libarchive: Suppress PathScale compiler warnings

We are not developing libarchive so we do not care about warnings.

Utilities/cmlibarchive/CMakeLists.txt

@@ -49,6 +49,8 @@ SET(SOVERSION "${INTERFACE_VERSION}")
 IF("${CMAKE_C_COMPILER_ID}" MATCHES
     "^(GNU|Clang|XL|VisualAge|SunPro|MIPSpro|HP|Intel)$")
   SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -w")
+ELSEIF("${CMAKE_C_COMPILER_ID}" MATCHES "^(PathScale)$")
+  SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -woffall")
 ELSEIF(BORLAND)
   SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -w-")
 ENDIF()