ENH: Handle coverage errors

Source/cmCTest.cxx

@@ -745,7 +745,10 @@ int cmCTest::ProcessTests()
   if ( m_Tests[COVERAGE_TEST] || m_Tests[ALL_TEST] )
     {
     this->UpdateCTestConfiguration();
-    this->CoverageHandler->CoverageDirectory(this);
+    if (this->CoverageHandler->CoverageDirectory(this))
+      {
+      res |= cmCTest::COVERAGE_ERRORS;
+      }
     }
   if ( m_Tests[MEMCHECK_TEST] || m_Tests[ALL_TEST] )
     {

Source/cmCTest.h

@@ -133,7 +133,8 @@ public:
     CONFIGURE_ERRORS = 0x02,
     BUILD_ERRORS = 0x04,
     TEST_ERRORS = 0x08,
-    MEMORY_ERRORS = 0x10
+    MEMORY_ERRORS = 0x10,
+    COVERAGE_ERRORS = 0x20
   };
 
   int GenerateNotesFile(const char* files);