[WIP] Pass -gcflags to go build

Author: sue445

_gem/lib/go_gem/mkmf.rb

@@ -38,7 +38,7 @@ def $objs.empty?; false; end
           $(DLLIB): Makefile $(srcdir)/*.go
                   cd $(srcdir); \
                   CGO_CFLAGS='$(INCFLAGS)' CGO_LDFLAGS='#{ldflags}' GOFLAGS='#{goflags}' \
-                    go build -p 4 -buildmode=c-shared -o #{current_dir}/$(DLLIB)
+                    go build -gcflags="all=-N -l" -p 4 -buildmode=c-shared -o #{current_dir}/$(DLLIB)
         MAKEFILE
       end
     end