[SR-9001] Code completion assertion failure: (genericParams && "bindExtensionDecl didn't set generic params?"), function validateExtension, file swift/lib/Sema/TypeCheckDecl.cpp

[nathawes]

Previous ID	SR-9001
Radar	rdar://problem/45275782
Original Reporter	@nathawes
Type	Bug
Status	Resolved
Resolution	Done

Additional Detail from JIRA

Votes	0
Component/s	CodeCompletion
Labels	Bug, CompilerCrash
Assignee	None
Priority	Medium

md5: 9996cd05a38adb1cbadee48515149384

Issue Description:

To reproduce:

$ git clone https://github.com/bignerdranch/Deferred.git
$ cd Deferred
$ git checkout -f c374a6e7072ed88ed0c79299098ca2ba7c27e720
$ open Deferred.xcodeproj

Then in Xcode: # Select the October 3 swift.org dev snapshot toolchain

1. Navigate to Atomics.swift

2. On line 32, add a space after “func symbol” (before "<T>") and invoke code completion

Trace:

Thread 4 Crashed:
0   libsystem_kernel.dylib        0x00007fff7443bb86 __pthread_kill + 10
1   libsystem_pthread.dylib       0x00007fff744f1c50 pthread_kill + 285
2   libsystem_c.dylib             0x00007fff743a5268 __abort + 144
3   libsystem_c.dylib             0x00007fff743a51d8 abort + 142
4   libsystem_c.dylib             0x00007fff7436d868 __assert_rtn + 320
5   com.apple.SourceKitService.4.2.2018100301_osx0x0000000105dc4026 swift::TypeChecker::validateExtension(swift::ExtensionDecl*) + 1558
6   com.apple.SourceKitService.4.2.2018100301_osx0x0000000105e588d7 swift::typeCheckCompletionDecl(swift::Decl*) + 1191
7   com.apple.SourceKitService.4.2.2018100301_osx0x0000000105605aac (anonymous namespace)::CodeCompletionCallbacksImpl::doneParsing() + 2700
8   com.apple.SourceKitService.4.2.2018100301_osx0x0000000105f7309b swift::performDelayedParsing(swift::DeclContext*, swift::PersistentParserState&, swift::CodeCompletionCallbacksFactory*) + 395
9   com.apple.SourceKitService.4.2.2018100301_osx0x00000001055f5d09 swift::CompilerInstance::parseAndCheckTypesUpTo(swift::CompilerInstance::ImplicitImports const&, swift::SourceFile::ASTStage_t) + 841
10  com.apple.SourceKitService.4.2.2018100301_osx0x00000001055f5238 swift::CompilerInstance::performSemaUpTo(swift::SourceFile::ASTStage_t) + 616
11  com.apple.SourceKitService.4.2.2018100301_osx0x000000010546389f swiftCodeCompleteImpl(SourceKit::SwiftLangSupport&, llvm::MemoryBuffer*, unsigned int, (anonymous namespace)::SwiftCodeCompletionConsumer&, llvm::ArrayRef<char const*>, std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >&) + 2511
12  com.apple.SourceKitService.4.2.2018100301_osx0x0000000105462e63 SourceKit::SwiftLangSupport::codeComplete(llvm::MemoryBuffer*, unsigned int, SourceKit::CodeCompletionConsumer&, llvm::ArrayRef<char const*>) + 131
13  com.apple.SourceKitService.4.2.2018100301_osx0x00000001054bfc32 handleSemanticRequest(sourcekitd::RequestDict, std::__1::function<void (void*)>, sourcekitd_uid_s*, llvm::Optional<llvm::StringRef>, llvm::Optional<llvm::StringRef>, llvm::ArrayRef<char const*>) + 818
14  com.apple.SourceKitService.4.2.2018100301_osx0x00000001054bf87e void SourceKit::WorkQueue::DispatchData::callAndDelete<handleRequestImpl(void*, std::__1::function<void (void*)>)::$_4>(void*) + 142
15  libdispatch.dylib             0x00007fff742aedcb _dispatch_client_callout + 8
16  libdispatch.dylib             0x00007fff742b1b68 _dispatch_block_invoke_direct + 260
17  com.apple.SourceKitService.4.2.2018100301_osx0x0000000107f6751f executeBlock(void*) + 15
18  com.apple.SourceKitService.4.2.2018100301_osx0x00000001055825cd ExecuteOnThread_Dispatch(void*) + 13
19  libsystem_pthread.dylib       0x00007fff744ef33d _pthread_body + 126
20  libsystem_pthread.dylib       0x00007fff744f22a7 _pthread_start + 70
21  libsystem_pthread.dylib       0x00007fff744ee425 thread_start + 13 

[nathawes]

@swift-ci create

[rintaro]

$ cat test.swift
#if false
extension Optional {
#^COMPLETE^#
}
#endif
$ ../build/Ninja-ReleaseAssert/swift-macosx-x86_64/bin/swift-ide-test -code-completion -code-completion-token=COMPLETE -source-filename test.swift 
found code completion token COMPLETE at offset 33
found code completion token COMPLETE at offset 33
Assertion failed: (genericParams && "bindExtensionDecl didn't set generic params?"), function validateExtension, file /Users/rintaro/Repositories/swift-oss/swift/lib/Sema/TypeCheckDecl.cpp, line 4978.
Stack dump:
0.  Program arguments: ../build/Ninja-ReleaseAssert/swift-macosx-x86_64/bin/swift-ide-test -code-completion -code-completion-token=COMPLETE -source-filename test.swift 
0  swift-ide-test           0x00000001098a8268 llvm::sys::PrintStackTrace(llvm::raw_ostream&) + 40
1  swift-ide-test           0x00000001098a7238 llvm::sys::RunSignalHandlers() + 248
2  swift-ide-test           0x00000001098a8882 SignalHandler(int) + 258
3  libsystem_platform.dylib 0x00007fff6e3ceb3d _sigtramp + 29
4  libsystem_platform.dylib 0x0000000000003e58 _sigtramp + 2445497144
5  libsystem_c.dylib        0x00007fff6e28d1c9 abort + 127
6  libsystem_c.dylib        0x00007fff6e255868 basename_r + 0
7  swift-ide-test           0x0000000106440b76 swift::TypeChecker::validateExtension(swift::ExtensionDecl*) + 1558
8  swift-ide-test           0x00000001064d30f4 swift::typeCheckCompletionDecl(swift::Decl*) + 100
9  swift-ide-test           0x0000000105c6e30b (anonymous namespace)::CodeCompletionCallbacksImpl::doneParsing() + 2715
10 swift-ide-test           0x0000000106668cab swift::performDelayedParsing(swift::DeclContext*, swift::PersistentParserState&, swift::CodeCompletionCallbacksFactory*) + 395
11 swift-ide-test           0x0000000105c5b139 swift::CompilerInstance::parseAndCheckTypesUpTo(swift::CompilerInstance::ImplicitImports const&, swift::SourceFile::ASTStage_t) + 841
12 swift-ide-test           0x0000000105c5a668 swift::CompilerInstance::performSemaUpTo(swift::SourceFile::ASTStage_t) + 616
13 swift-ide-test           0x0000000105bdd4bb main + 24795
14 libdyld.dylib            0x00007fff6e1e50a5 start + 1
Abort trap: 6

[slavapestov]

Rintaro fixed this: #20015