Fix compiler errors

SConstruct

@@ -2071,7 +2071,7 @@ if not preconfigured:
         # Common flags for g++/clang++ CXX compiler.
         # TODO: clean up code more to make -Wextra -Wsign-compare -Wsign-conversion -Wconversion viable
         # -Wfloat-equal -Wold-style-cast -Wexit-time-destructors -Wglobal-constructors -Wreserved-id-macro -Wheader-hygiene -Wmissing-noreturn
-        common_cxx_flags = '-fvisibility=hidden -fvisibility-inlines-hidden -Wall %s %s -ftemplate-depth-300 -Wsign-compare ' % (env['WARNING_CXXFLAGS'], pthread)
+        common_cxx_flags = '-Wall %s %s -ftemplate-depth-300 -Wsign-compare ' % (env['WARNING_CXXFLAGS'], pthread)
 
         if 'clang++' in env['CXX']:
             common_cxx_flags += ' -Wno-unsequenced  -Wtautological-compare -Wheader-hygiene '

include/mapnik/agg_renderer.hpp

@@ -196,6 +196,7 @@ class MAPNIK_DECL agg_renderer : public feature_style_processor<agg_renderer<T0>
     void setup(Map const& m, buffer_type& pixmap);
 };
 
+extern template class MAPNIK_DECL feature_style_processor<agg_renderer<image_rgba8>>;
 extern template class MAPNIK_DECL agg_renderer<image<rgba8_t>>;
 
 } // namespace mapnik

include/mapnik/cairo/cairo_renderer.hpp

@@ -137,6 +137,7 @@ class MAPNIK_DECL cairo_renderer : public feature_style_processor<cairo_renderer
     void setup(Map const& m);
 };
 
+extern template class MAPNIK_DECL feature_style_processor<cairo_renderer<cairo_ptr>>;  
 extern template class MAPNIK_DECL cairo_renderer<cairo_ptr>;
 
 } // namespace mapnik

include/mapnik/feature_style_processor.hpp

@@ -47,7 +47,7 @@ struct layer_rendering_material;
 enum eAttributeCollectionPolicy { DEFAULT = 0, COLLECT_ALL = 1 };
 
 template<typename Processor>
-class feature_style_processor
+class MAPNIK_DECL feature_style_processor
 {
   public:
     explicit feature_style_processor(Map const& m, double scale_factor = 1.0);