tests: fix test_compiled.address_sanitizer_coverage test

Restore building of the sanitizer-coverage executable in CMake, and just
skip the test if it was not built with clang.

The original code made it hard to understand the purpose of the test.

tests/CMakeLists.txt

@@ -159,11 +159,11 @@ add_executable(fork+exec fork/fork+exec.c)
 add_executable(thread-test threads/thread-main.c)
 target_link_libraries(thread-test ${CMAKE_THREAD_LIBS_INIT})
 
-#if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
-# add_executable(sanitizer-coverage sanitizer-coverage.c)
-# set_target_properties(sanitizer-coverage PROPERTIES COMPILE_FLAGS "-g -fsanitize=address -fsanitize-coverage=bb")
-# set_target_properties(sanitizer-coverage PROPERTIES LINK_FLAGS "-fsanitize=address -fsanitize-coverage=bb")
-#endif (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+ add_executable(sanitizer-coverage sanitizer-coverage.c)
+ set_target_properties(sanitizer-coverage PROPERTIES COMPILE_FLAGS "-g -fsanitize=address -fsanitize-coverage=bb")
+ set_target_properties(sanitizer-coverage PROPERTIES LINK_FLAGS "-fsanitize=address -fsanitize-coverage=bb")
+endif (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
 
 add_executable (pie pie.c)
 if (CMAKE_VERSION VERSION_LESS "2.8.9")

tests/tools/test_compiled.py

@@ -568,8 +568,8 @@ class address_sanitizer_coverage(libkcov.TestCase):
  @unittest.expectedFailure
  def runTest(self):
  if not os.path.isfile(self.binaries + "/sanitizer-coverage"):
- self.write_message("Clang-only")
- assert False
+ self.skipTest("Clang only")
+
  rv, o = self.do(
  self.kcov
  + " --clang "