Use array_at_struct_end_p to determine whether the trailing array of a structure is flexible array member in __builtin_object_size.
gcc/ChangeLog: PR tree-optimization/101836 * tree-object-size.cc (addr_object_size): Use array_at_struct_end_p to determine a flexible array member reference. gcc/testsuite/ChangeLog: PR tree-optimization/101836 * gcc.dg/pr101836.c: New test. * gcc.dg/pr101836_1.c: New test. * gcc.dg/pr101836_2.c: New test. * gcc.dg/pr101836_3.c: New test. * gcc.dg/pr101836_4.c: New test. * gcc.dg/pr101836_5.c: New test. * gcc.dg/strict-flex-array-2.c: New test. * gcc.dg/strict-flex-array-3.c: New test. --- gcc/testsuite/gcc.dg/pr101836.c | 60 ++++++++++++++++++++++ gcc/testsuite/gcc.dg/pr101836_1.c | 60 ++++++++++++++++++++++ gcc/testsuite/gcc.dg/pr101836_2.c | 60 ++++++++++++++++++++++ gcc/testsuite/gcc.dg/pr101836_3.c | 60 ++++++++++++++++++++++ gcc/testsuite/gcc.dg/pr101836_4.c | 60 ++++++++++++++++++++++ gcc/testsuite/gcc.dg/pr101836_5.c | 60 ++++++++++++++++++++++ gcc/testsuite/gcc.dg/strict-flex-array-2.c | 60 ++++++++++++++++++++++ gcc/testsuite/gcc.dg/strict-flex-array-3.c | 60 ++++++++++++++++++++++ gcc/tree-object-size.cc | 16 +++--- 9 files changed, 487 insertions(+), 9 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/pr101836.c create mode 100644 gcc/testsuite/gcc.dg/pr101836_1.c create mode 100644 gcc/testsuite/gcc.dg/pr101836_2.c create mode 100644 gcc/testsuite/gcc.dg/pr101836_3.c create mode 100644 gcc/testsuite/gcc.dg/pr101836_4.c create mode 100644 gcc/testsuite/gcc.dg/pr101836_5.c create mode 100644 gcc/testsuite/gcc.dg/strict-flex-array-2.c create mode 100644 gcc/testsuite/gcc.dg/strict-flex-array-3.c diff --git a/gcc/testsuite/gcc.dg/pr101836.c b/gcc/testsuite/gcc.dg/pr101836.c new file mode 100644 index 00000000000..efad02cfe89 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr101836.c @@ -0,0 +1,60 @@ +/* -fstrict-flex-arrays is aliased with -ftrict-flex-arrays=3, which is the + strictest, only [] is treated as flexible array. */ +/* PR tree-optimization/101836 */ +/* { dg-do run } */ +/* { dg-options "-O2 -fstrict-flex-arrays" } */ + +#include <stdio.h> + +#define expect(p, _v) do { \ + size_t v = _v; \ + if (p == v) \ + printf("ok: %s == %zd\n", #p, p); \ + else \ + { \ + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \ + __builtin_abort (); \ + } \ +} while (0); + +struct trailing_array_1 { + int a; + int b; + int c[4]; +}; + +struct trailing_array_2 { + int a; + int b; + int c[1]; +}; + +struct trailing_array_3 { + int a; + int b; + int c[0]; +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + expect(__builtin_object_size(normal->c, 1), 16); + expect(__builtin_object_size(trailing_1->c, 1), 4); + expect(__builtin_object_size(trailing_0->c, 1), 0); + expect(__builtin_object_size(trailing_flex->c, 1), -1); +} + +int main(int argc, char *argv[]) +{ + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void *)argv[0]); + + return 0; +} diff --git a/gcc/testsuite/gcc.dg/pr101836_1.c b/gcc/testsuite/gcc.dg/pr101836_1.c new file mode 100644 index 00000000000..e2931ce1012 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr101836_1.c @@ -0,0 +1,60 @@ +/* -fstrict-flex-arrays=3 is the strictest, only [] is treated as + flexible array. */ +/* PR tree-optimization/101836 */ +/* { dg-do run } */ +/* { dg-options "-O2 -fstrict-flex-arrays=3" } */ + +#include <stdio.h> + +#define expect(p, _v) do { \ + size_t v = _v; \ + if (p == v) \ + printf("ok: %s == %zd\n", #p, p); \ + else \ + { \ + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \ + __builtin_abort (); \ + } \ +} while (0); + +struct trailing_array_1 { + int a; + int b; + int c[4]; +}; + +struct trailing_array_2 { + int a; + int b; + int c[1]; +}; + +struct trailing_array_3 { + int a; + int b; + int c[0]; +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + expect(__builtin_object_size(normal->c, 1), 16); + expect(__builtin_object_size(trailing_1->c, 1), 4); + expect(__builtin_object_size(trailing_0->c, 1), 0); + expect(__builtin_object_size(trailing_flex->c, 1), -1); +} + +int main(int argc, char *argv[]) +{ + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void *)argv[0]); + + return 0; +} diff --git a/gcc/testsuite/gcc.dg/pr101836_2.c b/gcc/testsuite/gcc.dg/pr101836_2.c new file mode 100644 index 00000000000..78974187721 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr101836_2.c @@ -0,0 +1,60 @@ +/* When -fstrict-flex-arrays=2, only [] and [0] are treated as flexiable + arrays. */ +/* PR tree-optimization/101836 */ +/* { dg-do run } */ +/* { dg-options "-O2 -fstrict-flex-arrays=2" } */ + +#include <stdio.h> + +#define expect(p, _v) do { \ + size_t v = _v; \ + if (p == v) \ + printf("ok: %s == %zd\n", #p, p); \ + else \ + { \ + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \ + __builtin_abort (); \ + } \ +} while (0); + +struct trailing_array_1 { + int a; + int b; + int c[4]; +}; + +struct trailing_array_2 { + int a; + int b; + int c[1]; +}; + +struct trailing_array_3 { + int a; + int b; + int c[0]; +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + expect(__builtin_object_size(normal->c, 1), 16); + expect(__builtin_object_size(trailing_1->c, 1), 4); + expect(__builtin_object_size(trailing_0->c, 1), -1); + expect(__builtin_object_size(trailing_flex->c, 1), -1); +} + +int main(int argc, char *argv[]) +{ + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void *)argv[0]); + + return 0; +} diff --git a/gcc/testsuite/gcc.dg/pr101836_3.c b/gcc/testsuite/gcc.dg/pr101836_3.c new file mode 100644 index 00000000000..0e69388e81f --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr101836_3.c @@ -0,0 +1,60 @@ +/* When -fstrict-flex-arrays=1, [], [0], and [1] are treated as flexible + arrays. */ +/* PR tree-optimization/101836 */ +/* { dg-do run } */ +/* { dg-options "-O2 -fstrict-flex-arrays=1" } */ + +#include <stdio.h> + +#define expect(p, _v) do { \ + size_t v = _v; \ + if (p == v) \ + printf("ok: %s == %zd\n", #p, p); \ + else \ + { \ + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \ + __builtin_abort (); \ + } \ +} while (0); + +struct trailing_array_1 { + int a; + int b; + int c[4]; +}; + +struct trailing_array_2 { + int a; + int b; + int c[1]; +}; + +struct trailing_array_3 { + int a; + int b; + int c[0]; +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + expect(__builtin_object_size(normal->c, 1), 16); + expect(__builtin_object_size(trailing_1->c, 1), -1); + expect(__builtin_object_size(trailing_0->c, 1), -1); + expect(__builtin_object_size(trailing_flex->c, 1), -1); +} + +int main(int argc, char *argv[]) +{ + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void *)argv[0]); + + return 0; +} diff --git a/gcc/testsuite/gcc.dg/pr101836_4.c b/gcc/testsuite/gcc.dg/pr101836_4.c new file mode 100644 index 00000000000..e0025aa9a7b --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr101836_4.c @@ -0,0 +1,60 @@ +/* when -fstrict-flex-arrays=0, all trailing arrays are treated as + flexible arrays. */ +/* PR tree-optimization/101836 */ +/* { dg-do run } */ +/* { dg-options "-O2 -fstrict-flex-arrays=0" } */ + +#include <stdio.h> + +#define expect(p, _v) do { \ + size_t v = _v; \ + if (p == v) \ + printf("ok: %s == %zd\n", #p, p); \ + else \ + { \ + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \ + __builtin_abort (); \ + } \ +} while (0); + +struct trailing_array_1 { + int a; + int b; + int c[4]; +}; + +struct trailing_array_2 { + int a; + int b; + int c[1]; +}; + +struct trailing_array_3 { + int a; + int b; + int c[0]; +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + expect(__builtin_object_size(normal->c, 1), -1); + expect(__builtin_object_size(trailing_1->c, 1), -1); + expect(__builtin_object_size(trailing_0->c, 1), -1); + expect(__builtin_object_size(trailing_flex->c, 1), -1); +} + +int main(int argc, char *argv[]) +{ + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void *)argv[0]); + + return 0; +} diff --git a/gcc/testsuite/gcc.dg/pr101836_5.c b/gcc/testsuite/gcc.dg/pr101836_5.c new file mode 100644 index 00000000000..0ad8bbf693c --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr101836_5.c @@ -0,0 +1,60 @@ +/* -fno-strict-flex-arrays is aliased to -fstrict-flex-arrays=0, + all trailing arrays are treated as flexible array. */ +/* PR tree-optimization/101836 */ +/* { dg-do run } */ +/* { dg-options "-O2 -fno-strict-flex-arrays" } */ + +#include <stdio.h> + +#define expect(p, _v) do { \ + size_t v = _v; \ + if (p == v) \ + printf("ok: %s == %zd\n", #p, p); \ + else \ + { \ + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \ + __builtin_abort (); \ + } \ +} while (0); + +struct trailing_array_1 { + int a; + int b; + int c[4]; +}; + +struct trailing_array_2 { + int a; + int b; + int c[1]; +}; + +struct trailing_array_3 { + int a; + int b; + int c[0]; +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + expect(__builtin_object_size(normal->c, 1), -1); + expect(__builtin_object_size(trailing_1->c, 1), -1); + expect(__builtin_object_size(trailing_0->c, 1), -1); + expect(__builtin_object_size(trailing_flex->c, 1), -1); +} + +int main(int argc, char *argv[]) +{ + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void *)argv[0]); + + return 0; +} diff --git a/gcc/testsuite/gcc.dg/strict-flex-array-2.c b/gcc/testsuite/gcc.dg/strict-flex-array-2.c new file mode 100644 index 00000000000..2b80c2365f3 --- /dev/null +++ b/gcc/testsuite/gcc.dg/strict-flex-array-2.c @@ -0,0 +1,60 @@ +/* test the combination of attribute strict_flex_array and option + -fstrict-flex-arrays: when both attribute and option specified, + attribute will have higher priority. */ +/* { dg-do run } */ +/* { dg-options "-O2 -fstrict-flex-arrays=3" } */ + +#include <stdio.h> + +#define expect(p, _v) do { \ + size_t v = _v; \ + if (p == v) \ + printf("ok: %s == %zd\n", #p, p); \ + else \ + { \ + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \ + __builtin_abort (); \ + } \ +} while (0); + +struct trailing_array_1 { + int a; + int b; + int c[4] __attribute__ ((strict_flex_array (0))); +}; + +struct trailing_array_2 { + int a; + int b; + int c[1] __attribute__ ((strict_flex_array (1))); +}; + +struct trailing_array_3 { + int a; + int b; + int c[0] __attribute__ ((strict_flex_array (2))); +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + expect(__builtin_object_size(normal->c, 1), -1); + expect(__builtin_object_size(trailing_1->c, 1), -1); + expect(__builtin_object_size(trailing_0->c, 1), -1); + expect(__builtin_object_size(trailing_flex->c, 1), -1); +} + +int main(int argc, char *argv[]) +{ + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void *)argv[0]); + + return 0; +} diff --git a/gcc/testsuite/gcc.dg/strict-flex-array-3.c b/gcc/testsuite/gcc.dg/strict-flex-array-3.c new file mode 100644 index 00000000000..602f99dc79a --- /dev/null +++ b/gcc/testsuite/gcc.dg/strict-flex-array-3.c @@ -0,0 +1,60 @@ +/* test the combination of attribute strict_flex_array and option + -fstrict-flex-arrays: when both attribute and option specified, + attribute will have higher priority. */ +/* { dg-do run } */ +/* { dg-options "-O2 -fstrict-flex-arrays=0" } */ + +#include <stdio.h> + +#define expect(p, _v) do { \ + size_t v = _v; \ + if (p == v) \ + printf("ok: %s == %zd\n", #p, p); \ + else \ + { \ + printf("WAT: %s == %zd (expected %zd)\n", #p, p, v); \ + __builtin_abort (); \ + } \ +} while (0); + +struct trailing_array_1 { + int a; + int b; + int c[4] __attribute__ ((strict_flex_array (1))); +}; + +struct trailing_array_2 { + int a; + int b; + int c[1] __attribute__ ((strict_flex_array (2))); +}; + +struct trailing_array_3 { + int a; + int b; + int c[0] __attribute__ ((strict_flex_array (3))); +}; +struct trailing_array_4 { + int a; + int b; + int c[]; +}; + +void __attribute__((__noinline__)) stuff( + struct trailing_array_1 *normal, + struct trailing_array_2 *trailing_1, + struct trailing_array_3 *trailing_0, + struct trailing_array_4 *trailing_flex) +{ + expect(__builtin_object_size(normal->c, 1), 16); + expect(__builtin_object_size(trailing_1->c, 1), 4); + expect(__builtin_object_size(trailing_0->c, 1), 0); + expect(__builtin_object_size(trailing_flex->c, 1), -1); +} + +int main(int argc, char *argv[]) +{ + stuff((void *)argv[0], (void *)argv[0], (void *)argv[0], (void *)argv[0]); + + return 0; +} diff --git a/gcc/tree-object-size.cc b/gcc/tree-object-size.cc index 4eb454a4a33..1f04cb80fd0 100644 --- a/gcc/tree-object-size.cc +++ b/gcc/tree-object-size.cc @@ -604,9 +604,9 @@ addr_object_size (struct object_size_info *osi, const_tree ptr, else if (var != pt_var && TREE_CODE (pt_var) == MEM_REF) { tree v = var; - /* For &X->fld, compute object size only if fld isn't the last - field, as struct { int i; char c[1]; } is often used instead - of flexible array member. */ + /* For &X->fld, compute object size if fld isn't a flexible array + member. */ + bool is_flexible_array_mem_ref = false; while (v && v != pt_var) switch (TREE_CODE (v)) { @@ -633,6 +633,7 @@ addr_object_size (struct object_size_info *osi, const_tree ptr, v = NULL_TREE; break; } + is_flexible_array_mem_ref = array_at_struct_end_p (v); while (v != pt_var && TREE_CODE (v) == COMPONENT_REF) if (TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0))) != UNION_TYPE @@ -645,12 +646,9 @@ addr_object_size (struct object_size_info *osi, const_tree ptr, && TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0))) == RECORD_TYPE) { - tree fld_chain = DECL_CHAIN (TREE_OPERAND (v, 1)); - for (; fld_chain; fld_chain = DECL_CHAIN (fld_chain)) - if (TREE_CODE (fld_chain) == FIELD_DECL) - break; - - if (fld_chain) + /* compute object size only if v is not a + flexible array member. */ + if (!is_flexible_array_mem_ref) { v = NULL_TREE; break; -- 2.31.1