build: add MKLDNN_PRODUCT_BUILD_MODE option

MKLDNN_PRODUCT_BUILD_MODE=ON (default): warnings are errors
MKLDNN_PRODUCT_BUILD_MODE=OFF         : warnings are warnings

cmake/options.cmake

@@ -128,6 +128,15 @@ set(VTUNEROOT "" CACHE STRING
 # Miscellaneous
 # =============
 
+option(BENCHDNN_USE_RDPMC
+    "enables rdpms counter to report precise cpu frequency in benchdnn.
+     CAUTION: may not work on all cpus (hence disabled by default)"
+    OFF) # disabled by default
+
+# =============
+# Developer flags
+# =============
+
 set(MKLDNN_USE_CLANG_SANITIZER "" CACHE STRING
     "instructs build system to use a Clang sanitizer. Possible values:
     Address: enables MemorySanitizer
@@ -136,8 +145,7 @@ set(MKLDNN_USE_CLANG_SANITIZER "" CACHE STRING
     Undefined: enables UndefinedBehaviourSanitizer
     This feature is experimental and is only available on Linux.")
 
-
-option(BENCHDNN_USE_RDPMC
-    "enables rdpms counter to report precise cpu frequency in benchdnn.
-     CAUTION: may not work on all cpus (hence disabled by default)"
-    OFF) # disabled by default
+option(MKLDNN_PRODUCT_BUILD_MODE
+    "Enables/disables product build mode. For example,
+    setting MKLDNN_PRODUCT_BUILD_MODE=OFF makes warnings non-fatal"
+    ON)

cmake/platform.cmake

@@ -22,6 +22,8 @@ if(platform_cmake_included)
 endif()
 set(platform_cmake_included true)
 
+include("cmake/utils.cmake")
+
 add_definitions(-DMKLDNN_DLL -DMKLDNN_DLL_EXPORTS)
 
 # UNIT8_MAX-like macros are a part of the C99 standard and not a part of the
@@ -58,7 +60,8 @@ if(MSVC)
         append(CMAKE_CCXX_FLAGS "-Wno-pass-failed")
     endif()
 elseif(UNIX OR MINGW)
-    append(CMAKE_CCXX_FLAGS "-Wall -Werror -Wno-unknown-pragmas")
+    append(CMAKE_CCXX_FLAGS "-Wall -Wno-unknown-pragmas")
+    append_if_product(CMAKE_CCXX_FLAGS "-Werror")
     append(CMAKE_CCXX_FLAGS "-fvisibility=internal")
     append(CMAKE_C_FLAGS "-std=c99")
     append(CMAKE_CXX_FLAGS "-std=c++11 -fvisibility-inlines-hidden")

cmake/utils.cmake

@@ -22,6 +22,8 @@ if(utils_cmake_included)
 endif()
 set(utils_cmake_included true)
 
+include("cmake/options.cmake")
+
 # Register new executable/test
 #   name -- name of the executable
 #   srcs -- list of source, if many must be enclosed with ""
@@ -45,6 +47,20 @@ macro(append var value)
     set(${var} "${${var}} ${value}")
 endmacro()
 
+# Append to a variable if building a product build (as opposed to a developer
+# build that is detected via the MKLDNN_PRODUCT_BUILD_MODE option)
+macro(append_if_product var value)
+    if(MKLDNN_PRODUCT_BUILD_MODE)
+        append(${var} "${value}")
+    endif()
+endmacro()
+
+if(MKLDNN_PRODUCT_BUILD_MODE)
+    message(STATUS "This is a product build")
+else()
+    message(WARNING "This is a developer build")
+endif()
+
 # Set variable depending on condition:
 #   var = cond ? val_if_true : val_if_false
 macro(set_ternary var condition val_if_true val_if_false)