[CursorInfo] Fix a bug that caused solver-based cursor info to crash if invoked on a symbol from a different module

lib/IDE/CursorInfo.cpp

@@ -48,9 +48,14 @@ void typeCheckDeclAndParentClosures(ValueDecl *VD) {
     DC = DC->getParent();
   }
 
-  typeCheckASTNodeAtLoc(
-      TypeCheckASTNodeAtLocContext::declContext(VD->getDeclContext()),
-      VD->getLoc());
+  if (!VD->getInterfaceType()) {
+    // The decl has an interface time if it came from another module. In that
+    // case, there's nothing to do. Otherwise, type check the decl to get its
+    // type.
+    typeCheckASTNodeAtLoc(
+        TypeCheckASTNodeAtLocContext::declContext(VD->getDeclContext()),
+        VD->getLoc());
+  }
   if (auto VarD = dyn_cast<VarDecl>(VD)) {
     if (VarD->hasAttachedPropertyWrapper()) {
       // Type check any attached property wrappers so the annotated declaration

lib/IDE/SelectedOverloadInfo.cpp

@@ -36,6 +36,9 @@ swift::ide::getSelectedOverloadInfo(const Solution &S,
     if (Result.BaseTy) {
       Result.BaseTy = S.simplifyType(Result.BaseTy)->getRValueType();
     }
+    if (Result.BaseTy && Result.BaseTy->is<ModuleType>()) {
+      Result.BaseTy = nullptr;
+    }
 
     Result.Value = SelectedOverload->choice.getDeclOrNull();
     Result.ValueTy =

test/SourceKit/CursorInfo/cursor_in_stdlib_module.swift

@@ -0,0 +1,12 @@
+func test() {
+  // RUN: %sourcekitd-test -req=cursor -pos=%(line + 1):9 %s -- %s | %FileCheck %s
+  Swift.min(1, 2)
+}
+
+// CHECK: source.lang.swift.ref.function.free ()
+// CHECK-NEXT: min(_:_:)
+// CHECK-NEXT: s:s3minyxx_xtSLRzlF
+// CHECK-NEXT: source.lang.swift
+// CHECK-NEXT: <T where T : Comparable> (T, T) -> T
+// CHECK-NEXT: $syxx_xtcSLRzluD
+// CHECK-NEXT: Swift