[Incremental] stop if no -driver-continue-building-after-errors

Sources/SwiftDriver/Driver/CompilerMode.swift

@@ -80,6 +80,10 @@ extension CompilerMode {
     }
   }
 
+  public var isBatchCompile: Bool {
+    batchModeInfo != nil
+  }
+
   // Whether this compilation mode supports the use of bridging pre-compiled
   // headers.
   public var supportsBridgingPCH: Bool {

Sources/SwiftDriver/Driver/Driver.swift

@@ -859,12 +859,14 @@ extension Driver {
                            recordedInputModificationDates: recordedInputModificationDates)
       return
     }
-
-    try performTheBuild(allJobs: jobs, forceResponseFiles: forceResponseFiles)
-
-    buildRecordInfo?.writeBuildRecord(
-      jobs,
-      incrementalCompilationState?.skippedCompilationInputs)
+    do {
+      defer {
+        buildRecordInfo?.writeBuildRecord(
+          jobs,
+          incrementalCompilationState?.skippedCompilationInputs)
+      }
+      try performTheBuild(allJobs: jobs, forceResponseFiles: forceResponseFiles)
+    }
 
     // If requested, warn for options that weren't used by the driver after the build is finished.
     if parsedOptions.hasArgument(.driverWarnUnusedOptions) {
@@ -896,8 +898,11 @@ extension Driver {
     allJobs: [Job],
     forceResponseFiles: Bool
   ) throws {
+    let continueBuildingAfterErrors = computeContinueBuildingAfterErrors()
     try executor.execute(
-      workload: .init(allJobs, incrementalCompilationState),
+      workload: .init(allJobs,
+                      incrementalCompilationState,
+                      continueBuildingAfterErrors: continueBuildingAfterErrors),
       delegate: createToolExecutionDelegate(),
       numParallelJobs: numParallelJobs ?? 1,
       forceResponseFiles: forceResponseFiles,
@@ -1414,8 +1419,25 @@ extension Driver {
 
     return numJobs
   }
+
+  private mutating func computeContinueBuildingAfterErrors() -> Bool {
+    // Note: Batch mode handling of serialized diagnostics requires that all
+    // batches get to run, in order to make sure that all diagnostics emitted
+    // during the compilation end up in at least one serialized diagnostic file.
+    // Therefore, treat batch mode as implying -continue-building-after-errors.
+    // (This behavior could be limited to only when serialized diagnostics are
+    // being emitted, but this seems more consistent and less surprising for
+    // users.)
+    // FIXME: We don't really need (or want) a full ContinueBuildingAfterErrors.
+    // If we fail to precompile a bridging header, for example, there's no need
+    // to go on to compilation of source files, and if compilation of source files
+    // fails, we shouldn't try to link. Instead, we'd want to let all jobs finish
+    // but not schedule any new ones.
+    return compilerMode.isBatchCompile || parsedOptions.contains(.continueBuildingAfterErrors)
+  }
 }
 
+
 extension Diagnostic.Message {
   static func remark_max_determinism_overriding(_ option: Option) -> Diagnostic.Message {
     .remark("SWIFTC_MAXIMUM_DETERMINISM overriding \(option.spelling)")

Sources/SwiftDriver/Execution/DriverExecutor.swift

@@ -47,12 +47,26 @@ public protocol DriverExecutor {
   func description(of job: Job, forceResponseFiles: Bool) throws -> String
 }
 
-public enum DriverExecutorWorkload {
-  case all([Job])
-  case incremental(IncrementalCompilationState)
+public struct DriverExecutorWorkload {
+  public let continueBuildingAfterErrors: Bool
+  public enum Kind {
+    case all([Job])
+    case incremental(IncrementalCompilationState)
+  }
+  public let kind: Kind
+
+  public init(_ allJobs: [Job],
+       _ incrementalCompilationState: IncrementalCompilationState?,
+       continueBuildingAfterErrors: Bool
+  ) {
+      self.continueBuildingAfterErrors = continueBuildingAfterErrors
+      self.kind = incrementalCompilationState
+        .map {.incremental($0)}
+        ?? .all(allJobs)
+  }
 
-  init(_ allJobs: [Job], _ incrementalCompilationState: IncrementalCompilationState?) {
-    self = incrementalCompilationState.map {.incremental($0)} ?? .all(allJobs)
+  static public func all(_ jobs: [Job]) -> Self {
+    .init(jobs, nil, continueBuildingAfterErrors: false)
   }
 }
 

Sources/SwiftDriver/Jobs/Planning.swift

@@ -545,7 +545,7 @@ extension Driver {
   /// So, in order to avoid making jobs and rebatching, the code would have to just get outputs for each
   /// compilation. But `compileJob` intermixes the output computation with other stuff.
   mutating func formBatchedJobs(_ jobs: [Job], forIncremental: Bool) throws -> [Job] {
-    guard let _ = compilerMode.batchModeInfo else {
+    guard compilerMode.isBatchCompile else {
       // Don't even go through the logic so as to not print out confusing
       // "batched foobar" messages.
       return jobs

Sources/SwiftDriverExecution/MultiJobExecutor.swift

@@ -87,6 +87,12 @@ public final class MultiJobExecutor {
     /// any newly-required job. Set only once.
     private(set) var executeAllJobsTaskBuildEngine: LLTaskBuildEngine? = nil
 
+    /// If a job fails, the driver needs to stop running jobs.
+    private(set) var isBuildCancelled = false
+
+    /// The value of the option
+    let continueBuildingAfterErrors: Bool
+
 
     init(
       argsResolver: ArgsResolver,
@@ -106,7 +112,8 @@ public final class MultiJobExecutor {
         producerMap: self.producerMap,
         primaryIndices: self.primaryIndices,
         postCompileIndices: self.postCompileIndices,
-        incrementalCompilationState: self.incrementalCompilationState
+        incrementalCompilationState: self.incrementalCompilationState,
+        continueBuildingAfterErrors: self.continueBuildingAfterErrors
       ) = Self.fillInJobsAndProducers(workload)
 
       self.argsResolver = argsResolver
@@ -131,20 +138,21 @@ public final class MultiJobExecutor {
           producerMap: [VirtualPath: Int],
           primaryIndices: Range<Int>,
           postCompileIndices: Range<Int>,
-          incrementalCompilationState: IncrementalCompilationState?)
+          incrementalCompilationState: IncrementalCompilationState?,
+          continueBuildingAfterErrors: Bool)
     {
       var jobs = [Job]()
       var producerMap = [VirtualPath: Int]()
       let primaryIndices, postCompileIndices: Range<Int>
       let incrementalCompilationState: IncrementalCompilationState?
-      switch workload {
+      switch workload.kind {
       case let .incremental(ics):
         incrementalCompilationState = ics
         primaryIndices = Self.addJobs(
           ics.mandatoryPreOrCompileJobsInOrder,
           to: &jobs,
           producing: &producerMap
-          )
+        )
         postCompileIndices = Self.addJobs(
           ics.postCompileJobs,
           to: &jobs,
@@ -161,7 +169,8 @@ public final class MultiJobExecutor {
                producerMap: producerMap,
                primaryIndices: primaryIndices,
                postCompileIndices: postCompileIndices,
-               incrementalCompilationState: incrementalCompilationState)
+               incrementalCompilationState: incrementalCompilationState,
+               continueBuildingAfterErrors: workload.continueBuildingAfterErrors)
     }
 
     /// Allow for dynamically adding jobs, since some compile  jobs are added dynamically.
@@ -225,6 +234,19 @@ public final class MultiJobExecutor {
         executeAllJobsTaskBuildEngine!.taskNeedsInput(key, inputID: index)
       }
     }
+
+    fileprivate func cancelBuildIfNeeded(_ result: ProcessResult) {
+      switch (result.exitStatus, continueBuildingAfterErrors) {
+      case (.terminated(let code), false) where code != EXIT_SUCCESS:
+         isBuildCancelled = true
+       #if !os(Windows)
+       case (.signalled, _):
+         isBuildCancelled = true
+       #endif
+      default:
+        break
+      }
+    }
   }
 
   /// The work to be done.
@@ -426,8 +448,8 @@ class ExecuteJobRule: LLBuildRule {
     rememberIfInputSucceeded(engine, value: value)
   }
 
+  /// Called when the build engine thinks all inputs are available in order to run the job.
   override func inputsAvailable(_ engine: LLTaskBuildEngine) {
-    // Return early any of the input failed.
     guard allInputsSucceeded else {
       return engine.taskIsComplete(DriverBuildValue.jobExecution(success: false))
     }
@@ -464,6 +486,10 @@ class ExecuteJobRule: LLBuildRule {
   }
 
   private func executeJob(_ engine: LLTaskBuildEngine) {
+    if context.isBuildCancelled {
+      engine.taskIsComplete(DriverBuildValue.jobExecution(success: false))
+      return
+    }
     let context = self.context
     let resolver = context.argsResolver
     let job = myJob
@@ -514,6 +540,8 @@ class ExecuteJobRule: LLBuildRule {
         context.executorDelegate.jobFinished(job: job, result: result, pid: pid)
       }
       value = .jobExecution(success: success)
+
+      context.cancelBuildIfNeeded(result)
     } catch {
       if error is DiagnosticData {
         context.diagnosticsEngine.emit(error)

Tests/SwiftDriverTests/SwiftDriverTests.swift

@@ -1471,6 +1471,34 @@ final class SwiftDriverTests: XCTestCase {
     }
   }
 
+  func testBatchModeContinueAfterErrors() throws {
+    throw XCTSkip("This test requires the fix to honoring -driver-use-frontend-path")
+    struct MockExecutor: DriverExecutor {
+      let resolver = try! ArgsResolver(fileSystem: localFileSystem)
+
+      struct ShouldNeverGetHere: LocalizedError {}
+
+      func execute(job: Job, forceResponseFiles: Bool, recordedInputModificationDates: [TypedVirtualPath : Date]) throws -> ProcessResult {
+        throw ShouldNeverGetHere()
+      }
+      func execute(workload: DriverExecutorWorkload,
+                   delegate: JobExecutionDelegate,
+                   numParallelJobs: Int,
+                   forceResponseFiles: Bool,
+                   recordedInputModificationDates: [TypedVirtualPath : Date]) throws {
+        XCTAssert(workload.continueBuildingAfterErrors)
+      }
+      func checkNonZeroExit(args: String..., environment: [String : String]) throws -> String {
+        throw ShouldNeverGetHere()
+      }
+      func description(of job: Job, forceResponseFiles: Bool) throws -> String {
+        throw ShouldNeverGetHere()
+       }
+    }
+
+    let driver = try Driver(args: ["swiftc", "foo1.swift", "bar1.swift", "-enable-batch-mode", "-driver-use-frontend-path", "/bin/echo"], executor: MockExecutor())
+  }
+
   func testSingleThreadedWholeModuleOptimizationCompiles() throws {
     var driver1 = try Driver(args: ["swiftc", "-whole-module-optimization", "foo.swift", "bar.swift", "-module-name", "Test", "-target", "x86_64-apple-macosx10.15", "-emit-module-interface", "-emit-objc-header-path", "Test-Swift.h", "-emit-private-module-interface-path", "Test.private.swiftinterface"])
     let plannedJobs = try driver1.planBuild()