diff --git a/SConstruct b/SConstruct
index 86f8415b4..80265840d 100644
--- a/SConstruct
+++ b/SConstruct
@@ -1755,8 +1755,8 @@ if not preconfigured:
             env.Append(CPPDEFINES = ndebug_defines)
 
         # Common flags for g++/clang++ CXX compiler.
-        # TODO: clean up code more to make -Wsign-conversion -Wconversion viable
-        common_cxx_flags = '-Wall -Wsign-compare -Wshadow %s %s -ftemplate-depth-300 ' % (env['WARNING_CXXFLAGS'], pthread)
+        # TODO: clean up code more to make -Wsign-conversion -Wconversion -Wshadow viable
+        common_cxx_flags = '-Wall -Wsign-compare %s %s -ftemplate-depth-300 ' % (env['WARNING_CXXFLAGS'], pthread)
 
         # https://github.com/mapnik/mapnik/issues/1835
         if sys.platform == 'darwin' and env['CXX'] == 'g++':
diff --git a/include/mapnik/grid/grid.hpp b/include/mapnik/grid/grid.hpp
index e9d7e85c1..56b67deaf 100644
--- a/include/mapnik/grid/grid.hpp
+++ b/include/mapnik/grid/grid.hpp
@@ -83,9 +83,9 @@ public:
 
     void clear();
 
-    inline void painted(bool painted)
+    inline void painted(bool is_painted)
     {
-        painted_ = painted;
+        painted_ = is_painted;
     }
 
     inline bool painted() const