Description: Set compiler flags

Respect CFLAGS,CXXFLAGS,LDFLAGS (security hardening etc.)
Be verbose
Disable non-policy-compliant instruction set assumptions (slows the
OpenCL compiler by ~few%, no effect on OpenCL execution speed)

Author: Simon Richter <sjr@debian.org>,Rebecca Palmer <rebecca_palmer@zoho.com>
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,7 +31,6 @@ INCLUDE_DIRECTORIES(${CMAKE_CURRENT_BINA

 INCLUDE (FindPkgConfig)

-SET(CMAKE_VERBOSE_MAKEFILE "false")
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/CMake/")
 INCLUDE (GNUInstallDirs OPTIONAL)
 # support old CMake without GNUInstallDirs
@@ -73,9 +72,9 @@ ADD_DEFINITIONS(-DGEN7_SAMPLER_CLAMP_BOR

 # compiler flag setting
 if (COMPILER STREQUAL "GCC")
-  set (CMAKE_C_CXX_FLAGS "${CMAKE_C_CXX_FLAGS} -funroll-loops -fstrict-aliasing -msse2 -msse3 -mssse3 -msse4.1 -fPIC -Wall -mfpmath=sse -Wcast-align -Wl,-E")
+  set (CMAKE_C_CXX_FLAGS "${CMAKE_C_CXX_FLAGS} -funroll-loops -fstrict-aliasing -fPIC -Wall -Wcast-align -Wl,-E")
 elseif (COMPILER STREQUAL "CLANG")
-  set (CMAKE_C_CXX_FLAGS "${CMAKE_C_CXX_FLAGS} -funroll-loops -fstrict-aliasing -msse2 -msse3 -mssse3 -msse4.1 -fPIC -Wall")
+  set (CMAKE_C_CXX_FLAGS "${CMAKE_C_CXX_FLAGS} -funroll-loops -fstrict-aliasing -fPIC -Wall")
 elseif (COMPILER STREQUAL "ICC")
   set (CMAKE_C_CXX_FLAGS "${CMAKE_C_CXX_FLAGS}  -wd2928 -Wall -fPIC -fstrict-aliasing -fp-model fast -msse4.1 -Wl,-E")
 endif ()
--- a/backend/src/sys/platform.hpp
+++ b/backend/src/sys/platform.hpp
@@ -41,15 +41,6 @@
 #define __X86__
 #endif

-/* We require SSE ... */
-#ifndef __SSE__
-#define __SSE__
-#endif
-
-/* ... and SSE2 */
-#ifndef __SSE2__
-#define __SSE2__
-#endif

 #if defined(_INCLUDED_IMM)
 // #define __AVX__