Merge pull request #695 from skrah/append_cxxflags

Allow proper overriding of CXXFLAGS.

Author: izaid

CMakeLists.txt

@@ -120,13 +120,33 @@ string(REPLACE "v" "" DYND_PYTHON_VERSION "${DYND_PYTHON_VERSION_STRING}")
 string(REPLACE "-" ";" DYND_PYTHON_VERSION "${DYND_PYTHON_VERSION}")
 list(GET DYND_PYTHON_VERSION 0 "${DYND_PYTHON_VERSION}")
 
+if(MSVC)
+    set(CMAKE_CXX_FLAGS "-DHAVE_ROUND ${CMAKE_CXX_FLAGS}")
+else()
+    set(CMAKE_BUILD_WITH_INSTALL_RPATH TRUE)
+    if(APPLE)
+        set(CMAKE_CXX_FLAGS "-Wno-unused-parameter -Wno-unused-function -Wno-error ${CMAKE_CXX_FLAGS}")
+    else()
+        set(CMAKE_CXX_FLAGS "-Wno-error ${CMAKE_CXX_FLAGS}")
+    endif()
+endif()
+
 if(MSVC)
     # Treat warnings as errors (-WX does this)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -WX -EHsc")
+    set(CMAKE_CXX_FLAGS "-WX -EHsc ${CMAKE_CXX_FLAGS}")
     if (${CMAKE_CXX_COMPILER_VERSION} VERSION_LESS 18)
         message(FATAL_ERROR "Only MSVC 2013 (Version 18.0) and later are supported by LibDyND. Found version ${CMAKE_CXX_COMPILER_VERSION}.")
     endif ()
 else()
+    if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+        if ("${CMAKE_CXX_COMPILER_VERSION}" VERSION_LESS 4.9)
+            message(FATAL_ERROR "Only GCC 4.9 and later are supported by DyND. Found version ${CMAKE_CXX_COMPILER_VERSION}.")
+        endif()
+        set(CMAKE_CXX_FLAGS "-std=c++14 -fmax-errors=20 ${CMAKE_CXX_FLAGS}")
+    elseif("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
+        set(CMAKE_CXX_FLAGS "-std=c++1y -ferror-limit=20 -Wdocumentation ${CMAKE_CXX_FLAGS}")
+    endif()
+
     if(WIN32)
         # Don't use the -fPIC flag since it is the default on MinGW.
         # Doing so results in a warning that is then raised as an error.
@@ -135,31 +155,12 @@ else()
         if("${CMAKE_SIZEOF_VOID_P}" EQUAL "8")
             # Define MS_WIN64 so that npy_intp has the correct size and
             # the proper module import functions are called on 64 bit Windows.
-            set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D_hypot=hypot -std=c++14 -DMS_WIN64 -g -fomit-frame-pointer -fstrict-aliasing -Wall -Wextra -Werror -Wno-missing-field-initializers")
+            set(CMAKE_CXX_FLAGS "-D_hypot=hypot -std=c++14 -DMS_WIN64 -g -fomit-frame-pointer -fstrict-aliasing -Wall -Wextra -Werror -Wno-missing-field-initializers ${CMAKE_CXX_FLAGS}")
         else()
-            set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D_hypot=hypot -std=c++14 -g -fomit-frame-pointer -fstrict-aliasing -Wall -Wextra -Werror -Wno-missing-field-initializers")
+            set(CMAKE_CXX_FLAGS "-D_hypot=hypot -std=c++14 -g -fomit-frame-pointer -fstrict-aliasing -Wall -Wextra -Werror -Wno-missing-field-initializers ${CMAKE_CXX_FLAGS}")
         endif()
     else()
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g -fomit-frame-pointer -fstrict-aliasing -fPIC -Wall -Wextra -Werror -Wno-missing-field-initializers")
-    endif()
-    if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
-        if ("${CMAKE_CXX_COMPILER_VERSION}" VERSION_LESS 4.9)
-            message(FATAL_ERROR "Only GCC 4.9 and later are supported by DyND. Found version ${CMAKE_CXX_COMPILER_VERSION}.")
-        endif()
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++14 -fmax-errors=20")
-    elseif("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++1y -ferror-limit=20 -Wdocumentation")
-    endif()
-endif()
-
-if(MSVC)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DHAVE_ROUND")
-else()
-    set(CMAKE_BUILD_WITH_INSTALL_RPATH TRUE)
-    if(APPLE)
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unused-parameter -Wno-unused-function -Wno-error")
-    else()
-        set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-error")
+        set(CMAKE_CXX_FLAGS "-g -fomit-frame-pointer -fstrict-aliasing -fPIC -Wall -Wextra -Werror -Wno-missing-field-initializers ${CMAKE_CXX_FLAGS}")
     endif()
 endif()