[swiftc (57 vs. 5396)] Add crasher in swift::TypeBase::getCanonicalType(...)

Add test case for crash triggered in `swift::TypeBase::getCanonicalType(...)`.

Current number of unresolved compiler crashers: 57 (5396 resolved)

/cc @lattner - just wanted to let you know that this crasher caused an assertion failure for the assertion `Result && "Case not implemented!"` added on 2011-03-22 by you in commit fd2bf74 :-)

Assertion failure in [`lib/AST/Type.cpp (line 1292)`](https://github.com/apple/swift/blob/master/lib/AST/Type.cpp#L1292):

```
Assertion `Result && "Case not implemented!"' failed.

When executing: swift::CanType swift::TypeBase::getCanonicalType()
```

Assertion context:

```
  }
  }

  // Cache the canonical type for future queries.
  assert(Result && "Case not implemented!");
  CanonicalType = Result;
  return CanType(Result);
}

```
Stack trace:

```
0 0x000000000351a038 llvm::sys::PrintStackTrace(llvm::raw_ostream&) (/path/to/swift/bin/swift+0x351a038)
1 0x000000000351a776 SignalHandler(int) (/path/to/swift/bin/swift+0x351a776)
2 0x00007f867b1ae3e0 __restore_rt (/lib/x86_64-linux-gnu/libpthread.so.0+0x113e0)
3 0x00007f8679b14428 gsignal /build/glibc-Qz8a69/glibc-2.23/signal/../sysdeps/unix/sysv/linux/raise.c:54:0
4 0x00007f8679b1602a abort /build/glibc-Qz8a69/glibc-2.23/stdlib/abort.c:91:0
5 0x00007f8679b0cbd7 __assert_fail_base /build/glibc-Qz8a69/glibc-2.23/assert/assert.c:92:0
6 0x00007f8679b0cc82 (/lib/x86_64-linux-gnu/libc.so.6+0x2dc82)
7 0x0000000000e8b248 swift::TypeBase::getCanonicalType() (/path/to/swift/bin/swift+0xe8b248)
8 0x0000000000ce99d0 (anonymous namespace)::FindCapturedVars::checkType(swift::Type, swift::SourceLoc) (/path/to/swift/bin/swift+0xce99d0)
9 0x0000000000ce9e3a (anonymous namespace)::FindCapturedVars::walkToExprPre(swift::Expr*) (/path/to/swift/bin/swift+0xce9e3a)
10 0x0000000000e1332f swift::ASTVisitor<(anonymous namespace)::Traversal, swift::Expr*, swift::Stmt*, bool, swift::Pattern*, bool, void>::visit(swift::Expr*) (/path/to/swift/bin/swift+0xe1332f)
11 0x0000000000e11942 swift::ASTVisitor<(anonymous namespace)::Traversal, swift::Expr*, swift::Stmt*, bool, swift::Pattern*, bool, void>::visit(swift::Expr*) (/path/to/swift/bin/swift+0xe11942)
12 0x0000000000e1395e (anonymous namespace)::Traversal::visitApplyExpr(swift::ApplyExpr*) (/path/to/swift/bin/swift+0xe1395e)
13 0x0000000000e14165 swift::ASTVisitor<(anonymous namespace)::Traversal, swift::Expr*, swift::Stmt*, bool, swift::Pattern*, bool, void>::visit(swift::Stmt*) (/path/to/swift/bin/swift+0xe14165)
14 0x0000000000e13d40 swift::ASTVisitor<(anonymous namespace)::Traversal, swift::Expr*, swift::Stmt*, bool, swift::Pattern*, bool, void>::visit(swift::Stmt*) (/path/to/swift/bin/swift+0xe13d40)
15 0x0000000000e106ee swift::Stmt::walk(swift::ASTWalker&) (/path/to/swift/bin/swift+0xe106ee)
16 0x0000000000ce8bb0 swift::TypeChecker::computeCaptures(swift::AnyFunctionRef) (/path/to/swift/bin/swift+0xce8bb0)
17 0x0000000000ceb567 (anonymous namespace)::FindCapturedVars::propagateCaptures(swift::AnyFunctionRef, swift::SourceLoc) (/path/to/swift/bin/swift+0xceb567)
18 0x0000000000cea23a (anonymous namespace)::FindCapturedVars::walkToExprPre(swift::Expr*) (/path/to/swift/bin/swift+0xcea23a)
19 0x0000000000e14139 swift::ASTVisitor<(anonymous namespace)::Traversal, swift::Expr*, swift::Stmt*, bool, swift::Pattern*, bool, void>::visit(swift::Stmt*) (/path/to/swift/bin/swift+0xe14139)
20 0x0000000000e13d40 swift::ASTVisitor<(anonymous namespace)::Traversal, swift::Expr*, swift::Stmt*, bool, swift::Pattern*, bool, void>::visit(swift::Stmt*) (/path/to/swift/bin/swift+0xe13d40)
21 0x0000000000e106ee swift::Stmt::walk(swift::ASTWalker&) (/path/to/swift/bin/swift+0xe106ee)
22 0x0000000000ce8bb0 swift::TypeChecker::computeCaptures(swift::AnyFunctionRef) (/path/to/swift/bin/swift+0xce8bb0)
23 0x0000000000ceb567 (anonymous namespace)::FindCapturedVars::propagateCaptures(swift::AnyFunctionRef, swift::SourceLoc) (/path/to/swift/bin/swift+0xceb567)
24 0x0000000000cea23a (anonymous namespace)::FindCapturedVars::walkToExprPre(swift::Expr*) (/path/to/swift/bin/swift+0xcea23a)
25 0x0000000000e14139 swift::ASTVisitor<(anonymous namespace)::Traversal, swift::Expr*, swift::Stmt*, bool, swift::Pattern*, bool, void>::visit(swift::Stmt*) (/path/to/swift/bin/swift+0xe14139)
26 0x0000000000e13d40 swift::ASTVisitor<(anonymous namespace)::Traversal, swift::Expr*, swift::Stmt*, bool, swift::Pattern*, bool, void>::visit(swift::Stmt*) (/path/to/swift/bin/swift+0xe13d40)
27 0x0000000000e106ee swift::Stmt::walk(swift::ASTWalker&) (/path/to/swift/bin/swift+0xe106ee)
28 0x0000000000ce8bb0 swift::TypeChecker::computeCaptures(swift::AnyFunctionRef) (/path/to/swift/bin/swift+0xce8bb0)
29 0x0000000000ceb567 (anonymous namespace)::FindCapturedVars::propagateCaptures(swift::AnyFunctionRef, swift::SourceLoc) (/path/to/swift/bin/swift+0xceb567)
30 0x0000000000cea23a (anonymous namespace)::FindCapturedVars::walkToExprPre(swift::Expr*) (/path/to/swift/bin/swift+0xcea23a)
31 0x0000000000e1368c (anonymous namespace)::Traversal::visitCollectionExpr(swift::CollectionExpr*) (/path/to/swift/bin/swift+0xe1368c)
32 0x0000000000e11942 swift::ASTVisitor<(anonymous namespace)::Traversal, swift::Expr*, swift::Stmt*, bool, swift::Pattern*, bool, void>::visit(swift::Expr*) (/path/to/swift/bin/swift+0xe11942)
33 0x0000000000e1395e (anonymous namespace)::Traversal::visitApplyExpr(swift::ApplyExpr*) (/path/to/swift/bin/swift+0xe1395e)
34 0x0000000000e10f25 (anonymous namespace)::Traversal::doIt(swift::Decl*) (/path/to/swift/bin/swift+0xe10f25)
35 0x0000000000e13cd8 swift::ASTVisitor<(anonymous namespace)::Traversal, swift::Expr*, swift::Stmt*, bool, swift::Pattern*, bool, void>::visit(swift::Stmt*) (/path/to/swift/bin/swift+0xe13cd8)
36 0x0000000000e106ee swift::Stmt::walk(swift::ASTWalker&) (/path/to/swift/bin/swift+0xe106ee)
37 0x0000000000ce8bb0 swift::TypeChecker::computeCaptures(swift::AnyFunctionRef) (/path/to/swift/bin/swift+0xce8bb0)
38 0x0000000000c2232b typeCheckFunctionsAndExternalDecls(swift::TypeChecker&) (/path/to/swift/bin/swift+0xc2232b)
39 0x0000000000c22a39 swift::performTypeChecking(swift::SourceFile&, swift::TopLevelContext&, swift::OptionSet<swift::TypeCheckingFlags, unsigned int>, unsigned int, unsigned int) (/path/to/swift/bin/swift+0xc22a39)
40 0x0000000000999206 swift::CompilerInstance::performSema() (/path/to/swift/bin/swift+0x999206)
41 0x000000000047ca6a swift::performFrontend(llvm::ArrayRef<char const*>, char const*, void*, swift::FrontendObserver*) (/path/to/swift/bin/swift+0x47ca6a)
42 0x000000000043b2a7 main (/path/to/swift/bin/swift+0x43b2a7)
43 0x00007f8679aff830 __libc_start_main /build/glibc-Qz8a69/glibc-2.23/csu/../csu/libc-start.c:325:0
44 0x00000000004386e9 _start (/path/to/swift/bin/swift+0x4386e9)
```

Author: practicalswift

validation-test/compiler_crashers/28641-result-case-not-implemented.swift

@@ -0,0 +1,11 @@
+// This source file is part of the Swift.org open source project
+// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+
+// REQUIRES: deterministic-behavior
+// REQUIRES: asserts
+// RUN: not --crash %target-swift-frontend %s -emit-ir
+{let β=b&[{{{#keyPath(n&[{{{{{{{{{{{{{{{{{{{{{{{{{{a{{{{s