Allow building Caffe with warnings-as-errors disabled

CMakeLists.txt

@@ -60,6 +60,7 @@ caffe_option(USE_SYSTEMTAP "Build for SystemTap" OFF)
 caffe_option(PERFORMANCE_MONITORING "Build Caffe with PERFORMANCE_MONITORING " OFF)
 #caffe_option(USE_GITHUB_MKLDNN "Download and use MKL-DNN available on github" OFF)
 caffe_option(CODE_COVERAGE "Build with code coverage instrumentation" OFF)
+caffe_option(WARNING_AS_ERROR "Build with warnings treated as errors" ON)
 caffe_option(CO_SIM "Build readonly cpu blob data/diff pycaffe interface" OFF)
 caffe_option(USE_MLSL "Build Caffe with Intel(r) Machine Learning Scaling Library for multinode training" ON)
 caffe_option(ICC_STATIC_BUILD "Build Intel Caffe static link with Intel compiler" OFF)
@@ -87,18 +88,18 @@ if(MSVC)
     endif()
 elseif(UNIX OR APPLE)
   # Linker flags.
-  if( ${CMAKE_CXX_COMPILER_ID} STREQUAL "GNU" OR ${CMAKE_CXX_COMPILER_ID} STREQUAL "Intel") 
+  if( ${CMAKE_CXX_COMPILER_ID} STREQUAL "GNU" OR ${CMAKE_CXX_COMPILER_ID} STREQUAL "Intel")
     # GCC specific flags. ICC is compatible with them.
     set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -z noexecstack -z relro -z now")
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -z noexecstack -z relro -z now")
-  elseif(${CMAKE_CXX_COMPILER_ID} STREQUAL "Clang") 
+  elseif(${CMAKE_CXX_COMPILER_ID} STREQUAL "Clang")
     # In Clang, -z flags are not compatible, they need to be passed to linker via -Wl.
     set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now")
     set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-z,noexecstack -Wl,-z,relro -Wl,-z,now")
   endif()
-  
+
   # Compiler flags.
-  if( ${CMAKE_CXX_COMPILER_ID} STREQUAL "GNU") 
+  if( ${CMAKE_CXX_COMPILER_ID} STREQUAL "GNU")
     # GCC specific flags.
     if(CMAKE_CXX_COMPILER_VERSION VERSION_GREATER 4.9 OR CMAKE_CXX_COMPILER_VERSION VERSION_EQUAL 4.9)
       set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIE -fstack-protector-strong")
@@ -107,11 +108,11 @@ elseif(UNIX OR APPLE)
     else()
       set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIE -fstack-protector")
     endif()
-  elseif(${CMAKE_CXX_COMPILER_ID} STREQUAL "Clang") 
+  elseif(${CMAKE_CXX_COMPILER_ID} STREQUAL "Clang")
     # Clang is compatbile with some of the flags.
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIE -fstack-protector")
-  elseif(${CMAKE_CXX_COMPILER_ID} STREQUAL "Intel" ) 
-    # Same as above, with exception that ICC compilation crashes with -fPIE option, even 
+  elseif(${CMAKE_CXX_COMPILER_ID} STREQUAL "Intel" )
+    # Same as above, with exception that ICC compilation crashes with -fPIE option, even
     # though it uses -pie linker option that require -fPIE during compilation. Checksec
     # shows that it generates correct PIE anyway if only -pie is provided.
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fstack-protector -wd2196")
@@ -122,12 +123,17 @@ elseif(UNIX OR APPLE)
       set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -static-intel")
     endif()
   endif()
-  
+
   # Generic flags.
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fPIC -fno-operator-names -Wformat -Wformat-security -Wall")
   if(NOT CODE_COVERAGE)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -Werror")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
   endif()
+
+  if(WARNING_AS_ERROR)
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Werror")
+  endif()
+
   # Dot not forward c++11 flag to GPU beucause it is not supported
   set( CUDA_PROPAGATE_HOST_FLAGS OFF )
   set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -D_FORTIFY_SOURCE=2")