[clang] [LifetimeSafety] Handle escape through assignment to global storage (PR #181646)

[Gábor Horváth via cfe-commits]

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@@ -113,12 +113,31 @@ View escape_through_unannotated_call(const MyObj& in [[clang::noescape]]) { // e
   return no_annotation_identity(in); // expected-note {{returned here}}
 }
 
-View global_view;
+View global_view; // expected-note {{escapes to this global storage}}
 
-// FIXME: Escaping through a global variable is not detected.
-void escape_through_global_var(const MyObj& in [[clang::noescape]]) {
+void escape_through_global_var(const MyObj& in [[clang::noescape]]) { // expected-warning {{parameter is marked [[clang::noescape]] but escapes}}
   global_view = in;
 }
+struct ObjWithStaticField {
+  static int *static_field; // expected-note {{escapes to this global storage}}
+}; 
+  
+void escape_to_static_data_member(int *data [[clang::noescape]]) { // expected-warning {{parameter is marked [[clang::noescape]] but escapes}}
+  ObjWithStaticField::static_field = data;
+}
+
+
+
+void escape_through_static_local(int *data [[clang::noescape]]) { // expected-warning {{parameter is marked [[clang::noescape]] but escapes}}
+  static int *static_local; // expected-note {{escapes to this global storage}}
+  static_local = data;
+}
+
+thread_local int *thread_local_storage; // expected-note {{escapes to this global storage}}
+
+void escape_through_thread_local(int *data [[clang::noescape]]) { // expected-warning {{parameter is marked [[clang::noescape]] but escapes}}
+  thread_local_storage = data;
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Xazax-hun wrote:

Sorry, I just realized how easy to misunderstand my point here. What I meant was, I wonder if for `noescape` arguments we might want to warn as soon as the assignment to the global happens? That being said, I think it might be fine not to do that if we cover the `save_globals` style scenario later on down the line.  

https://github.com/llvm/llvm-project/pull/181646