From d32599a6e99da9345d2b7d94834b7e9dfcc109a8 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Fri, 6 Nov 2009 09:46:45 +0100 Subject: [PATCH] re PR c/41935 (ICE : tree check: expected integer_cst, have nop_expr in int_cst_value, at tree.c:8301) PR middle-end/41935 * c-common.c (fold_offsetof_1) : Don't crash for VLAs or non-constant index, allow index one past the last element and allow exceeding array bound in arrays that might be used as flexible array members. * gcc.dg/pr41935.c: New test. * c-c++-common/pr41935.c: New test. * c-c++-common/builtin-offsetof.c (f0): Allow index one past the last element. * gcc.c-torture/execute/pr41935.c: New test. From-SVN: r153962 --- gcc/ChangeLog | 8 +++ gcc/c-common.c | 48 ++++++++++--- gcc/testsuite/ChangeLog | 9 +++ gcc/testsuite/c-c++-common/builtin-offsetof.c | 4 +- gcc/testsuite/c-c++-common/pr41935.c | 70 +++++++++++++++++++ gcc/testsuite/gcc.c-torture/execute/pr41935.c | 25 +++++++ gcc/testsuite/gcc.dg/pr41935.c | 25 +++++++ 7 files changed, 179 insertions(+), 10 deletions(-) create mode 100644 gcc/testsuite/c-c++-common/pr41935.c create mode 100644 gcc/testsuite/gcc.c-torture/execute/pr41935.c create mode 100644 gcc/testsuite/gcc.dg/pr41935.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index a39ecba33d7..70ed436e13a 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2009-11-06 Jakub Jelinek + + PR middle-end/41935 + * c-common.c (fold_offsetof_1) : Don't crash for VLAs + or non-constant index, allow index one past the last element and + allow exceeding array bound in arrays that might be used as flexible + array members. + 2009-11-05 Richard Henderson * config/i386/ia32intrin.h: Protect CRC32 builtins with __SSE4_2__. diff --git a/gcc/c-common.c b/gcc/c-common.c index a9ca9608db1..20b24f0c3c2 100644 --- a/gcc/c-common.c +++ b/gcc/c-common.c @@ -8398,14 +8398,46 @@ fold_offsetof_1 (tree expr, tree stop_ref) off = size_binop (MULT_EXPR, TYPE_SIZE_UNIT (TREE_TYPE (expr)), t); /* Check if the offset goes beyond the upper bound of the array. */ - { - tree nelts = array_type_nelts (TREE_TYPE (TREE_OPERAND (expr, 0))); - HOST_WIDE_INT index = int_cst_value (t); - if (index > int_cst_value (nelts)) - warning (OPT_Warray_bounds, - "index %wd denotes an offset greater than size of %qT", - index, TREE_TYPE (TREE_OPERAND (expr, 0))); - } + if (code == PLUS_EXPR && TREE_CODE (t) == INTEGER_CST) + { + tree upbound = array_ref_up_bound (expr); + if (upbound != NULL_TREE + && TREE_CODE (upbound) == INTEGER_CST + && !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 (tree_int_cst_lt (upbound, t)) + { + tree v; + + for (v = TREE_OPERAND (expr, 0); + TREE_CODE (v) == COMPONENT_REF; + v = TREE_OPERAND (v, 0)) + if (TREE_CODE (TREE_TYPE (TREE_OPERAND (v, 0))) + == RECORD_TYPE) + { + tree fld_chain = TREE_CHAIN (TREE_OPERAND (v, 1)); + for (; fld_chain; fld_chain = TREE_CHAIN (fld_chain)) + if (TREE_CODE (fld_chain) == FIELD_DECL) + break; + + if (fld_chain) + break; + } + /* Don't warn if the array might be considered a poor + man's flexible array member with a very permissive + definition thereof. */ + if (TREE_CODE (v) == ARRAY_REF + || TREE_CODE (v) == COMPONENT_REF) + warning (OPT_Warray_bounds, + "index %E denotes an offset " + "greater than size of %qT", + t, TREE_TYPE (TREE_OPERAND (expr, 0))); + } + } + } break; case COMPOUND_EXPR: diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 2aba6077d22..04ce93904a1 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,12 @@ +2009-11-06 Jakub Jelinek + + PR middle-end/41935 + * gcc.dg/pr41935.c: New test. + * c-c++-common/pr41935.c: New test. + * c-c++-common/builtin-offsetof.c (f0): Allow index one past the last + element. + * gcc.c-torture/execute/pr41935.c: New test. + 2009-11-05 Jason Merrill PR c++/34180 diff --git a/gcc/testsuite/c-c++-common/builtin-offsetof.c b/gcc/testsuite/c-c++-common/builtin-offsetof.c index 0ab498acd09..6d97775467d 100644 --- a/gcc/testsuite/c-c++-common/builtin-offsetof.c +++ b/gcc/testsuite/c-c++-common/builtin-offsetof.c @@ -21,9 +21,9 @@ f0 () __builtin_offsetof(struct A, p[0]); // { dg-error "non constant address" } __builtin_offsetof(struct B, p[0]); // OK __builtin_offsetof(struct B, p[9]); // OK - __builtin_offsetof(struct B, p[10]); // { dg-warning "greater than size" } + __builtin_offsetof(struct B, p[10]); // OK + __builtin_offsetof(struct B, p[11]); // { dg-warning "greater than size" } __builtin_offsetof(struct B, a.p); // OK __builtin_offsetof(struct B, p[0]); // OK __builtin_offsetof(struct B, a.p[0]); // { dg-error "non constant address" } } - diff --git a/gcc/testsuite/c-c++-common/pr41935.c b/gcc/testsuite/c-c++-common/pr41935.c new file mode 100644 index 00000000000..3279e75593d --- /dev/null +++ b/gcc/testsuite/c-c++-common/pr41935.c @@ -0,0 +1,70 @@ +/* { dg-options "-Warray-bounds" } */ +/* { dg-do compile } */ + +struct A +{ + int i; + char p[1]; +}; + +struct B +{ + struct A a; + int i; +}; + +struct C +{ + int i; + struct A a; +}; + +union D +{ + char p[1]; + struct A a; + struct B b; + struct C c; +}; + +struct E +{ + int i; + union D d; +}; + +struct F +{ + union D d; + int i; +}; + +union G +{ + int i; + union D d; +}; + +void +f0 () +{ + __builtin_offsetof (struct A, p[4]); /* OK */ + __builtin_offsetof (struct B, a.p[4]); /* { dg-warning "greater than size" } */ + __builtin_offsetof (struct C, a.p[4]); /* OK */ + __builtin_offsetof (union D, p[4]); /* OK */ + __builtin_offsetof (union D, a.p[4]); /* OK */ + __builtin_offsetof (union D, b.a.p[4]); /* { dg-warning "greater than size" } */ + __builtin_offsetof (union D, c.a.p[4]); /* OK */ + __builtin_offsetof (struct E, d.p[4]); /* OK */ + __builtin_offsetof (struct E, d.a.p[4]); /* OK */ + __builtin_offsetof (struct E, d.b.a.p[4]); /* { dg-warning "greater than size" } */ + __builtin_offsetof (struct E, d.c.a.p[4]); /* OK */ + __builtin_offsetof (struct F, d.p[4]); /* { dg-warning "greater than size" } */ + __builtin_offsetof (struct F, d.a.p[4]); /* { dg-warning "greater than size" } */ + __builtin_offsetof (struct F, d.b.a.p[4]); /* { dg-warning "greater than size" } */ + __builtin_offsetof (struct F, d.c.a.p[4]); /* { dg-warning "greater than size" } */ + __builtin_offsetof (union G, d.p[4]); /* OK */ + __builtin_offsetof (union G, d.a.p[4]); /* OK */ + __builtin_offsetof (union G, d.b.a.p[4]); /* { dg-warning "greater than size" } */ + __builtin_offsetof (union G, d.c.a.p[4]); /* OK */ +} diff --git a/gcc/testsuite/gcc.c-torture/execute/pr41935.c b/gcc/testsuite/gcc.c-torture/execute/pr41935.c new file mode 100644 index 00000000000..ef8d08ce023 --- /dev/null +++ b/gcc/testsuite/gcc.c-torture/execute/pr41935.c @@ -0,0 +1,25 @@ +/* PR middle-end/41935 */ + +extern void abort (void); + +long int +foo (int n, int i, int j) +{ + typedef int T[n]; + struct S { int a; T b[n]; }; + return __builtin_offsetof (struct S, b[i][j]); +} + +int +main (void) +{ + typedef int T[5]; + struct S { int a; T b[5]; }; + if (foo (5, 2, 3) + != __builtin_offsetof (struct S, b) + (5 * 2 + 3) * sizeof (int)) + abort (); + if (foo (5, 5, 5) + != __builtin_offsetof (struct S, b) + (5 * 5 + 5) * sizeof (int)) + abort (); + return 0; +} diff --git a/gcc/testsuite/gcc.dg/pr41935.c b/gcc/testsuite/gcc.dg/pr41935.c new file mode 100644 index 00000000000..e6a1b28670a --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr41935.c @@ -0,0 +1,25 @@ +/* PR middle-end/41935 */ +/* { dg-do run } */ +/* { dg-options "-O2" } */ + +extern void abort (void); +struct A { int a; int b[10]; }; + +int +foo (struct A *p) +{ + return __builtin_offsetof (struct A, b[p->a]); +} + +int +main () +{ + struct A a; + a.a = 7; + if (foo (&a) != 7 * sizeof (int) + __builtin_offsetof (struct A, b)) + abort (); + a.a = 2; + if (foo (&a) != 2 * sizeof (int) + __builtin_offsetof (struct A, b)) + abort (); + return 0; +}