Hi!
The following patch enables the -Walloc-size and -Wcalloc-transposed-args
warnings for C++ as well.
Ok for trunk if it passes bootstrap/regtest?
2023-12-20 Jakub Jelinek <ja...@redhat.com>
gcc/c-family/
* c.opt (Walloc-size): Enable also for C++ and ObjC++.
gcc/cp/
* cp-gimplify.cc (cp_genericize_r): If warn_alloc_size, call
warn_for_alloc_size for -Walloc-size diagnostics.
* semantics.cc (finish_call_expr): If warn_calloc_transposed_args,
call warn_for_calloc for -Wcalloc-transposed-args diagnostics.
gcc/testsuite/
* g++.dg/warn/Walloc-size-1.C: New test.
* g++.dg/warn/Wcalloc-transposed-args-1.C: New test.
--- gcc/c-family/c.opt.jj 2023-12-20 11:31:07.897806698 +0100
+++ gcc/c-family/c.opt 2023-12-20 20:02:36.889910599 +0100
@@ -332,7 +332,7 @@ C ObjC C++ ObjC++ Var(warn_alloca) Warni
Warn on any use of alloca.
Walloc-size
-C ObjC Var(warn_alloc_size) Warning LangEnabledBy(C ObjC, Wextra)
+C ObjC C++ ObjC++ Var(warn_alloc_size) Warning LangEnabledBy(C ObjC C++
ObjC++, Wextra)
Warn when allocating insufficient storage for the target type of the assigned
pointer.
Walloc-size-larger-than=
--- gcc/cp/cp-gimplify.cc.jj 2023-12-15 10:08:53.877236695 +0100
+++ gcc/cp/cp-gimplify.cc 2023-12-20 20:10:59.689914648 +0100
@@ -2048,6 +2048,25 @@ cp_genericize_r (tree *stmt_p, int *walk
case NOP_EXPR:
*stmt_p = predeclare_vla (*stmt_p);
+
+ /* Warn of new allocations that are not big enough for the target
+ type. */
+ if (warn_alloc_size
+ && TREE_CODE (TREE_OPERAND (stmt, 0)) == CALL_EXPR
+ && POINTER_TYPE_P (TREE_TYPE (stmt)))
+ {
+ if (tree fndecl = get_callee_fndecl (TREE_OPERAND (stmt, 0)))
+ if (DECL_IS_MALLOC (fndecl))
+ {
+ tree attrs = TYPE_ATTRIBUTES (TREE_TYPE (fndecl));
+ tree alloc_size = lookup_attribute ("alloc_size", attrs);
+ if (alloc_size)
+ warn_for_alloc_size (EXPR_LOCATION (stmt),
+ TREE_TYPE (TREE_TYPE (stmt)),
+ TREE_OPERAND (stmt, 0), alloc_size);
+ }
+ }
+
if (!wtd->no_sanitize_p
&& sanitize_flags_p (SANITIZE_NULL | SANITIZE_ALIGNMENT)
&& TYPE_REF_P (TREE_TYPE (stmt)))
--- gcc/cp/semantics.cc.jj 2023-12-14 07:49:53.150580801 +0100
+++ gcc/cp/semantics.cc 2023-12-20 20:13:33.773772759 +0100
@@ -2939,15 +2939,24 @@ finish_call_expr (tree fn, vec<tree, va_
if (!result)
{
- if (warn_sizeof_pointer_memaccess
+ tree alloc_size_attr = NULL_TREE;
+ if (warn_calloc_transposed_args
+ && TREE_CODE (fn) == FUNCTION_DECL
+ && (alloc_size_attr
+ = lookup_attribute ("alloc_size",
+ TYPE_ATTRIBUTES (TREE_TYPE (fn)))))
+ if (TREE_VALUE (alloc_size_attr) == NULL_TREE
+ || TREE_CHAIN (TREE_VALUE (alloc_size_attr)) == NULL_TREE)
+ alloc_size_attr = NULL_TREE;
+ if ((warn_sizeof_pointer_memaccess || alloc_size_attr)
&& (complain & tf_warning)
&& !vec_safe_is_empty (*args)
&& !processing_template_decl)
{
- location_t sizeof_arg_loc[3];
- tree sizeof_arg[3];
+ location_t sizeof_arg_loc[6];
+ tree sizeof_arg[6];
unsigned int i;
- for (i = 0; i < 3; i++)
+ for (i = 0; i < (alloc_size_attr ? 6 : 3); i++)
{
tree t;
@@ -2964,9 +2973,15 @@ finish_call_expr (tree fn, vec<tree, va_
sizeof_arg[i] = TREE_OPERAND (t, 0);
sizeof_arg_loc[i] = EXPR_LOCATION (t);
}
- sizeof_pointer_memaccess_warning
- (sizeof_arg_loc, fn, *args,
- sizeof_arg, same_type_ignoring_top_level_qualifiers_p);
+ if (warn_sizeof_pointer_memaccess)
+ {
+ auto same_p = same_type_ignoring_top_level_qualifiers_p;
+ sizeof_pointer_memaccess_warning (sizeof_arg_loc, fn, *args,
+ sizeof_arg, same_p);
+ }
+ if (alloc_size_attr)
+ warn_for_calloc (sizeof_arg_loc, fn, *args, sizeof_arg,
+ alloc_size_attr);
}
if ((complain & tf_warning)
--- gcc/testsuite/g++.dg/warn/Wcalloc-transposed-args-1.C.jj 2023-12-20
19:52:10.303641708 +0100
+++ gcc/testsuite/g++.dg/warn/Wcalloc-transposed-args-1.C 2023-12-20
20:16:09.239611657 +0100
@@ -0,0 +1,54 @@
+// { dg-do compile }
+// { dg-options "-Wcalloc-transposed-args" }
+
+typedef __SIZE_TYPE__ size_t;
+extern "C" void free (void *);
+extern "C" void *calloc (size_t, size_t);
+void *myfree (void *, int, int);
+void *mycalloc (int, int, size_t, size_t) __attribute__((malloc, malloc
(myfree), alloc_size (3, 4)));
+
+void
+foo (int n)
+{
+ void *p;
+ p = __builtin_calloc (1, sizeof (int));
+ __builtin_free (p);
+ p = __builtin_calloc (n, sizeof (int));
+ __builtin_free (p);
+ p = __builtin_calloc (sizeof (int), 1); // { dg-warning
"'\[^']*__builtin_calloc\[^']*' sizes specified with 'sizeof' in the earlier
argument and not in the later argument" }
+ __builtin_free (p); // { dg-message
"earlier argument should specify number of elements, later size of each
element" "" { target *-*-* } .-1 }
+ p = __builtin_calloc (sizeof (int), n); // { dg-warning
"'\[^']*__builtin_calloc\[^']*' sizes specified with 'sizeof' in the earlier
argument and not in the later argument" }
+ __builtin_free (p); // { dg-message
"earlier argument should specify number of elements, later size of each
element" "" { target *-*-* } .-1 }
+ p = __builtin_calloc ((sizeof (int)), 1); // { dg-warning
"'\[^']*__builtin_calloc\[^']*' sizes specified with 'sizeof' in the earlier
argument and not in the later argument" }
+ __builtin_free (p); // { dg-message
"earlier argument should specify number of elements, later size of each
element" "" { target *-*-* } .-1 }
+ p = __builtin_calloc (sizeof (int) + 0, 1);
+ __builtin_free (p);
+ p = __builtin_calloc (sizeof (int), sizeof (char));
+ __builtin_free (p);
+ p = __builtin_calloc (1 * sizeof (int), 1);
+ __builtin_free (p);
+ p = calloc (1, sizeof (int));
+ free (p);
+ p = calloc (n, sizeof (int));
+ free (p);
+ p = calloc (sizeof (int), 1); // { dg-warning
"'\[^']*calloc\[^']*' sizes specified with 'sizeof' in the earlier argument and
not in the later argument" }
+ free (p); // { dg-message
"earlier argument should specify number of elements, later size of each
element" "" { target *-*-* } .-1 }
+ p = calloc (sizeof (int), n); // { dg-warning
"'\[^']*calloc\[^']*' sizes specified with 'sizeof' in the earlier argument and
not in the later argument" }
+ free (p); // { dg-message
"earlier argument should specify number of elements, later size of each
element" "" { target *-*-* } .-1 }
+ p = calloc (sizeof (int), sizeof (char));
+ free (p);
+ p = calloc (1 * sizeof (int), 1);
+ free (p);
+ p = mycalloc (42, 42, 1, sizeof (int));
+ myfree (p, 42, 42);
+ p = mycalloc (42, 42, n, sizeof (int));
+ myfree (p, 42, 42);
+ p = mycalloc (42, 42, sizeof (int), 1); // { dg-warning
"'\[^']*mycalloc\[^']*' sizes specified with 'sizeof' in the earlier argument
and not in the later argument" }
+ myfree (p, 42, 42); // { dg-message
"earlier argument should specify number of elements, later size of each
element" "" { target *-*-* } .-1 }
+ p = mycalloc (42, 42, sizeof (int), n); // { dg-warning
"'\[^']*mycalloc\[^']*' sizes specified with 'sizeof' in the earlier argument
and not in the later argument" }
+ myfree (p, 42, 42); // { dg-message
"earlier argument should specify number of elements, later size of each
element" "" { target *-*-* } .-1 }
+ p = mycalloc (42, 42, sizeof (int), sizeof (char));
+ myfree (p, 42, 42);
+ p = mycalloc (42, 42, 1 * sizeof (int), 1);
+ myfree (p, 42, 42);
+}
--- gcc/testsuite/g++.dg/warn/Walloc-size-1.C.jj 2023-12-20
19:51:45.828982748 +0100
+++ gcc/testsuite/g++.dg/warn/Walloc-size-1.C 2023-12-20 20:01:40.385697949
+0100
@@ -0,0 +1,52 @@
+// Tests the warnings for insufficient allocation size.
+// { dg-do compile }
+// { dg-options "-Walloc-size -Wno-calloc-transposed-args" }
+
+struct S { int x[10]; };
+void bar (S *);
+typedef __SIZE_TYPE__ size_t;
+void *myfree (void *, int, int);
+void *mymalloc (int, int, size_t) __attribute__((malloc, malloc (myfree),
alloc_size (3)));
+void *mycalloc (int, int, size_t, size_t) __attribute__((malloc, malloc
(myfree), alloc_size (3, 4)));
+
+void
+foo (void)
+{
+ S *p = (S *) __builtin_malloc (sizeof *p);
+ __builtin_free (p);
+ p = (S *) __builtin_malloc (sizeof p); // { dg-warning "allocation of
insufficient size" }
+ __builtin_free (p);
+ p = (S *) __builtin_alloca (sizeof p); // { dg-warning "allocation of
insufficient size" }
+ bar (p);
+ p = (S *) __builtin_calloc (1, sizeof p); // { dg-warning "allocation of
insufficient size" }
+ __builtin_free (p);
+ bar ((S *) __builtin_malloc (4)); // { dg-warning "allocation of
insufficient size" }
+ __builtin_free (p);
+ p = (S *) __builtin_calloc (sizeof *p, 1);
+ __builtin_free (p);
+}
+
+void
+baz (void)
+{
+ S *p = (S *) mymalloc (42, 42, sizeof *p);
+ myfree (p, 42, 42);
+ p = (S *) mymalloc (42, 42, sizeof p); // { dg-warning "allocation of
insufficient size" }
+ myfree (p, 42, 42);
+ p = (S *) mycalloc (42, 42, 1, sizeof p); // { dg-warning "allocation of
insufficient size" }
+ myfree (p, 42, 42);
+ bar ((S *) mymalloc (42, 42, 4)); // { dg-warning "allocation of
insufficient size" }
+ myfree (p, 42, 42);
+ p = (S *) mycalloc (42, 42, sizeof *p, 1);
+ myfree (p, 42, 42);
+ p = static_cast <S *> (mycalloc (42, 42, sizeof *p, 1));
+ myfree (p, 42, 42);
+ p = static_cast <S *> (mymalloc (42, 42, sizeof *p));
+ myfree (p, 42, 42);
+ p = static_cast <S *> (mymalloc (42, 42, sizeof p)); // { dg-warning
"allocation of insufficient size" }
+ myfree (p, 42, 42);
+ p = static_cast <S *> (mycalloc (42, 42, 1, sizeof p)); // { dg-warning
"allocation of insufficient size" }
+ myfree (p, 42, 42);
+ bar (static_cast <S *> (mymalloc (42, 42, 4))); // { dg-warning
"allocation of insufficient size" }
+ myfree (p, 42, 42);
+}
Jakub
