diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5ccdb6fd0..8ff7c7216 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -269,11 +269,15 @@ if(EXISTS $ENV{GTEST_DIR})
 endif(EXISTS $ENV{GTEST_DIR})
 if(GTEST_DIR)
      message(STATUS "GTEST root folder at ${GTEST_DIR}")
-else()
-     message (STATUS " Googletest has not been found because the environment variable ")
-     message (STATUS " GTEST_DIR is not defined.")
-     message (STATUS " Googletest will be downloaded and built automatically ")
-     message (STATUS " when doing 'make'. ")
+else(GTEST_DIR)
+     find_path(LIBGTEST_DEV_DIR NAMES gtest-all.cc PATHS /usr/src/gtest/src)
+     if(LIBGTEST_DEV_DIR)
+         message (STATUS " Googletest (libgtest-dev package) has been found.")
+     else(LIBGTEST_DEV_DIR)
+         message (STATUS " Googletest has not been found.")
+         message (STATUS " Googletest will be downloaded and built automatically ")
+         message (STATUS " when doing 'make'. ")
+     endif(LIBGTEST_DEV_DIR)
 endif(GTEST_DIR)
 
 
@@ -990,7 +994,7 @@ endif(ENABLE_RTLSDR)
 # Enable C++11 support in GCC
 # For "-std=c++0x"  GCC's support for C++11 see http://gcc.gnu.org/projects/cxx0x.html
 if(CMAKE_COMPILER_IS_GNUCXX AND NOT WIN32)
-     set(MY_CXX_FLAGS "${MY_CXX_FLAGS} -std=c++0x -Wall")  #Add warning flags: For "-Wall" see http://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
+     set(MY_CXX_FLAGS "${MY_CXX_FLAGS} -std=c++0x -Wall -Wextra")  #Add warning flags: For "-Wall" see http://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html
 endif(CMAKE_COMPILER_IS_GNUCXX AND NOT WIN32)
 if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
     set(MY_CXX_FLAGS "${MY_CXX_FLAGS} -std=c++11 -stdlib=libc++ -Wno-c++11-narrowing") 
@@ -1001,19 +1005,12 @@ endif(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
 
 # Processor-architecture related flags
 # See http://gcc.gnu.org/onlinedocs/gcc/i386-and-x86_002d64-Options.html#i386-and-x86_002d64-Options
-# Change to '-mtune=generic' when building for distribution (except when compiling for arm)
 if (NOT ARCH_COMPILER_FLAGS)
   if(CMAKE_COMPILER_IS_GNUCXX AND NOT WIN32)
     if(OS_IS_MACOSX)
       set(ARCH_COMPILER_FLAGS "-march=corei7 -mfpmath=sse")
     else(OS_IS_MACOSX)
-      if(ENABLE_GENERIC_ARCH)
-         if(IS_ARM)
-	        set(ARCH_COMPILER_FLAGS "-mtune=generic-arm")
-	     else(IS_ARM)
-            set(ARCH_COMPILER_FLAGS "-mtune=generic")
-	     endif(IS_ARM)
-      else(ENABLE_GENERIC_ARCH)
+      if(NOT ${ENABLE_GENERIC_ARCH})
          if(IS_ARM) # ARM-specific options (https://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html)
             if(ARM_VERSION STREQUAL "arm")
                # Unknown arm version - try our best to detect
@@ -1024,7 +1021,7 @@ if (NOT ARCH_COMPILER_FLAGS)
          else(IS_ARM)
             set(ARCH_COMPILER_FLAGS "-march=native -mfpmath=sse")
 	     endif(IS_ARM)
-      endif(ENABLE_GENERIC_ARCH)
+      endif(NOT ${ENABLE_GENERIC_ARCH})
     endif(OS_IS_MACOSX)
   endif(CMAKE_COMPILER_IS_GNUCXX AND NOT WIN32)
 endif (NOT ARCH_COMPILER_FLAGS)