
|
||||
} A1_x_2;
|
||||
|
||||
typedef struct A1_1_x {
|
||||
char a1_1[1][1];
|
||||
char a[];
|
||||
} A1_1_x;
|
||||
|
||||
typedef struct Ax_2_3 {
|
||||
int i;
|
||||
char a_x_2_3[][2][3];
|
||||
} Ax_2_3;
|
||||
|
||||
typedef struct A1_1 {
|
||||
char a1_1[1][1];
|
||||
char c;
|
||||
} A1_1;
|
||||
|
||||
typedef struct B {
|
||||
A1_1 a2_3[2][3];
|
||||
char a1_1[3][5];
|
||||
char a[];
|
||||
} B;
|
||||
|
||||
// Structures with members that contain flexible array members are
|
||||
// an extension accepted by GCC.
|
||||
typedef struct C {
|
||||
A1_1_x a5_7 [5][7];
|
||||
int a;
|
||||
} C;
|
||||
|
||||
// Structs with a "fake" flexible array member (a GCC extension).
|
||||
typedef struct FA0 {
|
||||
int i;
|
||||
char a0 [0];
|
||||
} FA0;
|
||||
|
||||
typedef struct FA1 {
|
||||
int i;
|
||||
char a1 [1];
|
||||
} FA1;
|
||||
|
||||
typedef struct FA3 {
|
||||
int i;
|
||||
char a3 [3];
|
||||
} FA3;
|
||||
|
||||
// A "fake" multidimensional flexible array member.
|
||||
typedef struct FA5_7 {
|
||||
int i;
|
||||
char a5_7 [5][7];
|
||||
} FA5_7;
|
||||
|
||||
static void test (void)
|
||||
{
|
||||
// Verify that offsetof references to array elements past the end of
|
||||
// the array member are diagnosed. As an extension, permit references
|
||||
// to the element just past-the-end of the array.
|
||||
|
||||
int a[] = {
|
||||
__builtin_offsetof (A1, a1), // valid
|
||||
__builtin_offsetof (A1, a1 [0]), // valid
|
||||
|
||||
// The following expression is valid because it forms the equivalent
|
||||
// of an address pointing just past the last element of the array.
|
||||
__builtin_offsetof (A1, a1 [1]), // valid
|
||||
|
||||
__builtin_offsetof (A1, a1 [2]), // { dg-warning "index" }
|
||||
|
||||
__builtin_offsetof (A1_x_2, a1), // valid
|
||||
__builtin_offsetof (A1_x_2, a1 [0]), // valid
|
||||
__builtin_offsetof (A1_x_2, a1 [1]), // valid
|
||||
__builtin_offsetof (A1_x_2, a1 [2]), // { dg-warning "index" }
|
||||
|
||||
__builtin_offsetof (A1_x_2, a), // valid
|
||||
__builtin_offsetof (A1_x_2, a [0]), // valid
|
||||
__builtin_offsetof (A1_x_2, a [1]), // valid
|
||||
__builtin_offsetof (A1_x_2, a [99]), // valid
|
||||
|
||||
__builtin_offsetof (A1_x_2, a), // valid
|
||||
__builtin_offsetof (A1_x_2, a [0][0]), // valid
|
||||
__builtin_offsetof (A1_x_2, a [0][1]), // valid
|
||||
|
||||
// The following expression is valid because it forms the equivalent
|
||||
// of an address pointing just past the last element of the first
|
||||
// array.
|
||||
__builtin_offsetof (A1_x_2, a [0][2]), // valid
|
||||
|
||||
// Unlike the case above, this is invalid since it refers to an element
|
||||
// past one one just-past-the-end in A[][2].
|
||||
__builtin_offsetof (A1_x_2, a [0][3]), // { dg-warning "index" }
|
||||
|
||||
__builtin_offsetof (A1_x_2, a [1][0]), // valid
|
||||
__builtin_offsetof (A1_x_2, a [1][1]), // valid
|
||||
__builtin_offsetof (A1_x_2, a [1][2]), // valid
|
||||
__builtin_offsetof (A1_x_2, a [99][0]), // valid
|
||||
__builtin_offsetof (A1_x_2, a [99][1]), // valid
|
||||
__builtin_offsetof (A1_x_2, a [99][2]), // valid
|
||||
|
||||
__builtin_offsetof (A1_1_x, a), // valid
|
||||
__builtin_offsetof (A1_1_x, a [0]), // valid
|
||||
__builtin_offsetof (A1_1_x, a [1]), // valid
|
||||
__builtin_offsetof (A1_1_x, a [99]), // valid
|
||||
|
||||
__builtin_offsetof (A1_1_x, a1_1 [0][0]), // valid
|
||||
__builtin_offsetof (A1_1_x, a1_1 [0][1]), // valid
|
||||
__builtin_offsetof (A1_1_x, a1_1 [0][2]), // { dg-warning "index" }
|
||||
__builtin_offsetof (A1_1_x, a1_1 [1][0]), // { dg-warning "index" }
|
||||
__builtin_offsetof (A1_1_x, a1_1 [1][1]), // { dg-warning "index" }
|
||||
|
||||
__builtin_offsetof (Ax_2_3, a_x_2_3 [0][1][3]), // valid
|
||||
__builtin_offsetof (Ax_2_3, a_x_2_3 [0][1][4]), // { dg-warning "index" }
|
||||
__builtin_offsetof (Ax_2_3, a_x_2_3 [0][2]), // valid
|
||||
__builtin_offsetof (Ax_2_3, a_x_2_3 [0][2][0]), // { dg-warning "index" }
|
||||
|
||||
__builtin_offsetof (B, a2_3 [0][0].c), // valid
|
||||
__builtin_offsetof (B, a2_3 [0][0].a1_1 [0][0]), // valid
|
||||
__builtin_offsetof (B, a2_3 [1][3]), // valid
|
||||
__builtin_offsetof (B, a2_3 [1][4]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [0][0].a1_1 [0][1]), // valid
|
||||
__builtin_offsetof (B, a2_3 [0][0].a1_1 [0][2]), // { dg-warning "index" }
|
||||
|
||||
__builtin_offsetof (B, a2_3 [0][0].a1_1 [1][0]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [0][0].a1_1 [1][1]), // { dg-warning "index" }
|
||||
|
||||
__builtin_offsetof (B, a2_3 [1][2].a1_1 [0][0]), // valid
|
||||
|
||||
// Forming an offset to the just-past-end element is valid.
|
||||
__builtin_offsetof (B, a2_3 [1][2].a1_1 [0][1]), // valid
|
||||
__builtin_offsetof (B, a2_3 [1][2].a1_1 [1][0]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [1][2].a1_1 [1][1]), // { dg-warning "index" }
|
||||
|
||||
// Forming an offset to the just-past-end element is valid.
|
||||
__builtin_offsetof (B, a2_3 [1][3]), // valid
|
||||
// ...but these are diagnosed because they dereference a just-past-the-end
|
||||
// element.
|
||||
__builtin_offsetof (B, a2_3 [1][3].a1_1 [0][0]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [1][3].a1_1 [0][0]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [1][3].a1_1 [0][1]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [1][3].a1_1 [1][0]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [1][3].a1_1 [1][1]), // { dg-warning "index" }
|
||||
|
||||
// Analogous to the case above, these are both diagnosed because they
|
||||
// dereference just-past-the-end elements of the a2_3 array.
|
||||
__builtin_offsetof (B, a2_3 [1][3].c), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [1][3].c), // { dg-warning "index" }
|
||||
|
||||
// The following are all invalid because of the reference to a2_3[2].
|
||||
__builtin_offsetof (B, a2_3 [2][0].a1_1 [0][0]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [2][0].a1_1 [0][1]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [2][0].a1_1 [1][0]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [2][0].a1_1 [1][1]), // { dg-warning "index" }
|
||||
__builtin_offsetof (B, a2_3 [2][0].c), // { dg-warning "index" }
|
||||
|
||||
__builtin_offsetof (C, a5_7 [4][6]),
|
||||
__builtin_offsetof (C, a5_7 [4][6].a),
|
||||
__builtin_offsetof (C, a5_7 [4][6].a [0]),
|
||||
__builtin_offsetof (C, a5_7 [4][6].a [99]),
|
||||
|
||||
__builtin_offsetof (C, a5_7 [4][7]), // valid
|
||||
// Diagnose the following even though the object whose offset is
|
||||
// computed is a flexible array member.
|
||||
__builtin_offsetof (C, a5_7 [4][7].a), // { dg-warning "index" }
|
||||
__builtin_offsetof (C, a5_7 [4][7].a [0]), // { dg-warning "index" }
|
||||
__builtin_offsetof (C, a5_7 [4][7].a [99]), // { dg-warning "index" }
|
||||
|
||||
// Verify that no diagnostic is issued for offsetof expressions
|
||||
// involving structs where the array has a rank of 1 and is the last
|
||||
// member (e.g., those are treated as flexible array members).
|
||||
__builtin_offsetof (FA0, a0 [0]),
|
||||
__builtin_offsetof (FA0, a0 [1]),
|
||||
__builtin_offsetof (FA0, a0 [99]),
|
||||
|
||||
__builtin_offsetof (FA1, a1 [0]),
|
||||
__builtin_offsetof (FA1, a1 [1]),
|
||||
__builtin_offsetof (FA1, a1 [99]),
|
||||
|
||||
__builtin_offsetof (FA3, a3 [0]),
|
||||
__builtin_offsetof (FA3, a3 [3]),
|
||||
__builtin_offsetof (FA3, a3 [99]),
|
||||
|
||||
__builtin_offsetof (FA5_7, a5_7 [0][0]),
|
||||
|
||||
// Unlike one-dimensional arrays, verify that out-of-bounds references
|
||||
// to "fake" flexible arrays with rank of 2 and greater are diagnosed.
|
||||
|
||||
// The following are valid because they compute the offset of just past
|
||||
// the end of each of the a5_7[0] and a5_7[1] arrays.
|
||||
__builtin_offsetof (FA5_7, a5_7 [0][7]), // valid
|
||||
__builtin_offsetof (FA5_7, a5_7 [1][7]), // valid
|
||||
|
||||
// The following two are accepted as an extesion (because a5_7 is
|
||||
// treated as a flexible array member).
|
||||
__builtin_offsetof (FA5_7, a5_7 [5][0]), // extension
|
||||
__builtin_offsetof (FA5_7, a5_7 [5][7]), // extension
|
||||
|
||||
// The following are invalid since in both cases they denote an element
|
||||
// that's beyond just-past-the-end of the array.
|
||||
__builtin_offsetof (FA5_7, a5_7 [0][8]), // { dg-warning "index" }
|
||||
__builtin_offsetof (FA5_7, a5_7 [6][8]) // { dg-warning "index" }
|
||||
};
|
||||
|
||||
(void)&a;
|
||||
}
|
||||
Loading…
Reference in New Issue