2007-09-23 Jakub Jelinek <jakub@redhat.com>
+ * expr.c (expand_expr_real_1) <case CALL_EXPR>: Use get_callee_fndecl
+ instead of checking CALL_EXPR_FN directly to test for builtins.
+ If error or warning attributes are present, print
+ error resp. warning.
+ * c-common.c (handle_error_attribute): New function.
+ (c_common_attribute_table): Add error and warning
+ attributes.
+ * doc/extend.texi: Document error and warning attributes.
+
* tree.h (block_nonartificial_location): New prototype.
* tree.c (block_nonartificial_location): New function.
* dwarf2out.c (gen_subprogram_die): Add DW_AT_artificial
static tree handle_gnu_inline_attribute (tree *, tree, tree, int, bool *);
static tree handle_artificial_attribute (tree *, tree, tree, int, bool *);
static tree handle_flatten_attribute (tree *, tree, tree, int, bool *);
+static tree handle_error_attribute (tree *, tree, tree, int, bool *);
static tree handle_used_attribute (tree *, tree, tree, int, bool *);
static tree handle_unused_attribute (tree *, tree, tree, int, bool *);
static tree handle_externally_visible_attribute (tree *, tree, tree, int,
handle_cold_attribute },
{ "hot", 0, 0, true, false, false,
handle_hot_attribute },
+ { "warning", 1, 1, true, false, false,
+ handle_error_attribute },
+ { "error", 1, 1, true, false, false,
+ handle_error_attribute },
{ NULL, 0, 0, false, false, false, NULL }
};
return NULL_TREE;
}
+/* Handle a "warning" or "error" attribute; arguments as in
+ struct attribute_spec.handler. */
+
+static tree
+handle_error_attribute (tree *node, tree name, tree args,
+ int ARG_UNUSED (flags), bool *no_add_attrs)
+{
+ if (TREE_CODE (*node) == FUNCTION_DECL
+ || TREE_CODE (TREE_VALUE (args)) == STRING_CST)
+ /* Do nothing else, just set the attribute. We'll get at
+ it later with lookup_attribute. */
+ ;
+ else
+ {
+ warning (OPT_Wattributes, "%qE attribute ignored", name);
+ *no_add_attrs = true;
+ }
+
+ return NULL_TREE;
+}
/* Handle a "used" attribute; arguments as in
struct attribute_spec.handler. */
@code{destructor}, @code{used}, @code{unused}, @code{deprecated},
@code{weak}, @code{malloc}, @code{alias}, @code{warn_unused_result},
@code{nonnull}, @code{gnu_inline}, @code{externally_visible},
-@code{hot}, @code{cold} and @code{artificial}.
+@code{hot}, @code{cold}, @code{artificial}, @code{error}
+and @code{warning}.
Several other attributes are defined for functions on particular
target systems. Other attributes, including @code{section} are
supported for variables declarations (@pxref{Variable Attributes}) and
the current inlining parameters. The @code{flatten} attribute only works
reliably in unit-at-a-time mode.
+@item error ("@var{message}")
+@cindex @code{error} function attribute
+If this attribute is used on a function declaration and a call to such a function
+is not eliminated through dead code elimination or other optimizations, an error
+which will include @var{message} will be diagnosed. This is useful
+for compile time checking, especially together with @code{__builtin_constant_p}
+and inline functions where checking the inline function arguments is not
+possible through @code{extern char [(condition) ? 1 : -1];} tricks.
+While it is possible to leave the function undefined and thus invoke
+a link failure, when using this attribute the problem will be diagnosed
+earlier and with exact location of the call even in presence of inline
+functions or when not emitting debugging information.
+
+@item warning ("@var{message}")
+@cindex @code{warning} function attribute
+If this attribute is used on a function declaration and a call to such a function
+is not eliminated through dead code elimination or other optimizations, a warning
+which will include @var{message} will be diagnosed. This is useful
+for compile time checking, especially together with @code{__builtin_constant_p}
+and inline functions. While it is possible to define the function with
+a message in @code{.gnu.warning*} section, when using this attribute the problem
+will be diagnosed earlier and with exact location of the call even in presence
+of inline functions or when not emitting debugging information.
+
@item cdecl
@cindex functions that do pop the argument stack on the 386
@opindex mrtd
inlining. */
if (CALL_EXPR_VA_ARG_PACK (exp))
error ("invalid use of %<__builtin_va_arg_pack ()%>");
- /* Check for a built-in function. */
- if (TREE_CODE (CALL_EXPR_FN (exp)) == ADDR_EXPR
- && (TREE_CODE (TREE_OPERAND (CALL_EXPR_FN (exp), 0))
- == FUNCTION_DECL)
- && DECL_BUILT_IN (TREE_OPERAND (CALL_EXPR_FN (exp), 0)))
- {
- if (DECL_BUILT_IN_CLASS (TREE_OPERAND (CALL_EXPR_FN (exp), 0))
- == BUILT_IN_FRONTEND)
- return lang_hooks.expand_expr (exp, original_target,
- tmode, modifier,
- alt_rtl);
- else
- return expand_builtin (exp, target, subtarget, tmode, ignore);
- }
-
+ {
+ tree fndecl = get_callee_fndecl (exp), attr;
+
+ if (fndecl
+ && (attr = lookup_attribute ("error",
+ DECL_ATTRIBUTES (fndecl))) != NULL)
+ error ("call to %qs declared with attribute error: %s",
+ lang_hooks.decl_printable_name (fndecl, 1),
+ TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr))));
+ if (fndecl
+ && (attr = lookup_attribute ("warning",
+ DECL_ATTRIBUTES (fndecl))) != NULL)
+ warning (0, "call to %qs declared with attribute warning: %s",
+ lang_hooks.decl_printable_name (fndecl, 1),
+ TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr))));
+
+ /* Check for a built-in function. */
+ if (fndecl && DECL_BUILT_IN (fndecl))
+ {
+ if (DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_FRONTEND)
+ return lang_hooks.expand_expr (exp, original_target,
+ tmode, modifier, alt_rtl);
+ else
+ return expand_builtin (exp, target, subtarget, tmode, ignore);
+ }
+ }
return expand_call (exp, target, ignore);
case NON_LVALUE_EXPR:
2007-09-23 Jakub Jelinek <jakub@redhat.com>
+ * gcc.dg/va-arg-pack-len-1.c: Use error and warning
+ attributes.
+ * gcc.dg/va-arg-pack-len-2.c: New test.
+ * g++.dg/ext/va-arg-pack-len-1.C: Use error and warning
+ attributes.
+ * g++.dg/ext/va-arg-pack-len-2.C: New test.
+
PR middle-end/28755
* gcc.dg/pr28755.c: New test.
#include <stdarg.h>
-extern "C" int warn_open_missing_mode (void);
-extern "C" int warn_open_too_many_arguments (void);
+extern "C" int error_open_missing_mode (void)
+ __attribute__((__error__ ("open with O_CREAT needs 3 arguments, only 2 were given")));
+extern "C" int warn_open_too_many_arguments (void)
+ __attribute__((__warning__ ("open called with more than 3 arguments")));
extern "C" void abort (void);
char expected_char;
{
if ((oflag & 0x40) != 0 && __builtin_va_arg_pack_len () < 1)
{
- warn_open_missing_mode ();
+ error_open_missing_mode ();
return myopen2 (path, oflag);
}
return myopenva (path, oflag, __builtin_va_arg_pack ());
--- /dev/null
+// { dg-do compile }
+// { dg-options "-O2" }
+
+#include <stdarg.h>
+
+extern int error_open_missing_mode (void)
+ __attribute__((__error__ ("open with O_CREAT needs 3 arguments, only 2 were given")));
+extern int warn_open_too_many_arguments (void)
+ __attribute__((__warning__ ("open called with more than 3 arguments")));
+
+extern int myopen2 (const char *path, int oflag);
+extern int myopenva (const char *path, int oflag, ...);
+
+extern inline __attribute__((always_inline, gnu_inline)) int
+myopen (const char *path, int oflag, ...)
+{
+ if (__builtin_va_arg_pack_len () > 1)
+ warn_open_too_many_arguments (); // { dg-warning "called with more than 3" }
+
+ if (__builtin_constant_p (oflag))
+ {
+ if ((oflag & 0x40) != 0 && __builtin_va_arg_pack_len () < 1)
+ {
+ error_open_missing_mode (); // { dg-error "needs 3 arguments, only 2 were given" }
+ return myopen2 (path, oflag);
+ }
+ return myopenva (path, oflag, __builtin_va_arg_pack ());
+ }
+
+ if (__builtin_va_arg_pack_len () < 1)
+ return myopen2 (path, oflag);
+
+ return myopenva (path, oflag, __builtin_va_arg_pack ());
+}
+
+int
+main (void)
+{
+ myopen ("h", 0x43);
+ myopen ("i", 0x43, 0644, 0655);
+ return 0;
+}
#include <stdarg.h>
-extern int warn_open_missing_mode (void);
-extern int warn_open_too_many_arguments (void);
+extern int error_open_missing_mode (void)
+ __attribute__((__error__ ("open with O_CREAT needs 3 arguments, only 2 were given")));
+extern int warn_open_too_many_arguments (void)
+ __attribute__((__warning__ ("open called with more than 3 arguments")));
extern void abort (void);
char expected_char;
{
if ((oflag & 0x40) != 0 && __builtin_va_arg_pack_len () < 1)
{
- warn_open_missing_mode ();
+ error_open_missing_mode ();
return myopen2 (path, oflag);
}
return myopenva (path, oflag, __builtin_va_arg_pack ());
--- /dev/null
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+#include <stdarg.h>
+
+extern int error_open_missing_mode (void)
+ __attribute__((__error__ ("open with O_CREAT needs 3 arguments, only 2 were given")));
+extern int warn_open_too_many_arguments (void)
+ __attribute__((__warning__ ("open called with more than 3 arguments")));
+
+extern int myopen2 (const char *path, int oflag);
+extern int myopenva (const char *path, int oflag, ...);
+
+extern inline __attribute__((always_inline, gnu_inline)) int
+myopen (const char *path, int oflag, ...)
+{
+ if (__builtin_va_arg_pack_len () > 1)
+ warn_open_too_many_arguments (); /* { dg-warning "called with more than 3" } */
+
+ if (__builtin_constant_p (oflag))
+ {
+ if ((oflag & 0x40) != 0 && __builtin_va_arg_pack_len () < 1)
+ {
+ error_open_missing_mode (); /* { dg-error "needs 3 arguments, only 2 were given" } */
+ return myopen2 (path, oflag);
+ }
+ return myopenva (path, oflag, __builtin_va_arg_pack ());
+ }
+
+ if (__builtin_va_arg_pack_len () < 1)
+ return myopen2 (path, oflag);
+
+ return myopenva (path, oflag, __builtin_va_arg_pack ());
+}
+
+int
+main (void)
+{
+ myopen ("h", 0x43);
+ myopen ("i", 0x43, 0644, 0655);
+ return 0;
+}