Fix to support verilator tests in chisel3 that use MFC to generate unittests

src/main/scala/firrtl/util/BackendCompilationUtilities.scala

@@ -163,6 +163,17 @@ object BackendCompilationUtilities extends LazyLogging {
  def cppToExe(prefix: String, dir: File): ProcessBuilder =
  Seq("make", "-C", dir.toString, "-j", "-f", s"V$prefix.mk", s"V$prefix")
 
+ /** Check for failed unit test using verilator
+ * Failure determined by
+ * - supplied assertion message on stdout
+ * - "Assertion failed" on stderr
+ * - exit code not equal to 0 or 134
+ *
+ * @param prefix program to be run after adding capital "./V" to the front
+ * @param dir working directory for program execution
+ * @param assertionMsg message to look for on stdout
+ * @return true
+ */
  def executeExpectingFailure(
  prefix: String,
  dir: File,
@@ -176,7 +187,11 @@ object BackendCompilationUtilities extends LazyLogging {
  triggered = triggered || (assertionMessageSupplied && line.contains(assertionMsg))
  logger.info(line)
  },
- logger.warn(_)
+ stderrLine => {
+ triggered = triggered || stderrLine
+ .contains("Assertion failed") || (assertionMessageSupplied && stderrLine.contains(assertionMsg))
+ logger.warn(stderrLine)
+ }
  )
  // Fail if a line contained an assertion or if we get a non-zero exit code
  // or, we get a SIGABRT (assertion failure) and we didn't provide a specific assertion message