SR-3175: Include the terminating signal number in the driver output

* Add the signal number of the terminated task to the output of the driver on platforms for which the signal number is available. The new key in the parseable driver output is "signal".
* Add a test to verify that the signal number is emitted.
* Add documentation for the new "signal" key emitted in the parseable driver output.

https://bugs.swift.org/browse/SR-3175

Author: matthewcarroll

docs/DriverParseableOutput.rst

@@ -104,15 +104,17 @@ As with all task-based message, it will include the task's PID under the "pid"
 key. It may include an error message describing the signal under the
 "error-message" key. As with the "finished" message, it may include the
 stdout/stderr of the task under the "output" key; if this key is missing, no
-output was generated by the task.
+output was generated by the task. It may include the "signal" key,
+the terminating signal number. (This may not be available on all platforms.)
 
 Example::
 
    {
      "kind": "signalled",
      "name": "compile",
      "pid": 12345,
-     "error-message": "Segmentation fault: 11"
+     "error-message": "Segmentation fault: 11",
+     "signal": 4
      // "output" key omitted because there was no stdout/stderr.
    }
 

include/swift/AST/DiagnosticsDriver.def

@@ -44,8 +44,10 @@ WARNING(warning_parallel_execution_not_supported,none,
 
 ERROR(error_unable_to_execute_command,none,
       "unable to execute command: %0", (StringRef))
-ERROR(error_command_signalled,none,
+ERROR(error_command_signalled_without_signal_number,none,
       "%0 command failed due to signal (use -v to see invocation)", (StringRef))
+ERROR(error_command_signalled,none,
+      "%0 command failed due to signal %1 (use -v to see invocation)", (StringRef, int))
 ERROR(error_command_failed,none,
       "%0 command failed with exit code %1 (use -v to see invocation)",
       (StringRef, int))

include/swift/Basic/TaskQueue.h

@@ -95,11 +95,15 @@ class TaskQueue {
   /// available and SeparateErrors was true.  (This may not be available on all
   /// platforms.)
   /// \param Context the context which was passed when the task was added
+  /// \param Signal the terminating signal number, if available.
+  /// This may not be available on all platforms. If it is ever provided,
+  /// it should not be removed in future versions of the compiler.
   ///
   /// \returns a TaskFinishedResponse indicating whether or not execution
   /// should proceed
   typedef std::function<TaskFinishedResponse(ProcessId Pid, StringRef ErrorMsg,
-                                             StringRef Output, StringRef Errors, void *Context)>
+                                             StringRef Output, StringRef Errors,
+                                             void *Context, Optional<int> Signal)>
     TaskSignalledCallback;
 #pragma clang diagnostic pop
 

include/swift/Driver/ParseableOutput.h

@@ -39,7 +39,7 @@ void emitFinishedMessage(raw_ostream &os, const Job &Cmd, ProcessId Pid,
 
 /// \brief Emits a "signalled" message to the given stream.
 void emitSignalledMessage(raw_ostream &os, const Job &Cmd, ProcessId Pid,
-                          StringRef ErrorMsg, StringRef Output);
+                          StringRef ErrorMsg, StringRef Output, Optional<int> Signal);
 
 /// \brief Emits a "skipped" message to the given stream.
 void emitSkippedMessage(raw_ostream &os, const Job &Cmd);

lib/Basic/Default/TaskQueue.inc

@@ -113,7 +113,7 @@ bool TaskQueue::execute(TaskBeganCallback Began, TaskFinishedCallback Finished,
       // a signal during execution.
       if (Signalled) {
         TaskFinishedResponse Response =
-            Signalled(PI.Pid, ErrMsg, StringRef(), StringRef(), T->Context);
+            Signalled(PI.Pid, ErrMsg, StringRef(), StringRef(), T->Context, None);
         ContinueExecution = Response != TaskFinishedResponse::StopExecution;
       } else {
         // If we don't have a Signalled callback, unconditionally stop.

lib/Basic/Unix/TaskQueue.inc

@@ -419,7 +419,7 @@ bool TaskQueue::execute(TaskBeganCallback Began, TaskFinishedCallback Finished,
             if (Signalled) {
               TaskFinishedResponse Response =
                   Signalled(T.getPid(), ErrorMsg, T.getOutput(), T.getErrors(),
-                            T.getContext());
+                            T.getContext(), Signal);
               if (Response == TaskFinishedResponse::StopExecution)
                 // If we have a TaskCrashedCallback, only set SubtaskFailed to
                 // true if the callback returns StopExecution.

lib/Driver/Compilation.cpp

@@ -615,7 +615,7 @@ int Compilation::performJobsImpl() {
 
   auto taskSignalled = [&](ProcessId Pid, StringRef ErrorMsg, StringRef Output,
                            StringRef Errors,
-                           void *Context) -> TaskFinishedResponse {
+                           void *Context, Optional<int> Signal) -> TaskFinishedResponse {
     const Job *SignalledCmd = (const Job *)Context;
 
     if (ShowDriverTimeCompilation) {
@@ -625,7 +625,7 @@ int Compilation::performJobsImpl() {
     if (Level == OutputLevel::Parseable) {
       // Parseable output was requested.
       parseable_output::emitSignalledMessage(llvm::errs(), *SignalledCmd, Pid,
-                                             ErrorMsg, Output);
+                                             ErrorMsg, Output, Signal);
     } else {
       // Otherwise, send the buffered output to stderr, though only if we
       // support getting buffered output.
@@ -636,9 +636,15 @@ int Compilation::performJobsImpl() {
     if (!ErrorMsg.empty())
       Diags.diagnose(SourceLoc(), diag::error_unable_to_execute_command,
                      ErrorMsg);
-
-    Diags.diagnose(SourceLoc(), diag::error_command_signalled,
-                   SignalledCmd->getSource().getClassName());
+    
+    if (Signal.hasValue()) {
+      Diags.diagnose(SourceLoc(), diag::error_command_signalled,
+                     SignalledCmd->getSource().getClassName(), Signal.getValue());
+    }
+    else {
+      Diags.diagnose(SourceLoc(), diag::error_command_signalled_without_signal_number,
+                     SignalledCmd->getSource().getClassName());
+    }
 
     // Since the task signalled, unconditionally set result to -2.
     Result = -2;

lib/Driver/ParseableOutput.cpp

@@ -201,15 +201,17 @@ class FinishedMessage : public TaskOutputMessage {
 
 class SignalledMessage : public TaskOutputMessage {
   std::string ErrorMsg;
+  Optional<int> Signal;
 public:
   SignalledMessage(const Job &Cmd, ProcessId Pid, StringRef Output,
-                   StringRef ErrorMsg) : TaskOutputMessage("signalled", Cmd,
+                   StringRef ErrorMsg, Optional<int> Signal) : TaskOutputMessage("signalled", Cmd,
                                                            Pid, Output),
-                                         ErrorMsg(ErrorMsg) {}
+                                         ErrorMsg(ErrorMsg), Signal(Signal) {}
 
   void provideMapping(swift::json::Output &out) override {
     TaskOutputMessage::provideMapping(out);
     out.mapOptional("error-message", ErrorMsg, std::string());
+    out.mapOptional("signal", Signal);
   }
 };
 
@@ -260,8 +262,8 @@ void parseable_output::emitFinishedMessage(raw_ostream &os,
 void parseable_output::emitSignalledMessage(raw_ostream &os,
                                             const Job &Cmd, ProcessId Pid,
                                             StringRef ErrorMsg,
-                                            StringRef Output) {
-  SignalledMessage msg(Cmd, Pid, Output, ErrorMsg);
+                                            StringRef Output, Optional<int> Signal) {
+  SignalledMessage msg(Cmd, Pid, Output, ErrorMsg, Signal);
   emitMessage(os, msg);
 }
 

test/Driver/crash.swift

@@ -2,7 +2,7 @@
 
 // RUN: not %swiftc_driver -emit-executable -o %t.exe %s -Xfrontend -debug-crash-after-parse 2>&1 | %FileCheck %s
 
-// CHECK: error: compile command failed due to signal
+// CHECK: error: compile command failed due to signal {{-?[0-9]+}}
 
 func anchor() {}
 anchor()