Sema: Fix crash with unbound generic types in patterns

Author: slavapestov

lib/Sema/TypeCheckPattern.cpp

@@ -869,6 +869,12 @@ bool TypeChecker::typeCheckPattern(Pattern *P, DeclContext *dc,
   case PatternKind::Typed: {
     TypedPattern *TP = cast<TypedPattern>(P);
     bool hadError = validateTypedPattern(*this, dc, TP, options, &resolver);
+
+    // If we have unbound generic types, don't apply them below; instead,
+    // the caller will call typeCheckBinding() later.
+    if (P->getType()->hasUnboundGenericType())
+      return hadError;
+
     Pattern *subPattern = TP->getSubPattern();
     if (coercePatternToType(subPattern, dc, P->getType(),
                             options|TR_FromNonInferredPattern, &resolver,

validation-test/compiler_crashers/28762-valuetype-hasunboundgenerictype-valuetype-hastypeparameter.swift renamed to validation-test/compiler_crashers_fixed/28762-valuetype-hasunboundgenerictype-valuetype-hastypeparameter.swift

@@ -6,5 +6,5 @@
 // See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 // REQUIRES: asserts
-// RUN: not --crash %target-swift-frontend %s -emit-ir
+// RUN: not %target-swift-frontend %s -emit-ir
 guard let f==A:UnfoldSequence