[niepce] Fix some warnings

[Hubert Figuière <hub src gnome org>]

commit acedabdd457c3eca113e8b59c0d3752693607eb7
Author: Hubert Figuière <hub figuiere net>
Date:   Sat Jul 30 09:37:08 2016 -0400

    Fix some warnings

 src/fwk/base/geometry.cpp                   |    4 ++--
 src/niepce/modules/darkroom/imagecanvas.cpp |    1 +
 src/niepce/ui/dialogs/importdialog.cpp      |    8 ++++----
 3 files changed, 7 insertions(+), 6 deletions(-)
---
diff --git a/src/fwk/base/geometry.cpp b/src/fwk/base/geometry.cpp
index 5f88739..722caf6 100644
--- a/src/fwk/base/geometry.cpp
+++ b/src/fwk/base/geometry.cpp
@@ -56,9 +56,9 @@ Rect::Rect(const std::string & s)
     }
     int i = 0;
     for_each(v.cbegin(), v.cend(),
-             [&i, this] (const std::string &s) {
+             [&i, this] (const std::string &_s) {
                  try {
-                     _r[i] = std::stoi(s);
+                     _r[i] = std::stoi(_s);
                      i++;
                  }
                  catch(...) {
diff --git a/src/niepce/modules/darkroom/imagecanvas.cpp b/src/niepce/modules/darkroom/imagecanvas.cpp
index 51052fb..f0220f0 100644
--- a/src/niepce/modules/darkroom/imagecanvas.cpp
+++ b/src/niepce/modules/darkroom/imagecanvas.cpp
@@ -130,6 +130,7 @@ bool ImageCanvas::on_draw(const Cairo::RefPtr<Cairo::Context>& context)
         Cairo::RefPtr<Cairo::ImageSurface> img_s;
 
         int img_w, img_h;
+        img_w = img_h = 0;
         double scale = 1.0;
 
         if(m_image->get_status() != ncr::Image::status_t::ERROR) {
diff --git a/src/niepce/ui/dialogs/importdialog.cpp b/src/niepce/ui/dialogs/importdialog.cpp
index 211c855..bf0209a 100644
--- a/src/niepce/ui/dialogs/importdialog.cpp
+++ b/src/niepce/ui/dialogs/importdialog.cpp
@@ -153,11 +153,11 @@ void ImportDialog::setToImport(const Glib::ustring & f)
     if(source_content.get()) {
         auto list_to_import = m_importer->getSourceContent();
 
-        for(const auto & f : list_to_import) {
-            DBG_OUT("selected %s", f->name().c_str());
+        for(const auto & _f : list_to_import) {
+            DBG_OUT("selected %s", _f->name().c_str());
             Gtk::TreeIter iter = m_images_list_model->append();
-            iter->set_value(m_grid_columns.filename, Glib::ustring(f->name()));
-            iter->set_value(m_grid_columns.file, std::move(f));
+            iter->set_value(m_grid_columns.filename, Glib::ustring(_f->name()));
+            iter->set_value(m_grid_columns.file, std::move(_f));
         }
     }
 }