1 // RUN: %clang_cc1 -std=c++11 -fsyntax-only -triple %itanium_abi_triple -verify -Wreinterpret-base-class -Wno-unused-volatile-lvalue %s
2 // RUN: %clang_cc1 -std=c++11 -fsyntax-only -triple %ms_abi_triple -DMSABI -verify -Wreinterpret-base-class -Wno-unused-volatile-lvalue %s
3
4 // RUN: not %clang_cc1 -std=c++11 -fsyntax-only -triple %itanium_abi_triple -fdiagnostics-parseable-fixits -Wreinterpret-base-class -Wno-unused-volatile-lvalue %s 2>&1 | FileCheck %s
5 // RUN: not %clang_cc1 -std=c++11 -fsyntax-only -triple %ms_abi_triple -fdiagnostics-parseable-fixits -Wreinterpret-base-class -Wno-unused-volatile-lvalue %s 2>&1 | FileCheck %s
6
7 // PR 13824
8 class A {
9 };
10 class DA : public A {
11 };
12 class DDA : public DA {
13 };
14 class DAo : protected A {
15 };
16 class DAi : private A {
17 };
18
19 class DVA : public virtual A {
20 };
21 class DDVA : public virtual DA {
22 };
23 class DMA : public virtual A, public virtual DA {
24 };
25
26 class B;
27
28 struct C {
29 // Do not fail on incompletely-defined classes.
30 decltype(reinterpret_cast<C *>(0)) foo;
31 decltype(reinterpret_cast<A *>((C *) 0)) bar;
32 decltype(reinterpret_cast<C *>((A *) 0)) baz;
33 };
34
reinterpret_not_defined_class(B * b,C * c)35 void reinterpret_not_defined_class(B *b, C *c) {
36 // Should not fail if class has no definition.
37 (void)*reinterpret_cast<C *>(b);
38 (void)*reinterpret_cast<B *>(c);
39
40 (void)reinterpret_cast<C &>(*b);
41 (void)reinterpret_cast<B &>(*c);
42 }
43
44 // Do not fail on erroneous classes with fields of incompletely-defined types.
45 // Base class is malformed.
46 namespace BaseMalformed {
47 struct A; // expected-note {{forward declaration of 'BaseMalformed::A'}}
48 struct B {
49 A a; // expected-error {{field has incomplete type 'BaseMalformed::A'}}
50 };
51 struct C : public B {} c;
52 B *b = reinterpret_cast<B *>(&c);
53 } // end anonymous namespace
54
55 // Child class is malformed.
56 namespace ChildMalformed {
57 struct A; // expected-note {{forward declaration of 'ChildMalformed::A'}}
58 struct B {};
59 struct C : public B {
60 A a; // expected-error {{field has incomplete type 'ChildMalformed::A'}}
61 } c;
62 B *b = reinterpret_cast<B *>(&c);
63 } // end anonymous namespace
64
65 // Base class outside upcast base-chain is malformed.
66 namespace BaseBaseMalformed {
67 struct A; // expected-note {{forward declaration of 'BaseBaseMalformed::A'}}
68 struct Y {};
69 struct X { A a; }; // expected-error {{field has incomplete type 'BaseBaseMalformed::A'}}
70 struct B : Y, X {};
71 struct C : B {} c;
72 B *p = reinterpret_cast<B*>(&c);
73 }
74
75 namespace InheritanceMalformed {
76 struct A; // expected-note {{forward declaration of 'InheritanceMalformed::A'}}
77 struct B : A {}; // expected-error {{base class has incomplete type}}
78 struct C : B {} c;
79 B *p = reinterpret_cast<B*>(&c);
80 }
81
82 // Virtual base class outside upcast base-chain is malformed.
83 namespace VBaseMalformed{
84 struct A; // expected-note {{forward declaration of 'VBaseMalformed::A'}}
85 struct X { A a; }; // expected-error {{field has incomplete type 'VBaseMalformed::A'}}
86 struct B : public virtual X {};
87 struct C : B {} c;
88 B *p = reinterpret_cast<B*>(&c);
89 }
90
reinterpret_not_updowncast(A * pa,const A * pca,A & a,const A & ca)91 void reinterpret_not_updowncast(A *pa, const A *pca, A &a, const A &ca) {
92 (void)*reinterpret_cast<C *>(pa);
93 (void)*reinterpret_cast<const C *>(pa);
94 (void)*reinterpret_cast<volatile C *>(pa);
95 (void)*reinterpret_cast<const volatile C *>(pa);
96
97 (void)*reinterpret_cast<const C *>(pca);
98 (void)*reinterpret_cast<const volatile C *>(pca);
99
100 (void)reinterpret_cast<C &>(a);
101 (void)reinterpret_cast<const C &>(a);
102 (void)reinterpret_cast<volatile C &>(a);
103 (void)reinterpret_cast<const volatile C &>(a);
104
105 (void)reinterpret_cast<const C &>(ca);
106 (void)reinterpret_cast<const volatile C &>(ca);
107 }
108
reinterpret_pointer_downcast(A * a,const A * ca)109 void reinterpret_pointer_downcast(A *a, const A *ca) {
110 (void)*reinterpret_cast<DA *>(a);
111 (void)*reinterpret_cast<const DA *>(a);
112 (void)*reinterpret_cast<volatile DA *>(a);
113 (void)*reinterpret_cast<const volatile DA *>(a);
114
115 (void)*reinterpret_cast<const DA *>(ca);
116 (void)*reinterpret_cast<const volatile DA *>(ca);
117
118 (void)*reinterpret_cast<DDA *>(a);
119 (void)*reinterpret_cast<DAo *>(a);
120 (void)*reinterpret_cast<DAi *>(a);
121 // expected-warning@+2 {{'reinterpret_cast' to class 'DVA *' from its virtual base 'A *' behaves differently from 'static_cast'}}
122 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
123 (void)*reinterpret_cast<DVA *>(a);
124 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:10-[[@LINE-1]]:26}:"static_cast"
125
126 // expected-warning@+2 {{'reinterpret_cast' to class 'DDVA *' from its virtual base 'A *' behaves differently from 'static_cast'}}
127 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
128 (void)*reinterpret_cast<DDVA *>(a);
129 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:10-[[@LINE-1]]:26}:"static_cast"
130
131 // expected-warning@+2 {{'reinterpret_cast' to class 'DMA *' from its virtual base 'A *' behaves differently from 'static_cast'}}
132 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
133 (void)*reinterpret_cast<DMA *>(a);
134 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:10-[[@LINE-1]]:26}:"static_cast"
135 }
136
reinterpret_reference_downcast(A a,A & ra,const A & cra)137 void reinterpret_reference_downcast(A a, A &ra, const A &cra) {
138 (void)reinterpret_cast<DA &>(a);
139 (void)reinterpret_cast<const DA &>(a);
140 (void)reinterpret_cast<volatile DA &>(a);
141 (void)reinterpret_cast<const volatile DA &>(a);
142
143 (void)reinterpret_cast<DA &>(ra);
144 (void)reinterpret_cast<const DA &>(ra);
145 (void)reinterpret_cast<volatile DA &>(ra);
146 (void)reinterpret_cast<const volatile DA &>(ra);
147
148 (void)reinterpret_cast<const DA &>(cra);
149 (void)reinterpret_cast<const volatile DA &>(cra);
150
151 (void)reinterpret_cast<DDA &>(a);
152 (void)reinterpret_cast<DAo &>(a);
153 (void)reinterpret_cast<DAi &>(a);
154 // expected-warning@+2 {{'reinterpret_cast' to class 'DVA &' from its virtual base 'A' behaves differently from 'static_cast'}}
155 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
156 (void)reinterpret_cast<DVA &>(a);
157 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
158
159 // expected-warning@+2 {{'reinterpret_cast' to class 'DDVA &' from its virtual base 'A' behaves differently from 'static_cast'}}
160 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
161 (void)reinterpret_cast<DDVA &>(a);
162 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
163
164 // expected-warning@+2 {{'reinterpret_cast' to class 'DMA &' from its virtual base 'A' behaves differently from 'static_cast'}}
165 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
166 (void)reinterpret_cast<DMA &>(a);
167 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
168 }
169
reinterpret_pointer_upcast(DA * da,const DA * cda,DDA * dda,DAo * dao,DAi * dai,DVA * dva,DDVA * ddva,DMA * dma)170 void reinterpret_pointer_upcast(DA *da, const DA *cda, DDA *dda, DAo *dao,
171 DAi *dai, DVA *dva, DDVA *ddva, DMA *dma) {
172 (void)*reinterpret_cast<A *>(da);
173 (void)*reinterpret_cast<const A *>(da);
174 (void)*reinterpret_cast<volatile A *>(da);
175 (void)*reinterpret_cast<const volatile A *>(da);
176
177 (void)*reinterpret_cast<const A *>(cda);
178 (void)*reinterpret_cast<const volatile A *>(cda);
179
180 (void)*reinterpret_cast<A *>(dda);
181 (void)*reinterpret_cast<DA *>(dda);
182 (void)*reinterpret_cast<A *>(dao);
183 (void)*reinterpret_cast<A *>(dai);
184 // expected-warning@+2 {{'reinterpret_cast' from class 'DVA *' to its virtual base 'A *' behaves differently from 'static_cast'}}
185 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
186 (void)*reinterpret_cast<A *>(dva);
187 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:10-[[@LINE-1]]:26}:"static_cast"
188
189 // expected-warning@+2 {{'reinterpret_cast' from class 'DDVA *' to its virtual base 'A *' behaves differently from 'static_cast'}}
190 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
191 (void)*reinterpret_cast<A *>(ddva);
192 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:10-[[@LINE-1]]:26}:"static_cast"
193
194 // expected-warning@+2 {{'reinterpret_cast' from class 'DDVA *' to its virtual base 'DA *' behaves differently from 'static_cast'}}
195 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
196 (void)*reinterpret_cast<DA *>(ddva);
197 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:10-[[@LINE-1]]:26}:"static_cast"
198
199 // expected-warning@+2 {{'reinterpret_cast' from class 'DMA *' to its virtual base 'A *' behaves differently from 'static_cast'}}
200 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
201 (void)*reinterpret_cast<A *>(dma);
202 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:10-[[@LINE-1]]:26}:"static_cast"
203
204 // expected-warning@+2 {{'reinterpret_cast' from class 'DMA *' to its virtual base 'DA *' behaves differently from 'static_cast'}}
205 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
206 (void)*reinterpret_cast<DA *>(dma);
207 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:10-[[@LINE-1]]:26}:"static_cast"
208 }
209
reinterpret_reference_upcast(DA & da,const DA & cda,DDA & dda,DAo & dao,DAi & dai,DVA & dva,DDVA & ddva,DMA & dma)210 void reinterpret_reference_upcast(DA &da, const DA &cda, DDA &dda, DAo &dao,
211 DAi &dai, DVA &dva, DDVA &ddva, DMA &dma) {
212 (void)reinterpret_cast<A &>(da);
213 (void)reinterpret_cast<const A &>(da);
214 (void)reinterpret_cast<volatile A &>(da);
215 (void)reinterpret_cast<const volatile A &>(da);
216
217 (void)reinterpret_cast<const A &>(cda);
218 (void)reinterpret_cast<const volatile A &>(cda);
219
220 (void)reinterpret_cast<A &>(dda);
221 (void)reinterpret_cast<DA &>(dda);
222 (void)reinterpret_cast<A &>(dao);
223 (void)reinterpret_cast<A &>(dai);
224 // expected-warning@+2 {{'reinterpret_cast' from class 'DVA' to its virtual base 'A &' behaves differently from 'static_cast'}}
225 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
226 (void)reinterpret_cast<A &>(dva);
227 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
228
229 // expected-warning@+2 {{'reinterpret_cast' from class 'DDVA' to its virtual base 'A &' behaves differently from 'static_cast'}}
230 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
231 (void)reinterpret_cast<A &>(ddva);
232 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
233
234 // expected-warning@+2 {{'reinterpret_cast' from class 'DDVA' to its virtual base 'DA &' behaves differently from 'static_cast'}}
235 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
236 (void)reinterpret_cast<DA &>(ddva);
237 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
238
239 // expected-warning@+2 {{'reinterpret_cast' from class 'DMA' to its virtual base 'A &' behaves differently from 'static_cast'}}
240 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
241 (void)reinterpret_cast<A &>(dma);
242 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
243
244 // expected-warning@+2 {{'reinterpret_cast' from class 'DMA' to its virtual base 'DA &' behaves differently from 'static_cast'}}
245 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
246 (void)reinterpret_cast<DA &>(dma);
247 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
248 }
249
250 struct E {
251 int x;
252 };
253
254 class F : public E {
foo()255 virtual int foo() { return x; }
256 };
257
258 class G : public F {
259 };
260
261 class H : public E, public A {
262 };
263
264 class I : virtual public F {
265 };
266
267 typedef const F * K;
268 typedef volatile K L;
269
different_subobject_downcast(E * e,F * f,A * a)270 void different_subobject_downcast(E *e, F *f, A *a) {
271 // expected-warning@+2 {{'reinterpret_cast' to class 'F *' from its base at non-zero offset 'E *' behaves differently from 'static_cast'}}
272 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
273 (void)reinterpret_cast<F *>(e);
274 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
275
276 // expected-warning@+2 {{'reinterpret_cast' to class 'G *' from its base at non-zero offset 'E *' behaves differently from 'static_cast'}}
277 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
278 (void)reinterpret_cast<G *>(e);
279 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
280
281 (void)reinterpret_cast<H *>(e);
282 // expected-warning@+2 {{'reinterpret_cast' to class 'I *' from its virtual base 'E *' behaves differently from 'static_cast'}}
283 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
284 (void)reinterpret_cast<I *>(e);
285 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
286
287
288 (void)reinterpret_cast<G *>(f);
289 // expected-warning@+2 {{'reinterpret_cast' to class 'I *' from its virtual base 'F *' behaves differently from 'static_cast'}}
290 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
291 (void)reinterpret_cast<I *>(f);
292 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
293
294 #ifdef MSABI
295 // In MS ABI mode, A is at non-zero offset in H.
296 // expected-warning@+3 {{'reinterpret_cast' to class 'H *' from its base at non-zero offset 'A *' behaves differently from 'static_cast'}}
297 // expected-note@+2 {{use 'static_cast'}}
298 #endif
299 (void)reinterpret_cast<H *>(a);
300
301 // expected-warning@+2 {{'reinterpret_cast' to class 'L' (aka 'const F *volatile') from its base at non-zero offset 'E *' behaves differently from 'static_cast'}}
302 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while downcasting}}
303 (void)reinterpret_cast<L>(e);
304 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
305 }
306
different_subobject_upcast(F * f,G * g,H * h,I * i)307 void different_subobject_upcast(F *f, G *g, H *h, I *i) {
308 // expected-warning@+2 {{'reinterpret_cast' from class 'F *' to its base at non-zero offset 'E *' behaves differently from 'static_cast'}}
309 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
310 (void)reinterpret_cast<E *>(f);
311 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
312
313 (void)reinterpret_cast<F *>(g);
314 // expected-warning@+2 {{'reinterpret_cast' from class 'G *' to its base at non-zero offset 'E *' behaves differently from 'static_cast'}}
315 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
316 (void)reinterpret_cast<E *>(g);
317 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
318
319 (void)reinterpret_cast<E *>(h);
320
321 #ifdef MSABI
322 // In MS ABI mode, A is at non-zero offset in H.
323 // expected-warning@+3 {{'reinterpret_cast' from class 'H *' to its base at non-zero offset 'A *' behaves differently from 'static_cast'}}
324 // expected-note@+2 {{use 'static_cast'}}
325 #endif
326 (void)reinterpret_cast<A *>(h);
327
328 // expected-warning@+2 {{'reinterpret_cast' from class 'I *' to its virtual base 'F *' behaves differently from 'static_cast'}}
329 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
330 (void)reinterpret_cast<F *>(i);
331 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
332
333 // expected-warning@+2 {{'reinterpret_cast' from class 'I *' to its virtual base 'E *' behaves differently from 'static_cast'}}
334 // expected-note@+1 {{use 'static_cast' to adjust the pointer correctly while upcasting}}
335 (void)reinterpret_cast<E *>(i);
336 // CHECK: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:25}:"static_cast"
337 }
338