Clang - C Defect Report Status

# C Defect Report Support in Clang

## C defect report implementation status

This page tracks which C defect reports are implemented within Clang.

The implementation status for defect reports against the C Standard are currently under investigation. Any defect report whose status in Clang is currently unknown will be marked in purple.

The LLVM bug tracker uses the "c", "c99", "c11", "c17", and "c23" labels to track known bugs with Clang's language conformance.

Number | Status | Issue title | Available in Clang?
--- | --- | --- | ---
1 | C89 | Do functions return values by copying? | Yes
2 | NAD | Subclause 6.8.3.2: Semantics of # | Unknown
3 | NAD | Subclause 6.1.8: Preprocessing numbers | Unknown
4 | NAD | Are multiple definitions of unused identifiers with external linkage permitted? | Yes
5 | NAD | May a conforming implementation define and recognize a pragma which would change the semantics of the language? | Yes
6 | C89 | It is unclear how the strtoul function behaves when presented with a subject sequence that begins with a minus sign | N/A
7 | NAD | Are declarations of the form struct-or-union identifier ; permitted after the identifier tag has already been declared? | Yes
8 | NAD | Can a conforming C compiler to perform dead-store elimination? | Yes
9 | C89 | Use of typedef names in parameter declarations | No
10 | NAD | Is a typedef to an incomplete type legal? | Yes
11 | C89 | Merging of declarations for linked identifier | Yes
12 | NAD | Is it valid to take the address of a dereferenced void pointer? | Yes
13 | C89 | Compatible and composite function types | Yes
14 | C89 | Issues with setjmp and fscanf descriptions | N/A
15 | NAD | What is the promoted type of a plain int bit-field? | Yes
16 | C89 | What does static storage duration do when zero for the type is not all zero bits? | Unknown
17 | C89 | 39 unrelated questions about C89 | Unknown
18 | NAD | How does fscanf behave in the presence of multibyte characters? | N/A
19 | NAD | Definition of the term "printing character" and isgraph() | N/A
20 | NAD | Is a compiler which allows the Relaxed Ref/Def linkage model to be considered a conforming compiler? | Yes
21 | C89 | What is the result of: printf("%#.4o", 345);? | N/A
22 | C89 | What is the result of: strtod("100ergs", &ptr);? | N/A
23 | NAD | what is the result of strtod("0.0e99999", &ptr);? | N/A
24 | NAD | In subclause 7.10.1.4 The strtod function: What does '"C" locale' mean? | N/A
25 | NAD | What is meant by 'representable floating-point value?' | Yes
26 | NAD | Can a strictly conforming program contain a string literal with '$' or '@'? | Yes
27 | C89 | Can there be characters in the character set that are not in the required source character set? | Yes
28 | NAD | Do object access rules apply to dynamically allocated objects? | Unknown
29 | NAD | Do two types have to have the same tag to be compatible? | No
30 | NAD | Can 'sin(DBL_MAX)' result in 'errno' being set to 'EDOM'? | N/A
31 | NAD | Can constant expressions overflow? | Yes
32 | NAD | Must implementations diagnose extensions to the constant evaluation rules? | No
33 | NAD | Conformance questions around 'shall' violations outside of constraints sections | Yes
34 | C89 | External declarations in different scopes | Yes
35 | NAD | Questions about definition of functions without a prototype | Partial Tags declared directly within an identifier list are incorrectly scoped to the prototype rather than to the function body.
36 | NAD | May floating-point constants be represented with more precision than implied by its type? | Yes
37 | NAD | Questions about multibyte characters and Unicode | Yes
38 | NAD | Questions about argument substitution during macro expansion | Yes
39 | NAD | Questions about the "C" locale | Yes
40 | NAD | 9 unrelated questions about C89 | Partial Question 6 has full support, the rest of the questions are currently unknown.
41 | NAD | Do characters defined in 5.2.1 impact 7.3.1? | N/A
42 | NAD | On the behavior of library functions and overlapping objects | N/A
43 | C89 | On the definition of the NULL macro | Yes
44 | NAD | On the result of the offsetof macro | Yes
45 | NAD | Is the behavior of freopen defined when the file is invalid? | N/A
46 | NAD | Use of typedef names in parameter declarations | Yes
47 | NAD | Questions about declaration conformance | Yes
48 | NAD | Clarifications on the abort() function | N/A
49 | C89 | Can strxfrm() output more characters than were input? | N/A
50 | NAD | Do wide string literals implicitly include <stddef.h>? | Yes
51 | NAD | Question on pointer arithmetic | Yes
52 | C89 | Editorial corrections | Yes
53 | C89 | Accessing a pointer to a function with a prototype through a pointer to pointer to function without a prototype | Yes
54 | C89 | Can the string handling functions have a length of 0? | N/A
55 | C89 | Signal handler macros should have distinct values | N/A
56 | NAD | Floating-point representation precision requirements | Yes
57 | NAD | Is there an integral type for every pointer? | Yes
58 | NAD | Is there a limit on the number of digits processed by scanf and strtdo? | N/A
59 | NAD | Do types have to be completed? | Yes
60 | C89 | Array initialization from a string literal | Yes
61 | NAD | Whitespace in scanf format string | N/A
62 | NAD | Can the rename function be defined to fail? | N/A
63 | Dup | Floating-point representation precision requirements | Duplicate of 56
64 | NAD | Null pointer constants | Yes
65 | C89 | Questions on locales | N/A
66 | NAD | Another question on locales | N/A
67 | NAD | Integer and integral type confusion | Yes
68 | NAD | 'char' and signed vs unsigned integer types | Yes
69 | NAD | Questions about the representation of integer types | Yes
70 | NAD | Interchangeability of function arguments | Yes
71 | C89 | Enumerated types | Yes
72 | NAD | Definition of object and pointer arithmetic | Unknown
73 | NAD | Definition of object and array access | Unknown
74 | NAD | Alignment and structure padding | Unknown
75 | NAD | Alignment of allocated memory | N/A
76 | Open | Pointers to the end of arrays | Not resolved
77 | NAD | Stability of addresses | Yes
78 | NAD | Uniqueness of addresses | Unknown
79 | NAD | Constancy of system library function addresses | N/A
80 | C89 | Merging of string constants | Yes
81 | NAD | Left shift operator | Yes
82 | C89 | Multiple varargs | Unknown
83 | C89 | Use of library functions | N/A
84 | NAD | Incomplete type in function declaration | Yes
85 | C89 | Returning from main | Yes
86 | NAD | Object-like macros in system headers | Yes
87 | NAD | Order of evaluation | Unknown
88 | NAD | Compatibility of incomplete types | Yes
89 | C89 | Multiple definitions of macros | Yes
90 | NAD | Multibyte characters in formats | N/A
91 | NAD | Multibyte encodings | Yes
92 | Dup | Partial initialization of strings | Duplicate of 60
93 | C89 | Reservation of identifiers | Yes
94 | NAD | Are constraints on function return the same as assignment? | Yes
95 | NAD | Is initialization as constrained as assignment? | Yes
96 | NAD | Arrays of incomplete types | Yes
97 | Dup | Use of offsetof with an incomplete type | Duplicate of 40
98 | NAD | Pre/post increment/decrement of function or incomplete types | Yes
99 | NAD | ANSI/ISO C Defect report #rfg6 | Unknown
100 | Dup | Defect with the return statement | Duplicate of 1
101 | C89 | Type qualifiers and "as if by assignment" | Yes
102 | NAD | Tag redeclaration constraints | Yes
103 | NAD | Formal parameters of incomplete type | Yes
104 | Dup | Incomplete tag types in a parameter list | Duplicate of 84
105 | Dup | Precedence of requirements on compatible types | Duplicate of 17
106 | NAD | When can you dereference a void pointer? | Yes
107 | NAD | Type requirements of the assert macro parameter | N/A
108 | NAD | Can a macro identifier hide a keyword? | Yes
109 | NAD | Are undefined values and undefined behavior the same? | Yes
110 | Dup | Formal parameters having array-of-non-object types | Duplicate of 47
111 | NAD | Conversion of pointer-to-qualified type values to type (void*) values | Yes
112 | NAD | Null pointer constants and relational comparisons | Yes
113 | NAD | Return expressions in functions declared to return qualified void | Yes
114 | NAD | Initialization of multi-dimensional char array objects | Yes
115 | NAD | Member declarators as declarators | Yes
116 | NAD | Implicit unary & applied to register arrays | Yes
117 | NAD | Abstract semantics, sequence points, and expression evaluation | Yes
118 | C89 | Completion point for enumerated types | Yes
119 | NAD | Initialization of multi-dimensional array objects | Yes
120 | NAD | Semantics of assignment to (and initialization of) bit-fields | Yes
121 | NAD | Conversions of pointer values to integral types | Yes
122 | Dup | Conversion/widening of bit-fields | Duplicate of 15
123 | NAD | 'Type categories' and qualified types | Yes
124 | C89 | Casts to 'a void type' versus casts to 'the void type' | Yes
125 | NAD | Using things declared as 'extern (qualified) void' | Yes
126 | NAD | What does 'synonym' mean with respect to typedef names? | Yes
127 | Dup | Composite type of an enumerated type and an integral type | Duplicate of 13
128 | NAD | Editorial issue relating to tag declarations in type specifiers | Yes
129 | NAD | Tags and name spaces | Yes
130 | NAD | Guarantees when writing text to a stream | N/A
131 | C89 | const member qualification and assignment | Yes
132 | Dup | Can undefined behavior occur at translation time, or only at run time? | Duplicate of 109
133 | NAD | Undefined behavior not previously listed in subclause G2 | Yes
134 | NAD | What is an 'error number' for strerror? | N/A
135 | NAD | Can the size argument to 'fwrite' be zero? | N/A
136 | NAD | 'mktime' and time gaps | N/A
137 | NAD | 'printf' and negative floating point values | N/A
138 | C89 | Is there an allocated storage duration? | Yes
139 | C89 | Compatibility of complete and incomplete types | Yes
140 | NAD | Behavior of 'setvbuf' | N/A
141 | NAD | What is the meaning of EOF? | N/A
142 | C89 | Reservation of macro names | Yes
143 | C89 | 'fopen' modes | N/A
144 | C89 | Preprocessing of preprocessing directives | Yes
145 | C89 | Constant expressions | Unknown
146 | C89 | Nugatory constraint | Yes
147 | C89 | Sequence points in library functions | Yes
148 | NAD | Defining library functions | Yes
149 | C89 | The term "variable" | Yes
150 | C89 | Initialization of a char array from a string literal | Yes
151 | C89 | Behavior of 'printf' and flags | N/A
152 | NAD | Can you 'longjmp' out of a signal handler? | N/A
153 | Dup | Can 'f()' be considered a call to a function-like macro with one empty argument? | Duplicate of 3
154 | NAD | Consistency of implementation-defined values | Yes
155 | C89 | Zero-sized allocations | N/A
156 | C89 | Closed streams | N/A
157 | C89 | Legitimacy of type synonyms | Yes
158 | C89 | Null pointer conversions | Yes
159 | C89 | Consistency of the C Standard Defects exist in the way the Standard refers to itself | Yes
160 | Open | Reservation of identifiers | Not resolved
161 | NAD | Details of reserved symbols | Yes
162 | C89 | 'gmtime' and 'localtime' | N/A
163 | C89 | Undeclared identifiers | Yes
164 | NAD | Bad declarations | Yes
165 | C89 | Tags and incomplete types | Not resolved
166 | Open | Meaning of lvalue | Not resolved
167 | Open | Consistency of the C Standard (Defect Report UK 015) | Not resolved
168 | Open | Consistency of the C Standard (Defect Report UK 016) | Not resolved
169 | NAD | Trigraphs | Yes
170 | C89 | Operators and punctuators | Not resolved
171 | Open | Ranges of integral types | Not resolved
172 | Open | Relational and equality operators | Not resolved
173 | Open | Line numbers | Not resolved
174 | Open | Implicit conversions | Not resolved
175 | Open | Correction to Technical Corrigendum 1 | Not resolved
176 | Open | Diagnostics for #error | Not resolved
177 | Open | Preprocessing directives | Not resolved
178 | Open | Conformance with array members and allocations | Not resolved
201 | NAD | Integer types longer than long | Yes
202 | C99 | Change return type of certain <fenv.h> functions | N/A
203 | C99 | C locale conflict with ISO/IEC 9945-2 | N/A
204 | C99 | size_t and ptrdiff_t as a long long type | Yes
205 | NAD | New keyword __at_least | Yes
206 | NAD | Default argument conversion of float _Complex | Yes
207 | C99 | Handling of imaginary types | Partial Clang detects use of the _Imaginary keyword but does not otherwise support the type yet.
208 | C99 | Ambiguity in initialization | Yes
209 | C99 | Problem implementing INTN_C macros | Partial Clang provides these definitions in a freestanding compilation, but the type of the value produced by `UINT8_C` and `UINT16_C` is not the type after integer promotion per C99 7.18.4p3.
210 | C99 | 'fprintf' %a and %A conversions recommended practice | N/A
211 | C99 | Accuracy of decimal string to/from "binary" (non-decimal) floating-point conversions | Yes
212 | NAD | Binding of multibyte conversion state objects | N/A
213 | C99 | Lacuna in 'mbrtowc' | N/A
214 | NAD | 'atexit' function registration | N/A
215 | C99 | Equality operators | Yes
216 | C99 | Source character encodings | Yes
217 | NAD | 'asctime' limits | N/A
218 | C99 | Signs of non-numeric floating point values | Yes
219 | NAD | Effective types | Yes
220 | C99 | Definition of "decimal integer" | N/A
221 | NAD | Lacuna in pointer arithmetic | Yes
222 | C99 | Partially initialized structures | Yes
223 | C99 | 'FP_FAST_FMAF' and 'FP_FAST_FMAL' should be integer constant | N/A
224 | C99 | fpclassify return is not defined | N/A
225 | C99 | strtod, strtof and strtold expected form of the subject sequence | N/A
226 | NAD | strftime references | N/A
227 | NAD | strftime %U, %V, and %W conversion specifiers | N/A
228 | C99 | wmemcmp declaration in Annex B | N/A
229 | C99 | localeconv() *_sep_by_space table entries issues | N/A
230 | C99 | Enumerated type rank | Yes
231 | NAD | Semantics of text-line and non-directive | No
232 | C99 | Typo in Annex I | N/A
233 | C99 | %g, %G precision specification | N/A
234 | C99 | Miscellaneous Typos | Yes
235 | C99 | "C" locale collating behaviour not defined | N/A
236 | NAD | The interpretation of type based aliasing rule when applied to union objects or allocated objects | Unknown
237 | NAD | Declarations using [static] | No
238 | C99 | Decriptions of fma() overflow and underflow errors are missing | N/A
239 | C99 | Annex F nexttoward description is inconsistent with 7.12.11.4 and F.9.8.3 | N/A
240 | C99 | lrint, llrint, lround, llround, and ilogb descriptions are not consistent for unrepresentable results | N/A
241 | C99 | Make the base standard and Annex F consistent for pow(0, <0) | N/A
242 | C99 | Make the base standard and Annex F consistent for logb(0) | N/A
243 | C99 | Make the base standard and Annex F consistent for fmod(), remainder(), and remquo() for a zero divisor | N/A
244 | C99 | tgamma(zero or negative integer) should be considered a pole error | N/A
245 | C99 | Missing paragraph numbers | Yes
246 | NAD | Completion of declarators | Yes
247 | C99 | Are values a form of behaviour? | Yes
248 | C99 | Limits are required for optional types | Yes
249 | Dup | Lacuna applying C89:TC1 to C99 | Duplicate of 9
250 | C99 | Non-directives within macro arguments | Yes
251 | C99 | Are struct fred and union fred the same type? | Yes
252 | NAD | Incomplete argument types when calling non-prototyped functions | Yes
253 | NAD | "overriding" in designated initializers | Yes
254 | NAD | mbtowc and partial characters | N/A
255 | NAD | Non-prototyped function calls and argument mismatches | Yes
256 | NAD | Multiple inclusion of headers | N/A
257 | NAD | Common initial sequences and related issues with unions | Unknown
258 | NAD | Ordering of "defined" and macro replacement | Yes
259 | NAD | Macro invocations with no arguments | Yes
260 | NAD | Indeterminate values and identical representations | Unknown
261 | NAD | Constant expressions | Yes
262 | C99 | Maximum size of bit fields | Yes
263 | C99 | All-zero bits representations | Yes
264 | NAD | Graphic characters | N/A
265 | C99 | Preprocessor arithmetic | Yes
266 | NAD | Overflow of sizeof | Yes
267 | C99 | Typos in 5.1.2.3, 7.24.4.4.5, 7.24.6.1, 7.24.6.1 | Yes
268 | C99 | Jumps into iteration statements | Yes
269 | C99 | Lacunae in exact-width integer types | N/A
270 | C99 | wint_t is not the promoted version of wchar_t | N/A
271 | NAD | Lacuna in iswctype and towctrans | N/A
272 | C99 | Type category | Yes
273 | C99 | Meaning of __STDC_ISO_10646__ | Yes The compiler portion of this DR is implemented in Clang, but the `__STDC_ISO_10646__` macro is not defined by Clang; the standard library behavior factors into whether this macro can or cannot be defined.
274 | C99 | Meaning of "character" in <string.h> functions | N/A
275 | C99 | Bitwise-OR of nothing | N/A
276 | C99 | Orientation of perror | N/A
277 | NAD | Declarations within iteration statements | No
278 | C99 | Lacuna in character encodings | Yes
279 | C99 | Wide character code values for members of the basic character set | Yes
280 | NAD | struct tm, member tm_isdst, and mktime() in <time.h> | N/A
281 | C99 | CLOCKS_PER_SEC should not be a constant expression | N/A
282 | C99 | Flexible array members & struct padding | Yes
283 | C99 | Accessing a non-current union member ("type punning") | Unknown
284 | NAD | Does <math.h> define INT_MIN and INT_MAX? | N/A
285 | C99 | Conversion of an imaginary type to _Bool | Partial Clang detects use of the _Imaginary keyword but does not otherwise support the type yet.
286 | C99 | Correctly rounded and rounding direction/mode | N/A
287 | Dup | Floating-point status flags and sequence points | Duplicate of 87
288 | NAD | Deficiency on multibyte conversions | N/A
289 | C99 | Function prototype with [restrict] | Yes
290 | C99 | FLT_EVAL_METHOD and extra precision and/or range | Unknown
291 | C99 | Corrections to requirements on inexact floating-point exceptions | Unknown
292 | C99 | Use of the word variable | Yes
293 | C99 | Typo in Standard - double complex instead of complex in an example | Yes
294 | NAD | Technical question on C99 restrict keyword | Unknown
295 | C99 | Incomplete types for function parameters | Yes
296 | C99 | Is exp(INFINITY) overflow? A range error? A divide-by-zero exception? INFINITY without any errors? | N/A
297 | C99 | May FE_* floating-point exception flags have bits in common? | N/A
298 | C99 | Validity of constant in unsigned long long range | Partial Clang defines the behavior in this situation by automatically using `long long` or `unsigned long long` as the underlying type of the constant; however, Clang fails to diagnose the extension in C89 mode with such constants.
299 | C99 | Is cabs() a type-generic macro? | N/A
300 | NAD | Translation-time expresssion evaluation | Yes
301 | NAD | Meaning of FE_* macros in <fenv.h> | Yes
302 | C99 | 6.10.2p5: Adding underscore to portable include file name character set | Yes
303 | C99 | 6.10p2: Breaking up the very long sentence describing preprocessing directive | Yes
304 | C99 | Clarifying illegal tokens in #if directives | Yes
305 | C99 | 6.10.1p3: Clarifying handling of keywords in #if directives | Yes
306 | C99 | 6.10.3p9: Clarifying that rescanning applies to object-like macros | Yes
307 | C99 | 6.10.3p10: Clarifiying arguments vs. parameters | Yes
308 | C99 | Clarify that source files et al. need not be "files" | Yes
309 | C99 | Clarifying trigraph substitution | Yes
310 | C99 | Add non-corner case example of trigraphs | Yes
311 | C99 | Definition of variably modified types | Yes
312 | C99 | Meaning of "known constant size" | Yes
313 | NAD | Incomplete arrays of VLAs | Yes
314 | NAD | Cross-translation-unit tagged type compatibility | Unknown
315 | C99 | Implementation-defined bit-field types | Yes
316 | NAD | Unprototyped function types | Yes
317 | NAD | Function definitions with empty parentheses | Yes
318 | C99 | (double)0.1f with FLT_EVAL_METHOD being 2 | Unknown
319 | NAD | printf("%a", 1.0) and trailing zeros | N/A
320 | C99 | Scope of variably modified type | Yes
321 | C99 | Wide character code values for members of the basic character set | Yes
322 | C99 | Problem with TC2 Change #67 (Add perror to the list defining byte input/output functions) | N/A
323 | C99 | Potential problems with TC2 #34, #35, and #36 | N/A
324 | C99 | Tokenization obscurities | Yes
325 | NAD | strerror() | N/A
326 | C99 | asctime() | N/A
327 | C99 | Italicize definition of variable length array type, add forward references | Yes
328 | C99 | String literals in compound literal initialization | Partial Clang properly implements the use of string literals in a compound literal initializer, but fails to diagnose use of a variably-modified type at file scope. DR339 (about variably-modified types) is marked as a duplicate of DR328.
329 | C99 | Math functions and directed rounding | N/A
330 | C99 | Externally visible exceptional conditions | N/A
331 | NAD | permit FE_DIVBYZERO when errno says EDOM | N/A
332 | C99 | gets is generally unsafe | N/A
333 | C99 | Missing Predefined Macro Name | Yes
334 | Open | Missing semantics of comparison macros | Not resolved
335 | NAD | _Bool bit-fields | Yes
336 | C99 | What does TMP_MAX actually indicate? | N/A
337 | C99 | stdio.h macro definition problems | N/A
338 | C99 | C99 seems to exclude indeterminate value from being an uninitialized register | Yes
339 | Dup | Variably modified compound literal | Duplicate of 328
340 | C99 | Composite types for variable-length arrays | Yes
341 | C99 | [*] in abstract declarators | Yes
342 | Dup | VLAs and conditional expressions | Duplicate of 340
343 | C99 | Initializing qualified wchar_t arrays | Yes
344 | C99 | Casts in preprocessor conditional expressions | Yes
345 | C99 | Where does parameter scope start? | Yes
400 | C11 | realloc with size zero problems | Unknown
401 | C11 | "happens before" can not be cyclic | Yes
402 | C11 | Memory model coherence is not aligned with C++11 | Yes
403 | C11 | malloc() and free() in the memory model | N/A
404 | C11 | Joke fragment remains in a footnote | Yes
405 | C11 | The mutex specification | N/A
406 | C11 | Visible sequences of side effects are redundant | Yes
407 | C11 | Memory ordering of atomics | Unknown
408 | NAD | Should locks provide intra-thread synchronization | N/A
409 | C11 | f(inf) is inf being a range error | N/A
410 | C11 | ilogb inconsistent with lrint, lround | N/A
411 | C11 | Predefined macro values | Yes
412 | C11 | #elif | Yes
413 | NAD | Initialization | Yes
414 | C11 | Typos in 6.27 Threads <threads.h> | N/A
415 | C11 | Missing divide by zero entry in Annex J | Yes
416 | C11 | tss_t destruction unspecified | N/A
417 | C11 | Annex J not updated with necessary aligned_alloc entries | Yes
418 | NAD | Possible defect report: fmod(0.,NaN) and fmod(NaN,infinity) | N/A
419 | C11 | Generic Functions | Yes
420 | NAD | Sytax error in specification of for-statement | Yes
421 | NAD | Initialization of atomic_flag | N/A
422 | NAD | Initialization of atomic types | N/A
423 | C11 | Defect Report relative to n1570: underspecification for qualified rvalues | Partial Clang properly handles dropping qualifiers from cast operations, but does not yet handle dropping qualifiers from the function return type.
424 | Dup | Underspecification of tss_t | Duplicate of 416
425 | NAD | No specification for the access to variables with temporary lifetime | Yes
426 | C11 | G.5.1: -yv and -x/v are ambiguous | N/A
427 | NAD | Function Parameter and Return Value Assignments | Unknown
428 | C11 | Runtime-constraint issue with sprintf family of routines in Annex K | N/A
429 | C11 | Should gets_s discard next input line when (s == NULL) ? | N/A
430 | C11 | getenv_s, maxsize should be allowed to be zero | N/A
431 | C11 | atomic_compare_exchange: What does it mean to say two structs compare equal? | Unknown
432 | C11 | Possible defect report: Is 0.0 required to be a representable value? | Yes
433 | C11 | Issue with constraints for wide character function arguments involving RSIZE_MAX | N/A
434 | C11 | Possible defect report: Missing constraint w.r.t. Atomic | Yes
435 | NAD | Possible defect report: Missing constraint w.r.t. Imaginary | Yes
436 | C11 | Request for interpretation of C11 6.8.5#6 | Yes
437 | C11 | clock overflow problems | N/A
438 | C11 | ungetc / ungetwc and file position after discarding push back problems | N/A
439 | C11 | Issues with the definition of "full expression" | Unknown
440 | NAD | Floating-point issues in C11 from PDTS 18661-1 UK review, Issue 1 | Unknown
441 | C11 | Floating-point issues in C11 from PDTS 18661-1 UK review, Issue 2 | N/A
442 | NAD | Floating-point issues in C11 from PDTS 18661-1 UK review, Issue 3 | Unknown
443 | NAD | Floating-point issues in C11 from PDTS 18661-1 UK review, Issue 4 | Unknown
444 | C11 | Issues with alignment in C11, part 1 | Partial Clang rejects use of an alignment specifier in a compound literal expression.
445 | C11 | Issues with alignment in C11, part 2 | Unknown
446 | NAD | Use byte instead of character for memcmp, memcpy | N/A
447 | C11 | Boolean from complex | Yes
448 | C11 | What are the semantics of a # non-directive? | Yes
449 | NAD | What is the value of TSS_DTOR_ITERATIONS for implementations with no maximum? | N/A
450 | C11 | tmpnam_s clears s[0] when maxsize > RSIZE_MAX | N/A
451 | NAD | Instability of uninitialized automatic variables | Unknown
452 | C11 | Effective Type in Loop Invariant | Unknown
453 | C11 | Atomic flag type and operations | N/A
454 | NAD | ATOMIC_VAR_INIT (issues 3 and 4) | Yes
455 | NAD | ATOMIC_VAR_INIT issue 5 | Yes
456 | Dup | Compile time definition of UINTN_C(value) | Duplicate of 209
457 | C11 | The ctime_s function in Annex K defined incorrectly | N/A
458 | C11 | ATOMIC_XXX_LOCK_FREE macros not constant expressions | N/A
459 | C11 | atomic_load missing const qualifier | Yes
460 | C11 | aligned_alloc underspecified | N/A
461 | NAD | Problems with references to objects in signal handlers | N/A
462 | C11 | Clarifying objects accessed in signal handlers | N/A
463 | NAD | Left-shifting into the sign bit | Yes
464 | C11 | Clarifying the Behavior of the #line Directive | Yes
465 | C11 | Fixing an inconsistency in atomic_is_lock_free | Unknown
466 | NAD | Scope of a for loop control declaration | Yes
467 | C11 | Maximum representable finite description vs math | Unknown
468 | C11 | strncpy_s clobbers buffer past null | N/A
469 | NAD | Lock ownership vs. thread termination | N/A
470 | C11 | mtx_trylock should be allowed to fail spuriously | N/A
471 | C11 | Complex math functions cacosh and ctanh | N/A
472 | C11 | Introduction to complex arithmetic in 7.3.1p3 wrong due to CMPLX | N/A
473 | C11 | "A range error occurs if x is too large." is misleading | N/A
474 | NAD | NOTE 1 Clarification for atomic_compare_exchange | N/A
475 | C11 | Misleading Atomic library references to atomic types | Yes
476 | C11 | volatile semantics for lvalues | Unknown
477 | C11 | nan should take a string argument | N/A
478 | NAD | Valid uses of the main function | Yes
479 | Dup | Unclear specification of mtx_trylock on non-recursive muteness | Duplicate of 269
480 | C11 | cnd_wait and cnd_timewait should allow spurious wake-ups | N/A
481 | C11 | Controlling expression of _Generic primary expression | Clang 3.8
482 | NAD | Macro invocation split over many files | Unknown
483 | NAD | __LINE__ and __FILE__ in macro replacement list | Yes
484 | NAD | invalid characters in strcoll() | N/A
485 | C11 | Problem with the specification of ATOMIC_VAR_INIT | Yes
486 | NAD | Inconsistent specification for arithmetic on atomic objects | Unknown
487 | C11 | timespec vs. tm | N/A
488 | C11 | c16rtomb() on wide characters encoded as multiple char16_t | N/A
489 | NAD | Integer Constant Expression | Partial Clang inconsistently diagnoses folding a constan expression into an ICE as an extension.
490 | NAD | Unwritten Assumptions About if-then | Yes
491 | C11 | Concern with Keywords that Match Reserved Identifiers | Partial Clang issues a reserved identifier diagnostic when the identifier leads with an underscore followed by a capital letter or double underscores, even if the identifier is used for a macro definition.
492 | NAD | Named Child struct-union with no Member | Clang 3.6
493 | Dup | Mutex Initialization Underspecified | Duplicate of 469
494 | C11 | Part 1: Alignment specifier expression evaluation | Yes
495 | C11 | Part 2: Atomic specifier expression evaluation | Not resolved
496 | NAD | offsetof questions | Yes
497 | C11 | "white-space character" defined in two places | N/A
498 | C11 | mblen, mbtowc, and wctomb thread-safety | N/A
499 | C17 | Anonymous structure in union behavior | Yes
500 | C17 | Ambiguous specification for FLT_EVAL_METHOD | Unknown
501 | C17 | Can DECIMAL_DIG be larger than necessary? | N/A
502 | NAD | Flexible array member in an anonymous struct | Yes
503 | NAD | Hexadecimal floating-point and strtod | N/A