Don't try to create Expressions when the process is running.

lldb/source/Expression/FunctionCaller.cpp

@@ -65,17 +65,31 @@ bool FunctionCaller::WriteFunctionWrapper(
     ExecutionContext &exe_ctx, DiagnosticManager &diagnostic_manager) {
   Process *process = exe_ctx.GetProcessPtr();
 
-  if (!process)
+  if (!process) {
+    diagnostic_manager.Printf(eDiagnosticSeverityError, "no process.");
     return false;
-
+  }
+
   lldb::ProcessSP jit_process_sp(m_jit_process_wp.lock());
 
-  if (process != jit_process_sp.get())
+  if (process != jit_process_sp.get()) {
+    diagnostic_manager.Printf(eDiagnosticSeverityError,
+                             "process does not match the stored process.");
     return false;
-
-  if (!m_compiled)
+  }
+
+  if (process->GetState() != lldb::eStateStopped) {
+    diagnostic_manager.Printf(eDiagnosticSeverityError, 
+                              "process is not stopped");
     return false;
+  }
 
+  if (!m_compiled) {
+    diagnostic_manager.Printf(eDiagnosticSeverityError, 
+                              "function not compiled");
+    return false;
+  }
+
   if (m_JITted)
     return true;
 
@@ -212,6 +226,17 @@ bool FunctionCaller::WriteFunctionArguments(
 bool FunctionCaller::InsertFunction(ExecutionContext &exe_ctx,
                                     lldb::addr_t &args_addr_ref,
                                     DiagnosticManager &diagnostic_manager) {
+  // Since we might need to call allocate memory and maybe call code to make
+  // the caller, we need to be stopped.
+  Process *process = exe_ctx.GetProcessPtr();
+  if (!process) {
+    diagnostic_manager.PutString(eDiagnosticSeverityError, "no process");
+    return false;
+  }
+  if (process->GetState() != lldb::eStateStopped) {
+    diagnostic_manager.PutString(eDiagnosticSeverityError, "process running");
+    return false;
+  }
   if (CompileFunction(exe_ctx.GetThreadSP(), diagnostic_manager) != 0)
     return false;
   if (!WriteFunctionWrapper(exe_ctx, diagnostic_manager))

lldb/source/Expression/UserExpression.cpp

@@ -176,16 +176,22 @@ UserExpression::Evaluate(ExecutionContext &exe_ctx,
 
   Process *process = exe_ctx.GetProcessPtr();
 
-  if (process == nullptr || process->GetState() != lldb::eStateStopped) {
-    if (execution_policy == eExecutionPolicyAlways) {
-      LLDB_LOG(log, "== [UserExpression::Evaluate] Expression may not run, but "
-                    "is not constant ==");
+  if (process == nullptr && execution_policy == eExecutionPolicyAlways) {
+    LLDB_LOG(log, "== [UserExpression::Evaluate] No process, but the policy is "
+                  "eExecutionPolicyAlways");
 
-      error.SetErrorString("expression needed to run but couldn't");
+    error.SetErrorString("expression needed to run but couldn't: no process");
 
-      return execution_results;
-    }
+    return execution_results;
   }
+  // Since we might need to call allocate memory and maybe call code to make
+  // the caller, we need to be stopped.
+  if (process != nullptr && process->GetState() != lldb::eStateStopped) {
+    error.SetErrorString("Can't make a function caller while the process is " 
+                          "running");
+    return execution_results;
+  }
+
 
   // Explicitly force the IR interpreter to evaluate the expression when the
   // there is no process that supports running the expression for us. Don't

lldb/source/Expression/UtilityFunction.cpp

@@ -64,6 +64,13 @@ FunctionCaller *UtilityFunction::MakeFunctionCaller(
     error.SetErrorString("Can't make a function caller without a process.");
     return nullptr;
   }
+  // Since we might need to call allocate memory and maybe call code to make
+  // the caller, we need to be stopped.
+  if (process_sp->GetState() != lldb::eStateStopped) {
+    error.SetErrorString("Can't make a function caller while the process is " 
+                         "running");
+    return nullptr;
+  }
 
   Address impl_code_address;
   impl_code_address.SetOffset(StartAddress());

lldb/source/Plugins/ExpressionParser/Clang/ClangUtilityFunction.cpp

@@ -99,6 +99,12 @@ bool ClangUtilityFunction::Install(DiagnosticManager &diagnostic_manager,
     return false;
   }
 
+  // Since we might need to call allocate memory and maybe call code to make
+  // the caller, we need to be stopped.
+  if (process->GetState() != lldb::eStateStopped) {
+    diagnostic_manager.PutString(eDiagnosticSeverityError, "process running");
+    return false;
+  }
   //////////////////////////
   // Parse the expression
   //

lldb/source/Target/Process.cpp

@@ -1431,7 +1431,10 @@ uint32_t Process::AssignIndexIDToThread(uint64_t thread_id) {
 }
 
 StateType Process::GetState() {
-  return m_public_state.GetValue();
+  if (CurrentThreadIsPrivateStateThread())
+    return m_private_state.GetValue();
+  else
+    return m_public_state.GetValue();
 }
 
 void Process::SetPublicState(StateType new_state, bool restarted) {