clang/test/CodeGenCXX/wasm-eh.cpp

   1 // REQUIRES: webassembly-registered-target
   2
   3 // RUN: %clang -E -dM %s -target wasm32-unknown-unknown -fwasm-exceptions | FileCheck %s -check-prefix PREPROCESSOR
   4 // PREPROCESSOR: #define __WASM_EXCEPTIONS__ 1
   5
   6 // RUN: %clang_cc1 %s -triple wasm32-unknown-unknown -fms-extensions -fexceptions -fcxx-exceptions -mllvm -wasm-enable-eh -exception-model=wasm -target-feature +exception-handling -emit-llvm -o - -std=c++11 | FileCheck %s
   7 // RUN: %clang_cc1 %s -triple wasm64-unknown-unknown -fms-extensions -fexceptions -fcxx-exceptions -mllvm -wasm-enable-eh -exception-model=wasm -target-feature +exception-handling -emit-llvm -o - -std=c++11 | FileCheck %s
   8
   9 void may_throw();
  10 void dont_throw() noexcept;
  11
  12 struct Cleanup {
  13   ~Cleanup() { dont_throw(); }
  14 };
  15
  16 // Multiple catch clauses w/o catch-all
  17 void test0() {
  18   try {
  19     may_throw();
  20   } catch (int) {
  21     dont_throw();
  22   } catch (double) {
  23     dont_throw();
  24   }
  25 }
  26
  27 // CHECK-LABEL: define void @_Z5test0v() {{.*}} personality ptr @__gxx_wasm_personality_v0
  28
  29 // CHECK:   %[[INT_ALLOCA:.*]] = alloca i32
  30 // CHECK:   invoke void @_Z9may_throwv()
  31 // CHECK-NEXT:           to label %[[NORMAL_BB:.*]] unwind label %[[CATCHDISPATCH_BB:.*]]
  32
  33 // CHECK: [[CATCHDISPATCH_BB]]:
  34 // CHECK-NEXT:   %[[CATCHSWITCH:.*]] = catchswitch within none [label %[[CATCHSTART_BB:.*]]] unwind to caller
  35
  36 // CHECK: [[CATCHSTART_BB]]:
  37 // CHECK-NEXT:   %[[CATCHPAD:.*]] = catchpad within %[[CATCHSWITCH]] [ptr @_ZTIi, ptr @_ZTId]
  38 // CHECK-NEXT:   %[[EXN:.*]] = call ptr @llvm.wasm.get.exception(token %[[CATCHPAD]])
  39 // CHECK-NEXT:   store ptr %[[EXN]], ptr %exn.slot
  40 // CHECK-NEXT:   %[[SELECTOR:.*]] = call i32 @llvm.wasm.get.ehselector(token %[[CATCHPAD]])
  41 // CHECK-NEXT:   %[[TYPEID:.*]] = call i32 @llvm.eh.typeid.for.p0(ptr @_ZTIi) #7
  42 // CHECK-NEXT:   %[[MATCHES:.*]] = icmp eq i32 %[[SELECTOR]], %[[TYPEID]]
  43 // CHECK-NEXT:   br i1 %[[MATCHES]], label %[[CATCH_INT_BB:.*]], label %[[CATCH_FALLTHROUGH_BB:.*]]
  44
  45 // CHECK: [[CATCH_INT_BB]]:
  46 // CHECK-NEXT:   %[[EXN:.*]] = load ptr, ptr %exn.slot
  47 // CHECK-NEXT:   %[[ADDR:.*]] = call ptr @__cxa_begin_catch(ptr %[[EXN]]) {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
  48 // CHECK-NEXT:   %[[INT_VAL:.*]] = load i32, ptr %[[ADDR]]
  49 // CHECK-NEXT:   store i32 %[[INT_VAL]], ptr %[[INT_ALLOCA]]
  50 // CHECK-NEXT:   call void @_Z10dont_throwv() {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
  51 // CHECK-NEXT:   call void @__cxa_end_catch() {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
  52 // CHECK-NEXT:   catchret from %[[CATCHPAD]] to label %[[CATCHRET_DEST_BB0:.*]]
  53
  54 // CHECK: [[CATCHRET_DEST_BB0]]:
  55 // CHECK-NEXT:   br label %[[TRY_CONT_BB:.*]]
  56
  57 // CHECK: [[CATCH_FALLTHROUGH_BB]]
  58 // CHECK-NEXT:   %[[TYPEID:.*]] = call i32 @llvm.eh.typeid.for.p0(ptr @_ZTId) #7
  59 // CHECK-NEXT:   %[[MATCHES:.*]] = icmp eq i32 %[[SELECTOR]], %[[TYPEID]]
  60 // CHECK-NEXT:   br i1 %[[MATCHES]], label %[[CATCH_FLOAT_BB:.*]], label %[[RETHROW_BB:.*]]
  61
  62 // CHECK: [[CATCH_FLOAT_BB]]:
  63 // CHECK:   catchret from %[[CATCHPAD]] to label %[[CATCHRET_DEST_BB1:.*]]
  64
  65 // CHECK: [[CATCHRET_DEST_BB1]]:
  66 // CHECK-NEXT:   br label %[[TRY_CONT_BB]]
  67
  68 // CHECK: [[RETHROW_BB]]:
  69 // CHECK-NEXT:   call void @llvm.wasm.rethrow() {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
  70 // CHECK-NEXT:   unreachable
  71
  72 // Single catch-all
  73 void test1() {
  74   try {
  75     may_throw();
  76   } catch (...) {
  77     dont_throw();
  78   }
  79 }
  80
  81 // CATCH-LABEL: @_Z5test1v()
  82
  83 // CHECK:   %[[CATCHSWITCH:.*]] = catchswitch within none [label %[[CATCHSTART_BB:.*]]] unwind to caller
  84
  85 // CHECK: [[CATCHSTART_BB]]:
  86 // CHECK-NEXT:   %[[CATCHPAD:.*]] = catchpad within %[[CATCHSWITCH]] [ptr null]
  87 // CHECK:   br label %[[CATCH_ALL_BB:.*]]
  88
  89 // CHECK: [[CATCH_ALL_BB]]:
  90 // CHECK:   catchret from %[[CATCHPAD]] to label
  91
  92 // Multiple catch clauses w/ catch-all
  93 void test2() {
  94   try {
  95     may_throw();
  96   } catch (int) {
  97     dont_throw();
  98   } catch (...) {
  99     dont_throw();
 100   }
 101 }
 102
 103 // CHECK-LABEL: @_Z5test2v()
 104
 105 // CHECK:   %[[CATCHSWITCH:.*]] = catchswitch within none [label %[[CATCHSTART_BB:.*]]] unwind to caller
 106
 107 // CHECK: [[CATCHSTART_BB]]:
 108 // CHECK-NEXT:   %[[CATCHPAD:.*]] = catchpad within %[[CATCHSWITCH]] [ptr @_ZTIi, ptr null]
 109 // CHECK:   br i1 %{{.*}}, label %[[CATCH_INT_BB:.*]], label %[[CATCH_ALL_BB:.*]]
 110
 111 // CHECK: [[CATCH_INT_BB]]:
 112 // CHECK:   catchret from %[[CATCHPAD]] to label
 113
 114 // CHECK: [[CATCH_ALL_BB]]:
 115 // CHECK:   catchret from %[[CATCHPAD]] to label
 116
 117 // Cleanup
 118 void test3() {
 119   Cleanup c;
 120   may_throw();
 121 }
 122
 123 // CHECK-LABEL: @_Z5test3v()
 124
 125 // CHECK:   invoke void @_Z9may_throwv()
 126 // CHECK-NEXT:           to label {{.*}} unwind label %[[EHCLEANUP_BB:.*]]
 127
 128 // CHECK: [[EHCLEANUP_BB]]:
 129 // CHECK-NEXT:   %[[CLEANUPPAD:.*]] = cleanuppad within none []
 130 // CHECK-NEXT:   call noundef ptr @_ZN7CleanupD1Ev(ptr {{[^,]*}} %{{.*}}) {{.*}} [ "funclet"(token %[[CLEANUPPAD]]) ]
 131 // CHECK-NEXT:   cleanupret from %[[CLEANUPPAD]] unwind to caller
 132
 133 // Possibly throwing function call within a catch
 134 void test4() {
 135   try {
 136     may_throw();
 137   } catch (int) {
 138     may_throw();
 139   }
 140 }
 141
 142 // CHECK-LABEL: @_Z5test4v()
 143
 144 // CHECK:   %[[CATCHSWITCH]] = catchswitch within none [label %[[CATCHSTART_BB]]] unwind to caller
 145
 146 // CHECK: [[CATCHSTART_BB]]:
 147 // CHECK:   %[[CATCHPAD:.*]] = catchpad within %[[CATCHSWITCH]] [ptr @_ZTIi]
 148
 149 // CHECK:   invoke void @_Z9may_throwv() [ "funclet"(token %[[CATCHPAD]]) ]
 150 // CHECK-NEXT:           to label %[[INVOKE_CONT_BB:.*]] unwind label %[[EHCLEANUP_BB:.*]]
 151
 152 // CHECK: [[INVOKE_CONT_BB]]:
 153 // CHECK-NEXT:   call void @__cxa_end_catch() {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
 154 // CHECK-NEXT:   catchret from %[[CATCHPAD]] to label
 155
 156 // CHECK: [[EHCLEANUP_BB]]:
 157 // CHECK-NEXT:   %[[CLEANUPPAD:.*]] = cleanuppad within %[[CATCHPAD]] []
 158 // CHECK-NEXT:   call void @__cxa_end_catch() {{.*}} [ "funclet"(token %[[CLEANUPPAD]]) ]
 159 // CHECK-NEXT:   cleanupret from %[[CLEANUPPAD]] unwind to caller
 160
 161 // Possibly throwing function call within a catch-all
 162 void test5() {
 163   try {
 164     may_throw();
 165   } catch (...) {
 166     may_throw();
 167   }
 168 }
 169
 170 // CHECK-LABEL: @_Z5test5v()
 171
 172 // CHECK:   %[[CATCHSWITCH:.*]] = catchswitch within none [label %[[CATCHSTART_BB]]] unwind to caller
 173
 174 // CHECK: [[CATCHSTART_BB]]:
 175 // CHECK:   %[[CATCHPAD:.*]] = catchpad within %[[CATCHSWITCH]] [ptr null]
 176
 177 // CHECK:   invoke void @_Z9may_throwv() [ "funclet"(token %[[CATCHPAD]]) ]
 178 // CHECK-NEXT:           to label %[[INVOKE_CONT_BB0:.*]] unwind label %[[EHCLEANUP_BB:.*]]
 179
 180 // CHECK: [[INVOKE_CONT_BB0]]:
 181 // CHECK-NEXT:   call void @__cxa_end_catch() [ "funclet"(token %[[CATCHPAD]]) ]
 182 // CHECK-NEXT:   catchret from %[[CATCHPAD]] to label
 183
 184 // CHECK: [[EHCLEANUP_BB]]:
 185 // CHECK-NEXT:   %[[CLEANUPPAD0:.*]] = cleanuppad within %[[CATCHPAD]] []
 186 // CHECK-NEXT:   invoke void @__cxa_end_catch() [ "funclet"(token %[[CLEANUPPAD0]]) ]
 187 // CHECK-NEXT:           to label %[[INVOKE_CONT_BB1:.*]] unwind label %[[TERMINATE_BB:.*]]
 188
 189 // CHECK: [[INVOKE_CONT_BB1]]:
 190 // CHECK-NEXT:   cleanupret from %[[CLEANUPPAD0]] unwind to caller
 191
 192 // CHECK: [[TERMINATE_BB]]:
 193 // CHECK-NEXT:   %[[CLEANUPPAD1:.*]] = cleanuppad within %[[CLEANUPPAD0]] []
 194 // CHECK-NEXT:   call void @_ZSt9terminatev() {{.*}} [ "funclet"(token %[[CLEANUPPAD1]]) ]
 195 // CHECK-NEXT:   unreachable
 196
 197 // Try-catch with cleanups
 198 void test6() {
 199   Cleanup c1;
 200   try {
 201     Cleanup c2;
 202     may_throw();
 203   } catch (int) {
 204     Cleanup c3;
 205     may_throw();
 206   }
 207 }
 208
 209 // CHECK-LABEL: @_Z5test6v()
 210 // CHECK:   invoke void @_Z9may_throwv()
 211 // CHECK-NEXT:           to label %{{.*}} unwind label %[[EHCLEANUP_BB0:.*]]
 212
 213 // CHECK: [[EHCLEANUP_BB0]]:
 214 // CHECK-NEXT:   %[[CLEANUPPAD0:.*]] = cleanuppad within none []
 215 // CHECK-NEXT:   call noundef ptr @_ZN7CleanupD1Ev(ptr {{.*}}) {{.*}} [ "funclet"(token %[[CLEANUPPAD0]]) ]
 216 // CHECK-NEXT:   cleanupret from %[[CLEANUPPAD0]] unwind label %[[CATCH_DISPATCH_BB:.*]]
 217
 218 // CHECK: [[CATCH_DISPATCH_BB]]:
 219 // CHECK-NEXT:  %[[CATCHSWITCH:.*]] = catchswitch within none [label %[[CATCHSTART_BB:.*]]] unwind label %[[EHCLEANUP_BB1:.*]]
 220
 221 // CHECK: [[CATCHSTART_BB]]:
 222 // CHECK-NEXT:   %[[CATCHPAD:.*]] = catchpad within %[[CATCHSWITCH]] [ptr @_ZTIi]
 223 // CHECK:   br i1 %{{.*}}, label %[[CATCH_INT_BB:.*]], label %[[RETHROW_BB:.*]]
 224
 225 // CHECK: [[CATCH_INT_BB]]:
 226 // CHECK:   invoke void @_Z9may_throwv() [ "funclet"(token %[[CATCHPAD]]) ]
 227 // CHECK-NEXT:           to label %[[INVOKE_CONT_BB:.*]] unwind label %[[EHCLEANUP_BB2:.*]]
 228
 229 // CHECK: [[INVOKE_CONT_BB]]:
 230 // CHECK:   catchret from %[[CATCHPAD]] to label %{{.*}}
 231
 232 // CHECK: [[RETHROW_BB]]:
 233 // CHECK-NEXT:   invoke void @llvm.wasm.rethrow() {{.*}} [ "funclet"(token %[[CATCHPAD]]) ]
 234 // CHECK-NEXT:          to label %[[UNREACHABLE_BB:.*]] unwind label %[[EHCLEANUP_BB1:.*]]
 235
 236 // CHECK: [[EHCLEANUP_BB2]]:
 237 // CHECK-NEXT:   %[[CLEANUPPAD2:.*]] = cleanuppad within %[[CATCHPAD]] []
 238 // CHECK-NEXT:   call noundef ptr @_ZN7CleanupD1Ev(ptr {{[^,]*}} %{{.*}}) {{.*}} [ "funclet"(token %[[CLEANUPPAD2]]) ]
 239 // CHECK-NEXT:   cleanupret from %[[CLEANUPPAD2]] unwind label %[[EHCLEANUP_BB3:.*]]
 240
 241 // CHECK: [[EHCLEANUP_BB3]]:
 242 // CHECK-NEXT:   %[[CLEANUPPAD3:.*]] = cleanuppad within %[[CATCHPAD]] []
 243 // CHECK:   cleanupret from %[[CLEANUPPAD3]] unwind label %[[EHCLEANUP_BB1:.*]]
 244
 245 // CHECK: [[EHCLEANUP_BB1]]:
 246 // CHECK-NEXT:   %[[CLEANUPPAD1:.*]] = cleanuppad within none []
 247 // CHECK-NEXT:   call noundef ptr @_ZN7CleanupD1Ev(ptr {{[^,]*}} %{{.*}}) {{.*}} [ "funclet"(token %[[CLEANUPPAD1]]) ]
 248 // CHECK-NEXT:   cleanupret from %[[CLEANUPPAD1]] unwind to caller
 249
 250 // CHECK: [[UNREACHABLE_BB]]:
 251 // CHECK-NEXT:   unreachable
 252
 253 // Nested try-catches within a try with cleanups
 254 void test7() {
 255   Cleanup c1;
 256   may_throw();
 257   try {
 258     Cleanup c2;
 259     may_throw();
 260     try {
 261       Cleanup c3;
 262       may_throw();
 263     } catch (int) {
 264       may_throw();
 265     } catch (double) {
 266       may_throw();
 267     }
 268   } catch (int) {
 269     may_throw();
 270   } catch (...) {
 271     may_throw();
 272   }
 273 }
 274
 275 // CHECK-LABEL: @_Z5test7v()
 276 // CHECK:   invoke void @_Z9may_throwv()
 277
 278 // CHECK:   invoke void @_Z9may_throwv()
 279
 280 // CHECK:   invoke void @_Z9may_throwv()
 281
 282 // CHECK:   %[[CLEANUPPAD0:.*]] = cleanuppad within none []
 283 // CHECK:   cleanupret from %[[CLEANUPPAD0]] unwind label
 284
 285 // CHECK:   %[[CATCHSWITCH0:.*]] = catchswitch within none
 286
 287 // CHECK:   %[[CATCHPAD0:.*]] = catchpad within %[[CATCHSWITCH0]] [ptr @_ZTIi, ptr @_ZTId]
 288
 289 // CHECK:   invoke void @_Z9may_throwv() [ "funclet"(token %[[CATCHPAD0]]) ]
 290
 291 // CHECK:   catchret from %[[CATCHPAD0]] to label
 292
 293 // CHECK:   invoke void @_Z9may_throwv() [ "funclet"(token %[[CATCHPAD0]]) ]
 294
 295 // CHECK:   catchret from %[[CATCHPAD0]] to label
 296
 297 // CHECK:   invoke void @llvm.wasm.rethrow() {{.*}} [ "funclet"(token %[[CATCHPAD0]]) ]
 298
 299 // CHECK:   %[[CLEANUPPAD1:.*]] = cleanuppad within %[[CATCHPAD0]] []
 300 // CHECK:   cleanupret from %[[CLEANUPPAD1]] unwind label
 301
 302 // CHECK:   %[[CLEANUPPAD2:.*]] = cleanuppad within %[[CATCHPAD0]] []
 303 // CHECK:   cleanupret from %[[CLEANUPPAD2]] unwind label
 304
 305 // CHECK:   %[[CLEANUPPAD3:.*]] = cleanuppad within none []
 306 // CHECK:   cleanupret from %[[CLEANUPPAD3]] unwind label
 307
 308 // CHECK:   %[[CATCHSWITCH1:.*]] = catchswitch within none
 309
 310 // CHECK:   %[[CATCHPAD1:.*]] = catchpad within %[[CATCHSWITCH1]] [ptr @_ZTIi, ptr null]
 311
 312 // CHECK:   invoke void @_Z9may_throwv() [ "funclet"(token %[[CATCHPAD1]]) ]
 313
 314 // CHECK:   catchret from %[[CATCHPAD1]] to label
 315
 316 // CHECK:   invoke void @_Z9may_throwv() [ "funclet"(token %[[CATCHPAD1]]) ]
 317
 318 // CHECK:   invoke void @__cxa_end_catch() [ "funclet"(token %[[CATCHPAD1]]) ]
 319
 320 // CHECK:   catchret from %[[CATCHPAD1]] to label
 321
 322 // CHECK:   %[[CLEANUPPAD4:.*]] = cleanuppad within %[[CATCHPAD1]] []
 323 // CHECK:   invoke void @__cxa_end_catch() [ "funclet"(token %[[CLEANUPPAD4]]) ]
 324
 325 // CHECK:   cleanupret from %[[CLEANUPPAD4]] unwind label
 326
 327 // CHECK:   %[[CLEANUPPAD5:.*]] = cleanuppad within %[[CATCHPAD1]] []
 328 // CHECK:   cleanupret from %[[CLEANUPPAD5]] unwind label
 329
 330 // CHECK:   %[[CLEANUPPAD6:.*]] = cleanuppad within none []
 331 // CHECK:   cleanupret from %[[CLEANUPPAD6]] unwind to caller
 332
 333 // CHECK:   unreachable
 334
 335 // CHECK:   %[[CLEANUPPAD7:.*]] = cleanuppad within %[[CLEANUPPAD4]] []
 336 // CHECK:   call void @_ZSt9terminatev() {{.*}} [ "funclet"(token %[[CLEANUPPAD7]]) ]
 337 // CHECK:   unreachable
 338
 339 // Nested try-catches within a catch
 340 void test8() {
 341   try {
 342     may_throw();
 343   } catch (int) {
 344     try {
 345       may_throw();
 346     } catch (int) {
 347       may_throw();
 348     }
 349   }
 350 }
 351
 352 // CHECK-LABEL: @_Z5test8v()
 353 // CHECK:   invoke void @_Z9may_throwv()
 354
 355 // CHECK:   %[[CATCHSWITCH0:.*]] = catchswitch within none
 356
 357 // CHECK:   %[[CATCHPAD0:.*]] = catchpad within %[[CATCHSWITCH0]] [ptr @_ZTIi]
 358
 359 // CHECK:   invoke void @_Z9may_throwv() [ "funclet"(token %[[CATCHPAD0]]) ]
 360
 361 // CHECK:   %[[CATCHSWITCH1:.*]] = catchswitch within %[[CATCHPAD0]]
 362
 363 // CHECK:   %[[CATCHPAD1:.*]] = catchpad within %[[CATCHSWITCH1]] [ptr @_ZTIi]
 364
 365 // CHECK:   invoke void @_Z9may_throwv() [ "funclet"(token %[[CATCHPAD1]]) ]
 366
 367 // CHECK:   catchret from %[[CATCHPAD1]] to label
 368
 369 // CHECK:   invoke void @llvm.wasm.rethrow() {{.*}} [ "funclet"(token %[[CATCHPAD1]]) ]
 370
 371 // CHECK:   catchret from %[[CATCHPAD0]] to label
 372
 373 // CHECK:   call void @llvm.wasm.rethrow() {{.*}} [ "funclet"(token %[[CATCHPAD0]]) ]
 374 // CHECK:   unreachable
 375
 376 // CHECK:   %[[CLEANUPPAD0:.*]] = cleanuppad within %[[CATCHPAD1]] []
 377 // CHECK:   cleanupret from %[[CLEANUPPAD0]] unwind label
 378
 379 // CHECK:   %[[CLEANUPPAD1:.*]] = cleanuppad within %[[CATCHPAD0]] []
 380 // CHECK:   cleanupret from %[[CLEANUPPAD1]] unwind to caller
 381
 382 // CHECK:   unreachable
 383
 384 // RUN: %clang_cc1 %s -triple wasm32-unknown-unknown -fms-extensions -fexceptions -fcxx-exceptions -exception-model=wasm -target-feature +exception-handling -emit-llvm -o - -std=c++11 2>&1 | FileCheck %s --check-prefix=WARNING-DEFAULT
 385 // RUN: %clang_cc1 %s -triple wasm32-unknown-unknown -fms-extensions -fexceptions -fcxx-exceptions -exception-model=wasm -target-feature +exception-handling -Wwasm-exception-spec -emit-llvm -o - -std=c++11 2>&1 | FileCheck %s --check-prefix=WARNING-ON
 386 // RUN: %clang_cc1 %s -triple wasm32-unknown-unknown -fms-extensions -fexceptions -fcxx-exceptions -exception-model=wasm -target-feature +exception-handling -Wno-wasm-exception-spec -emit-llvm -o - -std=c++11 2>&1 | FileCheck %s --check-prefix=WARNING-OFF
 387 // RUN: %clang_cc1 %s -triple wasm32-unknown-unknown -fexceptions -fcxx-exceptions -emit-llvm -o - -std=c++11 2>&1 | FileCheck %s --check-prefix=EM-EH-WARNING
 388
 389 // Wasm EH ignores dynamic exception specifications with types at the moment.
 390 // This is controlled by -Wwasm-exception-spec, which is on by default. This
 391 // warning can be suppressed with -Wno-wasm-exception-spec. Checks if a warning
 392 // message is correctly printed or not printed depending on the options.
 393 void test9() throw(int) {
 394 }
 395 // WARNING-DEFAULT: warning: dynamic exception specifications with types are currently ignored in wasm
 396 // WARNING-ON: warning: dynamic exception specifications with types are currently ignored in wasm
 397 // WARNING-OFF-NOT: warning: dynamic exception specifications with types are currently ignored in wasm
 398 // EM-EH-WARNING: warning: dynamic exception specifications with types are currently ignored in wasm
 399
 400 // Wasm curremtly treats 'throw()' in the same way as 'noexept'. Check if the
 401 // same warning message is printed as if when a 'noexcept' function throws.
 402 void test10() throw() {
 403   throw 3;
 404 }
 405 // WARNING-DEFAULT: warning: 'test10' has a non-throwing exception specification but can still throw
 406 // WARNING-DEFAULT: function declared non-throwing here
 407
 408 // Here we only check if the command enables wasm exception handling in the
 409 // backend so that exception handling instructions can be generated in .s file.
 410
 411 // RUN: %clang_cc1 %s -triple wasm32-unknown-unknown -fms-extensions -fexceptions -fcxx-exceptions -mllvm -wasm-enable-eh -exception-model=wasm -target-feature +exception-handling -S -o - -std=c++11 | FileCheck %s --check-prefix=ASSEMBLY
 412
 413 // ASSEMBLY: try
 414 // ASSEMBLY: catch
 415 // ASSEMBLY: rethrow
 416 // ASSEMBLY: end_try