Merge pull request swiftlang#1502 from tshortli/check-dwarf-version-supported

Only specify -dwarf-version if the frontend supports it

Author: tshortli

Sources/SwiftDriver/Jobs/FrontendJobHelpers.swift

@@ -197,7 +197,9 @@ extension Driver {
  try commandLine.appendLast(in: .g, from: &parsedOptions)
  if debugInfo.level != nil {
  commandLine.appendFlag("-debug-info-format=\(debugInfo.format)")
- commandLine.appendFlag("-dwarf-version=\(debugInfo.dwarfVersion)")
+ if isFrontendArgSupported(.dwarfVersion) {
+ commandLine.appendFlag("-dwarf-version=\(debugInfo.dwarfVersion)")
+ }
  }
  try commandLine.appendLast(.importUnderlyingModule, from: &parsedOptions)
  try commandLine.appendLast(.moduleCachePath, from: &parsedOptions)

Tests/SwiftDriverTests/SwiftDriverTests.swift

@@ -582,17 +582,29 @@ final class SwiftDriverTests: XCTestCase {
  $1.expect(.error("invalid value '6' in '-dwarf-version="))
  }
 
- try assertNoDriverDiagnostics(args: "swiftc", "foo.swift", "-emit-module", "-g", "-debug-info-format=dwarf", "-dwarf-version=4") { driver in
- let jobs = try driver.planBuild()
- XCTAssertTrue(jobs[0].commandLine.contains(.flag("-dwarf-version=4")))
- }
-
  try assertNoDriverDiagnostics(args: "swiftc", "foo.swift", "-g", "-c", "-file-compilation-dir", ".") { driver in
  let jobs = try driver.planBuild()
  XCTAssertTrue(jobs[0].commandLine.contains(.flag("-file-compilation-dir")))
  XCTAssertTrue(jobs[0].commandLine.contains(.flag(".")))
  }
 
+ try assertNoDriverDiagnostics(args: "swiftc", "foo.swift", "-c", "-file-compilation-dir", ".") { driver in
+ let jobs = try driver.planBuild()
+ XCTAssertFalse(jobs[0].commandLine.contains(.flag("-file-compilation-dir")))
+ }
+ }
+
+ func testDwarfVersionSetting() throws {
+ let driver = try Driver(args: ["swiftc", "foo.swift"])
+ guard driver.isFrontendArgSupported(.dwarfVersion) else {
+ throw XCTSkip("Skipping: compiler does not support '-dwarf-version'")
+ }
+
+ try assertNoDriverDiagnostics(args: "swiftc", "foo.swift", "-emit-module", "-g", "-debug-info-format=dwarf", "-dwarf-version=4") { driver in
+ let jobs = try driver.planBuild()
+ XCTAssertTrue(jobs[0].commandLine.contains(.flag("-dwarf-version=4")))
+ }
+
  try assertNoDriverDiagnostics(args: "swiftc", "foo.swift", "-g", "-c", "-target", "x86_64-apple-macosx10.10") { driver in
  let jobs = try driver.planBuild()
  XCTAssertTrue(jobs[0].commandLine.contains(.flag("-dwarf-version=2")))
@@ -625,11 +637,6 @@ final class SwiftDriverTests: XCTestCase {
  let jobs = try driver.planBuild()
  XCTAssertTrue(jobs[0].commandLine.contains(.flag("-dwarf-version=4")))
  }
-
- try assertNoDriverDiagnostics(args: "swiftc", "foo.swift", "-c", "-file-compilation-dir", ".") { driver in
- let jobs = try driver.planBuild()
- XCTAssertFalse(jobs[0].commandLine.contains(.flag("-file-compilation-dir")))
- }
  }
 
  func testCoverageSettings() throws {