build: Reintroduce warning flags from autotools

Some of the flags got lost in the meson transition or were demoted from
error flags to warning flags.
This commit reintroduces them.

It also includes fixes for the code that had warnings with those flags.
The big one being -Wshadow.

1 files changed, 3 insertions, 3 deletions

diff --git a/gdk/gdkgltexture.c b/gdk/gdkgltexture.c
index 618aa45f4c..e110b6670b 100644
--- a/gdk/gdkgltexture.c
+++ b/gdk/gdkgltexture.c
@@ -91,10 +91,10 @@ gdk_gl_texture_download (GdkTexture         *texture,
     }
   else
     {
-      GdkSurface *surface;
+      GdkSurface *gl_surface;
 
-      surface = gdk_gl_context_get_surface (self->context);
-      gdk_cairo_draw_from_gl (cr, surface, self->id, GL_TEXTURE, 1, 
+      gl_surface = gdk_gl_context_get_surface (self->context);
+      gdk_cairo_draw_from_gl (cr, gl_surface, self->id, GL_TEXTURE, 1, 
                               area->x, area->y,
                               area->width, area->height);
     }