libstdc++
macros.h
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1 // Debugging support implementation -*- C++ -*-
2 
3 // Copyright (C) 2003-2020 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file debug/macros.h
26  * This file is a GNU debug extension to the Standard C++ Library.
27  */
28 
29 #ifndef _GLIBCXX_DEBUG_MACROS_H
30 #define _GLIBCXX_DEBUG_MACROS_H 1
31 
32 /**
33  * Macros used by the implementation to verify certain
34  * properties. These macros may only be used directly by the debug
35  * wrappers. Note that these are macros (instead of the more obviously
36  * @a correct choice of making them functions) because we need line and
37  * file information at the call site, to minimize the distance between
38  * the user error and where the error is reported.
39  *
40  */
41 #define _GLIBCXX_DEBUG_VERIFY_COND_AT(_Cond,_ErrMsg,_File,_Line,_Func) \
42  if (__builtin_expect(!bool(_Cond), false)) \
43  __gnu_debug::_Error_formatter::_S_at(_File, _Line, _Func) \
44  ._ErrMsg._M_error()
45 
46 #define _GLIBCXX_DEBUG_VERIFY_AT_F(_Cond,_ErrMsg,_File,_Line,_Func) \
47  do { \
48  __glibcxx_assert_1(_Cond) \
49  { _GLIBCXX_DEBUG_VERIFY_COND_AT(_Cond,_ErrMsg,_File,_Line,_Func); } \
50  } while (false)
51 
52 #define _GLIBCXX_DEBUG_VERIFY_AT(_Cond,_ErrMsg,_File,_Line) \
53  _GLIBCXX_DEBUG_VERIFY_AT_F(_Cond,_ErrMsg,_File,_Line,__PRETTY_FUNCTION__)
54 
55 #define _GLIBCXX_DEBUG_VERIFY(_Cond,_ErrMsg) \
56  _GLIBCXX_DEBUG_VERIFY_AT_F(_Cond, _ErrMsg, __FILE__, __LINE__, \
57  __PRETTY_FUNCTION__)
58 
59 // Verify that [_First, _Last) forms a valid iterator range.
60 #define __glibcxx_check_valid_range(_First,_Last) \
61 _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__valid_range(_First, _Last), \
62  _M_message(__gnu_debug::__msg_valid_range) \
63  ._M_iterator(_First, #_First) \
64  ._M_iterator(_Last, #_Last))
65 
66 #define __glibcxx_check_valid_range_at(_First,_Last,_File,_Line,_Func) \
67 _GLIBCXX_DEBUG_VERIFY_AT_F(__gnu_debug::__valid_range(_First, _Last), \
68  _M_message(__gnu_debug::__msg_valid_range) \
69  ._M_iterator(_First, #_First) \
70  ._M_iterator(_Last, #_Last), \
71  _File,_Line,_Func)
72 
73 #define __glibcxx_check_valid_range2(_First,_Last,_Dist) \
74 _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__valid_range(_First, _Last, _Dist), \
75  _M_message(__gnu_debug::__msg_valid_range) \
76  ._M_iterator(_First, #_First) \
77  ._M_iterator(_Last, #_Last))
78 
79 #define __glibcxx_check_valid_constructor_range(_First,_Last) \
80  __gnu_debug::__check_valid_range(_First, _Last, \
81  __FILE__, __LINE__, __PRETTY_FUNCTION__)
82 
83 // Verify that [_First, _Last) forms a non-empty iterator range.
84 #define __glibcxx_check_non_empty_range(_First,_Last) \
85 _GLIBCXX_DEBUG_VERIFY(_First != _Last, \
86  _M_message(__gnu_debug::__msg_non_empty_range) \
87  ._M_iterator(_First, #_First) \
88  ._M_iterator(_Last, #_Last))
89 
90 // Verify that [_First, _First + _Size) forms a valid range.
91 #define __glibcxx_check_can_increment(_First,_Size) \
92 _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__can_advance(_First, _Size), \
93  _M_message(__gnu_debug::__msg_iter_subscript_oob) \
94  ._M_iterator(_First, #_First) \
95  ._M_integer(_Size, #_Size))
96 
97 #define __glibcxx_check_can_increment_range(_First1,_Last1,_First2) \
98  do \
99  { \
100  typename __gnu_debug::_Distance_traits<__decltype(_First1)>::__type __dist;\
101  _GLIBCXX_DEBUG_VERIFY_COND_AT( \
102  __gnu_debug::__valid_range(_First1, _Last1, __dist),\
103  _M_message(__gnu_debug::__msg_valid_range) \
104  ._M_iterator(_First1, #_First1) \
105  ._M_iterator(_Last1, #_Last1), \
106  __FILE__,__LINE__,__PRETTY_FUNCTION__); \
107  _GLIBCXX_DEBUG_VERIFY_COND_AT( \
108  __gnu_debug::__can_advance(_First2, __dist.first),\
109  _M_message(__gnu_debug::__msg_iter_subscript_oob)\
110  ._M_iterator(_First2, #_First2) \
111  ._M_integer(__dist.first), \
112  __FILE__,__LINE__,__PRETTY_FUNCTION__); \
113  } while(false)
114 
115 #define __glibcxx_check_can_decrement_range(_First1,_Last1,_First2) \
116  do \
117  { \
118  typename __gnu_debug::_Distance_traits<__decltype(_First1)>::__type __dist;\
119  _GLIBCXX_DEBUG_VERIFY_COND_AT( \
120  __gnu_debug::__valid_range(_First1, _Last1, __dist),\
121  _M_message(__gnu_debug::__msg_valid_range) \
122  ._M_iterator(_First1, #_First1) \
123  ._M_iterator(_Last1, #_Last1), \
124  __FILE__,__LINE__,__PRETTY_FUNCTION__); \
125  _GLIBCXX_DEBUG_VERIFY_COND_AT( \
126  __gnu_debug::__can_advance(_First2, -__dist.first),\
127  _M_message(__gnu_debug::__msg_iter_subscript_oob)\
128  ._M_iterator(_First2, #_First2) \
129  ._M_integer(-__dist.first), \
130  __FILE__,__LINE__,__PRETTY_FUNCTION__); \
131  } while(false)
132 
133 /** Verify that we can insert into *this with the iterator _Position.
134  * Insertion into a container at a specific position requires that
135  * the iterator be nonsingular, either dereferenceable or past-the-end,
136  * and that it reference the sequence we are inserting into. Note that
137  * this macro is only valid when the container is a_Safe_sequence and
138  * the iterator is a _Safe_iterator.
139 */
140 #define __glibcxx_check_insert(_Position) \
141 _GLIBCXX_DEBUG_VERIFY(!_Position._M_singular(), \
142  _M_message(__gnu_debug::__msg_insert_singular) \
143  ._M_sequence(*this, "this") \
144  ._M_iterator(_Position, #_Position)); \
145 _GLIBCXX_DEBUG_VERIFY(_Position._M_attached_to(this), \
146  _M_message(__gnu_debug::__msg_insert_different) \
147  ._M_sequence(*this, "this") \
148  ._M_iterator(_Position, #_Position))
149 
150 /** Verify that we can insert into *this after the iterator _Position.
151  * Insertion into a container after a specific position requires that
152  * the iterator be nonsingular, either dereferenceable or before-begin,
153  * and that it reference the sequence we are inserting into. Note that
154  * this macro is only valid when the container is a_Safe_sequence and
155  * the iterator is a _Safe_iterator.
156 */
157 #define __glibcxx_check_insert_after(_Position) \
158 __glibcxx_check_insert(_Position); \
159 _GLIBCXX_DEBUG_VERIFY(!_Position._M_is_end(), \
160  _M_message(__gnu_debug::__msg_insert_after_end) \
161  ._M_sequence(*this, "this") \
162  ._M_iterator(_Position, #_Position))
163 
164 /** Verify that we can insert the values in the iterator range
165  * [_First, _Last) into *this with the iterator _Position. Insertion
166  * into a container at a specific position requires that the iterator
167  * be nonsingular (i.e., either dereferenceable or past-the-end),
168  * that it reference the sequence we are inserting into, and that the
169  * iterator range [_First, _Last) is a valid (possibly empty)
170  * range which does not reference the sequence we are inserting into.
171  * Note that this macro is only valid when the container is a
172  * _Safe_sequence and the _Position iterator is a _Safe_iterator.
173 */
174 #define __glibcxx_check_insert_range(_Position,_First,_Last,_Dist) \
175 __glibcxx_check_valid_range2(_First,_Last,_Dist); \
176 __glibcxx_check_insert(_Position); \
177 _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__foreign_iterator(_Position,_First,_Last),\
178  _M_message(__gnu_debug::__msg_insert_range_from_self)\
179  ._M_iterator(_First, #_First) \
180  ._M_iterator(_Last, #_Last) \
181  ._M_sequence(*this, "this"))
182 
183 /** Verify that we can insert the values in the iterator range
184  * [_First, _Last) into *this after the iterator _Position. Insertion
185  * into a container after a specific position requires that the iterator
186  * be nonsingular (i.e., either dereferenceable or past-the-end),
187  * that it reference the sequence we are inserting into, and that the
188  * iterator range [_First, _Last) is a valid (possibly empty)
189  * range which does not reference the sequence we are inserting into.
190  * Note that this macro is only valid when the container is a
191  * _Safe_sequence and the _Position iterator is a _Safe_iterator.
192 */
193 #define __glibcxx_check_insert_range_after(_Position,_First,_Last,_Dist)\
194 __glibcxx_check_valid_range2(_First,_Last,_Dist); \
195 __glibcxx_check_insert_after(_Position); \
196 _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__foreign_iterator(_Position,_First,_Last),\
197  _M_message(__gnu_debug::__msg_insert_range_from_self)\
198  ._M_iterator(_First, #_First) \
199  ._M_iterator(_Last, #_Last) \
200  ._M_sequence(*this, "this"))
201 
202 /** Verify that we can erase the element referenced by the iterator
203  * _Position. We can erase the element if the _Position iterator is
204  * dereferenceable and references this sequence.
205 */
206 #define __glibcxx_check_erase(_Position) \
207 _GLIBCXX_DEBUG_VERIFY(_Position._M_dereferenceable(), \
208  _M_message(__gnu_debug::__msg_erase_bad) \
209  ._M_sequence(*this, "this") \
210  ._M_iterator(_Position, #_Position)); \
211 _GLIBCXX_DEBUG_VERIFY(_Position._M_attached_to(this), \
212  _M_message(__gnu_debug::__msg_erase_different) \
213  ._M_sequence(*this, "this") \
214  ._M_iterator(_Position, #_Position))
215 
216 /** Verify that we can erase the element after the iterator
217  * _Position. We can erase the element if the _Position iterator is
218  * before a dereferenceable one and references this sequence.
219 */
220 #define __glibcxx_check_erase_after(_Position) \
221 _GLIBCXX_DEBUG_VERIFY(_Position._M_before_dereferenceable(), \
222  _M_message(__gnu_debug::__msg_erase_after_bad) \
223  ._M_sequence(*this, "this") \
224  ._M_iterator(_Position, #_Position)); \
225 _GLIBCXX_DEBUG_VERIFY(_Position._M_attached_to(this), \
226  _M_message(__gnu_debug::__msg_erase_different) \
227  ._M_sequence(*this, "this") \
228  ._M_iterator(_Position, #_Position))
229 
230 /** Verify that we can erase the elements in the iterator range
231  * [_First, _Last). We can erase the elements if [_First, _Last) is a
232  * valid iterator range within this sequence.
233 */
234 #define __glibcxx_check_erase_range(_First,_Last) \
235 __glibcxx_check_valid_range(_First,_Last); \
236 _GLIBCXX_DEBUG_VERIFY(_First._M_attached_to(this), \
237  _M_message(__gnu_debug::__msg_erase_different) \
238  ._M_sequence(*this, "this") \
239  ._M_iterator(_First, #_First) \
240  ._M_iterator(_Last, #_Last))
241 
242 /** Verify that we can erase the elements in the iterator range
243  * (_First, _Last). We can erase the elements if (_First, _Last) is a
244  * valid iterator range within this sequence.
245 */
246 #define __glibcxx_check_erase_range_after(_First,_Last) \
247 _GLIBCXX_DEBUG_VERIFY(_First._M_can_compare(_Last), \
248  _M_message(__gnu_debug::__msg_erase_different) \
249  ._M_sequence(*this, "this") \
250  ._M_iterator(_First, #_First) \
251  ._M_iterator(_Last, #_Last)); \
252 _GLIBCXX_DEBUG_VERIFY(_First._M_attached_to(this), \
253  _M_message(__gnu_debug::__msg_erase_different) \
254  ._M_sequence(*this, "this") \
255  ._M_iterator(_First, #_First)); \
256 _GLIBCXX_DEBUG_VERIFY(_First != _Last, \
257  _M_message(__gnu_debug::__msg_valid_range2) \
258  ._M_sequence(*this, "this") \
259  ._M_iterator(_First, #_First) \
260  ._M_iterator(_Last, #_Last)); \
261 _GLIBCXX_DEBUG_VERIFY(_First._M_incrementable(), \
262  _M_message(__gnu_debug::__msg_valid_range2) \
263  ._M_sequence(*this, "this") \
264  ._M_iterator(_First, #_First) \
265  ._M_iterator(_Last, #_Last)); \
266 _GLIBCXX_DEBUG_VERIFY(!_Last._M_is_before_begin(), \
267  _M_message(__gnu_debug::__msg_valid_range2) \
268  ._M_sequence(*this, "this") \
269  ._M_iterator(_First, #_First) \
270  ._M_iterator(_Last, #_Last)) \
271 
272 // Verify that the subscript _N is less than the container's size.
273 #define __glibcxx_check_subscript(_N) \
274 _GLIBCXX_DEBUG_VERIFY(_N < this->size(), \
275  _M_message(__gnu_debug::__msg_subscript_oob) \
276  ._M_sequence(*this, "this") \
277  ._M_integer(_N, #_N) \
278  ._M_integer(this->size(), "size"))
279 
280 // Verify that the bucket _N is less than the container's buckets count.
281 #define __glibcxx_check_bucket_index(_N) \
282 _GLIBCXX_DEBUG_VERIFY(_N < this->bucket_count(), \
283  _M_message(__gnu_debug::__msg_bucket_index_oob) \
284  ._M_sequence(*this, "this") \
285  ._M_integer(_N, #_N) \
286  ._M_integer(this->bucket_count(), "size"))
287 
288 // Verify that the container is nonempty
289 #define __glibcxx_check_nonempty() \
290 _GLIBCXX_DEBUG_VERIFY(! this->empty(), \
291  _M_message(__gnu_debug::__msg_empty) \
292  ._M_sequence(*this, "this"))
293 
294 // Verify that a predicate is irreflexive
295 #define __glibcxx_check_irreflexive(_First,_Last) \
296  _GLIBCXX_DEBUG_VERIFY(_First == _Last || !(*_First < *_First), \
297  _M_message(__gnu_debug::__msg_irreflexive_ordering) \
298  ._M_iterator_value_type(_First, "< operator type"))
299 
300 #if __cplusplus >= 201103L
301 # define __glibcxx_check_irreflexive2(_First,_Last) \
302  _GLIBCXX_DEBUG_VERIFY(_First == _Last \
303  || __gnu_debug::__is_irreflexive(_First), \
304  _M_message(__gnu_debug::__msg_irreflexive_ordering) \
305  ._M_iterator_value_type(_First, "< operator type"))
306 #else
307 # define __glibcxx_check_irreflexive2(_First,_Last)
308 #endif
309 
310 #define __glibcxx_check_irreflexive_pred(_First,_Last,_Pred) \
311  _GLIBCXX_DEBUG_VERIFY(_First == _Last || !_Pred(*_First, *_First), \
312  _M_message(__gnu_debug::__msg_irreflexive_ordering) \
313  ._M_instance(_Pred, "functor") \
314  ._M_iterator_value_type(_First, "ordered type"))
315 
316 #if __cplusplus >= 201103L
317 # define __glibcxx_check_irreflexive_pred2(_First,_Last,_Pred) \
318  _GLIBCXX_DEBUG_VERIFY(_First == _Last \
319  ||__gnu_debug::__is_irreflexive_pred(_First, _Pred), \
320  _M_message(__gnu_debug::__msg_irreflexive_ordering) \
321  ._M_instance(_Pred, "functor") \
322  ._M_iterator_value_type(_First, "ordered type"))
323 #else
324 # define __glibcxx_check_irreflexive_pred2(_First,_Last,_Pred)
325 #endif
326 
327 // Verify that the iterator range [_First, _Last) is sorted
328 #define __glibcxx_check_sorted(_First,_Last) \
329 __glibcxx_check_valid_range(_First,_Last); \
330 __glibcxx_check_irreflexive(_First,_Last); \
331  _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__check_sorted( \
332  __gnu_debug::__base(_First), \
333  __gnu_debug::__base(_Last)), \
334  _M_message(__gnu_debug::__msg_unsorted) \
335  ._M_iterator(_First, #_First) \
336  ._M_iterator(_Last, #_Last))
337 
338 /** Verify that the iterator range [_First, _Last) is sorted by the
339  predicate _Pred. */
340 #define __glibcxx_check_sorted_pred(_First,_Last,_Pred) \
341 __glibcxx_check_valid_range(_First,_Last); \
342 __glibcxx_check_irreflexive_pred(_First,_Last,_Pred); \
343 _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__check_sorted( \
344  __gnu_debug::__base(_First), \
345  __gnu_debug::__base(_Last), _Pred), \
346  _M_message(__gnu_debug::__msg_unsorted_pred) \
347  ._M_iterator(_First, #_First) \
348  ._M_iterator(_Last, #_Last) \
349  ._M_string(#_Pred))
350 
351 // Special variant for std::merge, std::includes, std::set_*
352 #define __glibcxx_check_sorted_set(_First1,_Last1,_First2) \
353 __glibcxx_check_valid_range(_First1,_Last1); \
354 _GLIBCXX_DEBUG_VERIFY( \
355  __gnu_debug::__check_sorted_set(__gnu_debug::__base(_First1), \
356  __gnu_debug::__base(_Last1), _First2),\
357  _M_message(__gnu_debug::__msg_unsorted) \
358  ._M_iterator(_First1, #_First1) \
359  ._M_iterator(_Last1, #_Last1))
360 
361 // Likewise with a _Pred.
362 #define __glibcxx_check_sorted_set_pred(_First1,_Last1,_First2,_Pred) \
363 __glibcxx_check_valid_range(_First1,_Last1); \
364 _GLIBCXX_DEBUG_VERIFY( \
365  __gnu_debug::__check_sorted_set(__gnu_debug::__base(_First1), \
366  __gnu_debug::__base(_Last1), \
367  _First2, _Pred), \
368  _M_message(__gnu_debug::__msg_unsorted_pred) \
369  ._M_iterator(_First1, #_First1) \
370  ._M_iterator(_Last1, #_Last1) \
371  ._M_string(#_Pred))
372 
373 /** Verify that the iterator range [_First, _Last) is partitioned
374  w.r.t. the value _Value. */
375 #define __glibcxx_check_partitioned_lower(_First,_Last,_Value) \
376 __glibcxx_check_valid_range(_First,_Last); \
377 _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__check_partitioned_lower( \
378  __gnu_debug::__base(_First), \
379  __gnu_debug::__base(_Last), _Value), \
380  _M_message(__gnu_debug::__msg_unpartitioned) \
381  ._M_iterator(_First, #_First) \
382  ._M_iterator(_Last, #_Last) \
383  ._M_string(#_Value))
384 
385 #define __glibcxx_check_partitioned_upper(_First,_Last,_Value) \
386 __glibcxx_check_valid_range(_First,_Last); \
387 _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__check_partitioned_upper( \
388  __gnu_debug::__base(_First), \
389  __gnu_debug::__base(_Last), _Value), \
390  _M_message(__gnu_debug::__msg_unpartitioned) \
391  ._M_iterator(_First, #_First) \
392  ._M_iterator(_Last, #_Last) \
393  ._M_string(#_Value))
394 
395 /** Verify that the iterator range [_First, _Last) is partitioned
396  w.r.t. the value _Value and predicate _Pred. */
397 #define __glibcxx_check_partitioned_lower_pred(_First,_Last,_Value,_Pred) \
398 __glibcxx_check_valid_range(_First,_Last); \
399 _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__check_partitioned_lower( \
400  __gnu_debug::__base(_First), \
401  __gnu_debug::__base(_Last), _Value, _Pred), \
402  _M_message(__gnu_debug::__msg_unpartitioned_pred) \
403  ._M_iterator(_First, #_First) \
404  ._M_iterator(_Last, #_Last) \
405  ._M_string(#_Pred) \
406  ._M_string(#_Value))
407 
408 /** Verify that the iterator range [_First, _Last) is partitioned
409  w.r.t. the value _Value and predicate _Pred. */
410 #define __glibcxx_check_partitioned_upper_pred(_First,_Last,_Value,_Pred) \
411 __glibcxx_check_valid_range(_First,_Last); \
412 _GLIBCXX_DEBUG_VERIFY(__gnu_debug::__check_partitioned_upper( \
413  __gnu_debug::__base(_First), \
414  __gnu_debug::__base(_Last), _Value, _Pred), \
415  _M_message(__gnu_debug::__msg_unpartitioned_pred) \
416  ._M_iterator(_First, #_First) \
417  ._M_iterator(_Last, #_Last) \
418  ._M_string(#_Pred) \
419  ._M_string(#_Value))
420 
421 // Verify that the iterator range [_First, _Last) is a heap
422 #define __glibcxx_check_heap(_First,_Last) \
423  _GLIBCXX_DEBUG_VERIFY(std::__is_heap(__gnu_debug::__base(_First), \
424  __gnu_debug::__base(_Last)), \
425  _M_message(__gnu_debug::__msg_not_heap) \
426  ._M_iterator(_First, #_First) \
427  ._M_iterator(_Last, #_Last))
428 
429 /** Verify that the iterator range [_First, _Last) is a heap
430  w.r.t. the predicate _Pred. */
431 #define __glibcxx_check_heap_pred(_First,_Last,_Pred) \
432  _GLIBCXX_DEBUG_VERIFY(std::__is_heap(__gnu_debug::__base(_First), \
433  __gnu_debug::__base(_Last), \
434  _Pred), \
435  _M_message(__gnu_debug::__msg_not_heap_pred) \
436  ._M_iterator(_First, #_First) \
437  ._M_iterator(_Last, #_Last) \
438  ._M_string(#_Pred))
439 
440 // Verify that load factor is positive
441 #define __glibcxx_check_max_load_factor(_F) \
442 _GLIBCXX_DEBUG_VERIFY(_F > 0.0f, \
443  _M_message(__gnu_debug::__msg_valid_load_factor) \
444  ._M_sequence(*this, "this"))
445 
446 #define __glibcxx_check_equal_allocs(_This, _Other) \
447 _GLIBCXX_DEBUG_VERIFY(_This.get_allocator() == _Other.get_allocator(), \
448  _M_message(__gnu_debug::__msg_equal_allocs) \
449  ._M_sequence(_This, "this"))
450 
451 #define __glibcxx_check_string(_String) _GLIBCXX_DEBUG_PEDASSERT(_String != 0)
452 #define __glibcxx_check_string_len(_String,_Len) \
453  _GLIBCXX_DEBUG_PEDASSERT(_String != 0 || _Len == 0)
454 
455 #endif