SILGen crash on try repeat/await repeat

[AnthonyLatsis]

Description

No response

Reproduction

func blackHole<T>(_: T) throws {}

func foo<each T>(_ t: repeat each T) throws {
  try repeat blackHole(each t)
}

Ditto await repeat.

Stack dump

Assertion failed: (init && init->canPerformPackExpansionInitialization() && "cannot emit a PackExpansionExpr without an appropriate context"), function visitPackExpansionExpr, file SILGenExpr.cpp, line 1646.
Please submit a bug report (https://swift.org/contributing/#reporting-bugs) and include the crash backtrace.
Stack dump:
0.	Program arguments: bin/swift-frontend -debug-diagnostic-names -diagnostic-style=llvm -emit-sil -enable-experimental-feature NoncopyableGenerics /Users/mac/Desktop/test.swift
1.	Swift version 6.0-dev (LLVM beb75c68bf9e0fb, Swift eb40cc56777bae4)
2.	Compiling with effective version 5.10
3.	While evaluating request ASTLoweringRequest(Lowering AST to SIL for module test)
4.	While silgen emitFunction SIL function "@$s4test3fooyyxxQpKRvzlF".
 for 'foo(_:)' (at /Users/mac/Desktop/test.swift:234:1)
Stack dump without symbol names (ensure you have llvm-symbolizer in your PATH or set the environment var `LLVM_SYMBOLIZER_PATH` to point to it):
0  swift-frontend           0x000000010a53e7e8 llvm::sys::PrintStackTrace(llvm::raw_ostream&, int) + 40
1  swift-frontend           0x000000010a53cc35 llvm::sys::RunSignalHandlers() + 85
2  swift-frontend           0x000000010a53ee3e SignalHandler(int) + 270
3  libsystem_platform.dylib 0x00007ff8058ea37d _sigtramp + 29
4  swift-frontend           0x000000010e06e9b8 swift::AnyRequestVTable const* swift::AnyRequestVTable::get<swift::LookupConformanceInModuleRequest>()::vtable + 72
5  libsystem_c.dylib        0x00007ff8057dba4d abort + 126
6  libsystem_c.dylib        0x00007ff8057dad60 err + 0
7  swift-frontend           0x0000000102bfb598 (anonymous namespace)::RValueEmitter::visitPackExpansionExpr(swift::PackExpansionExpr*, swift::Lowering::SGFContext) + 200
8  swift-frontend           0x0000000102be5cb6 swift::ASTVisitor<(anonymous namespace)::RValueEmitter, swift::Lowering::RValue, void, void, void, void, void, swift::Lowering::SGFContext>::visit(swift::Expr*, swift::Lowering::SGFContext) + 2470
9  swift-frontend           0x0000000102bf939e swift::Lowering::ASTVisitor<(anonymous namespace)::RValueEmitter, swift::Lowering::RValue, void, void, void, swift::Lowering::SGFContext>::visitTryExpr(swift::TryExpr*, swift::Lowering::SGFContext) + 94
10 swift-frontend           0x0000000102be59bf swift::ASTVisitor<(anonymous namespace)::RValueEmitter, swift::Lowering::RValue, void, void, void, void, void, swift::Lowering::SGFContext>::visit(swift::Expr*, swift::Lowering::SGFContext) + 1711
11 swift-frontend           0x0000000102bd5d11 swift::Lowering::SILGenFunction::emitRValue(swift::Expr*, swift::Lowering::SGFContext) + 209
12 swift-frontend           0x0000000102bdb874 swift::Lowering::SILGenFunction::emitIgnoredExpr(swift::Expr*) + 2020
13 swift-frontend           0x0000000102d2f90f (anonymous namespace)::StmtEmitter::visitBraceStmt(swift::BraceStmt*) + 2271
14 swift-frontend           0x0000000102d29491 swift::ASTVisitor<(anonymous namespace)::StmtEmitter, void, void, void, void, void, void>::visit(swift::Stmt*) + 81
15 swift-frontend           0x0000000102d2940a swift::Lowering::SILGenFunction::emitStmt(swift::Stmt*) + 42
16 swift-frontend           0x0000000102c3225c swift::Lowering::SILGenFunction::emitFunction(swift::FuncDecl*) + 956
17 swift-frontend           0x0000000102ab8530 swift::Lowering::SILGenModule::emitFunctionDefinition(swift::SILDeclRef, swift::SILFunction*) + 4512
18 swift-frontend           0x0000000102abbc15 swift::Lowering::SILGenModule::emitOrDelayFunction(swift::SILDeclRef) + 533
19 swift-frontend           0x0000000102ab7362 swift::Lowering::SILGenModule::emitFunction(swift::FuncDecl*) + 450
20 swift-frontend           0x0000000102ab718d swift::Lowering::SILGenModule::visitFuncDecl(swift::FuncDecl*) + 29
21 swift-frontend           0x0000000102ab6e54 swift::ASTVisitor<swift::Lowering::SILGenModule, void, void, void, void, void, void>::visit(swift::Decl*) + 996
22 swift-frontend           0x0000000102ab6a60 swift::Lowering::SILGenModule::visit(swift::Decl*) + 64
23 swift-frontend           0x0000000102ac0dc4 (anonymous namespace)::SILGenModuleRAII::emitSourceFile(swift::SourceFile*) + 340
24 swift-frontend           0x0000000102ac096f swift::ASTLoweringRequest::evaluate(swift::Evaluator&, swift::ASTLoweringDescriptor) const + 879
25 swift-frontend           0x0000000102d285de std::__1::unique_ptr<swift::SILModule, std::__1::default_delete<swift::SILModule>> swift::SimpleRequest<swift::ASTLoweringRequest, std::__1::unique_ptr<swift::SILModule, std::__1::default_delete<swift::SILModule>> (swift::ASTLoweringDescriptor), (swift::RequestFlags)9>::callDerived<0ul>(swift::Evaluator&, std::__1::integer_sequence<unsigned long, 0ul>) const + 142
26 swift-frontend           0x0000000102d284f8 swift::SimpleRequest<swift::ASTLoweringRequest, std::__1::unique_ptr<swift::SILModule, std::__1::default_delete<swift::SILModule>> (swift::ASTLoweringDescriptor), (swift::RequestFlags)9>::evaluateRequest(swift::ASTLoweringRequest const&, swift::Evaluator&) + 40
27 swift-frontend           0x0000000102adcb18 swift::ASTLoweringRequest::OutputType swift::Evaluator::getResultUncached<swift::ASTLoweringRequest, swift::ASTLoweringRequest::OutputType swift::evaluateOrFatal<swift::ASTLoweringRequest>(swift::Evaluator&, swift::ASTLoweringRequest)::'lambda'()>(swift::ASTLoweringRequest const&, swift::ASTLoweringRequest::OutputType swift::evaluateOrFatal<swift::ASTLoweringRequest>(swift::Evaluator&, swift::ASTLoweringRequest)::'lambda'()) + 264
28 swift-frontend           0x0000000102adc9f8 swift::ASTLoweringRequest::OutputType swift::Evaluator::operator()<swift::ASTLoweringRequest, swift::ASTLoweringRequest::OutputType swift::evaluateOrFatal<swift::ASTLoweringRequest>(swift::Evaluator&, swift::ASTLoweringRequest)::'lambda'(), (void*)0>(swift::ASTLoweringRequest const&, swift::ASTLoweringRequest::OutputType swift::evaluateOrFatal<swift::ASTLoweringRequest>(swift::Evaluator&, swift::ASTLoweringRequest)::'lambda'()) + 40
29 swift-frontend           0x0000000102ac1584 swift::ASTLoweringRequest::OutputType swift::evaluateOrFatal<swift::ASTLoweringRequest>(swift::Evaluator&, swift::ASTLoweringRequest) + 36
30 swift-frontend           0x0000000102ac14a0 swift::performASTLowering(swift::ModuleDecl*, swift::Lowering::TypeConverter&, swift::SILOptions const&, swift::IRGenOptions const*) + 256
31 swift-frontend           0x0000000101cf95bb swift::performCompileStepsPostSema(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 283
32 swift-frontend           0x0000000101d2ad83 performAction(swift::CompilerInstance&, int&, swift::FrontendObserver*)::$_29::operator()(swift::CompilerInstance&) const + 147
33 swift-frontend           0x0000000101d2acdd bool llvm::function_ref<bool (swift::CompilerInstance&)>::callback_fn<performAction(swift::CompilerInstance&, int&, swift::FrontendObserver*)::$_29>(long, swift::CompilerInstance&) + 29
34 swift-frontend           0x0000000101d2a0a1 llvm::function_ref<bool (swift::CompilerInstance&)>::operator()(swift::CompilerInstance&) const + 33
35 swift-frontend           0x0000000101d29038 withSemanticAnalysis(swift::CompilerInstance&, swift::FrontendObserver*, llvm::function_ref<bool (swift::CompilerInstance&)>, bool) + 392
36 swift-frontend           0x0000000101d21555 performAction(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 1349
37 swift-frontend           0x0000000101cfca66 performCompile(swift::CompilerInstance&, int&, swift::FrontendObserver*) + 262
38 swift-frontend           0x0000000101cfb44a swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) + 2794
39 swift-frontend           0x0000000101ba97ea run_driver(llvm::StringRef, llvm::ArrayRef<char const*>, llvm::ArrayRef<char const*>) + 2410
40 swift-frontend           0x0000000101ba8427 swift::mainEntry(int, char const**) + 1543
41 swift-frontend           0x0000000101ba7952 main + 34
42 dyld                     0x00007ff8055343a6 start + 1942
Abort trap: 6

Expected behavior

Handle as repeat try/repeat await or ban this keyword permutation if the former poses a substantial technical problem.

Environment

Swift version 6.0-dev (LLVM beb75c68bf9e0fb, Swift eb40cc5)
Target: x86_64-apple-macosx14.0

Additional information

No response