From ae2ee043c7b510d43b4b0f90a09e63904382edd9 Mon Sep 17 00:00:00 2001
From: Adam Williamson <awilliam@redhat.com>
Date: Tue, 10 Jan 2017 13:57:16 -0800
Subject: [PATCH] Use reliable int type for mesh size in draw_quad_mesh (#7788)

In the agg backend, `PyRendererAgg.draw_quad_mesh` takes mesh
dimension arguments (`mesh_width` and `mesh_height`). When
converting those from Python to C, we were declaring the C
types as `size_t`, but converting from Python using the 'I'
format specifier, which converts a Python integer to a C
unsigned int. This isn't safe, because `size_t` is not
necessarily the same size as an int. On Fedora with GCC, for
instance, `size_t` is an alias for long unsigned int.

On LE arches this usually won't cause a problem, but on a BE
arch where `size_t` isn't an int type, the mismatch causes
rendering errors (see #7788).

This addresses the problem by just changing the types for these
values to be `unsigned int` instead.
---
 src/_backend_agg.h           | 8 ++++----
 src/_backend_agg_wrapper.cpp | 4 ++--
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/_backend_agg.h b/src/_backend_agg.h
index 0265647cb..53b73f179 100644
--- a/src/_backend_agg.h
+++ b/src/_backend_agg.h
@@ -182,8 +182,8 @@ class RendererAgg
     template <class CoordinateArray, class OffsetArray, class ColorArray>
     void draw_quad_mesh(GCAgg &gc,
                         agg::trans_affine &master_transform,
-                        size_t mesh_width,
-                        size_t mesh_height,
+                        unsigned int mesh_width,
+                        unsigned int mesh_height,
                         CoordinateArray &coordinates,
                         OffsetArray &offsets,
                         agg::trans_affine &offset_trans,
@@ -1148,8 +1148,8 @@ class QuadMeshGenerator
 template <class CoordinateArray, class OffsetArray, class ColorArray>
 inline void RendererAgg::draw_quad_mesh(GCAgg &gc,
                                         agg::trans_affine &master_transform,
-                                        size_t mesh_width,
-                                        size_t mesh_height,
+                                        unsigned int mesh_width,
+                                        unsigned int mesh_height,
                                         CoordinateArray &coordinates,
                                         OffsetArray &offsets,
                                         agg::trans_affine &offset_trans,
diff --git a/src/_backend_agg_wrapper.cpp b/src/_backend_agg_wrapper.cpp
index f6ed42bcd..4806feda0 100644
--- a/src/_backend_agg_wrapper.cpp
+++ b/src/_backend_agg_wrapper.cpp
@@ -390,8 +390,8 @@ static PyObject *PyRendererAgg_draw_quad_mesh(PyRendererAgg *self, PyObject *arg
 {
     GCAgg gc;
     agg::trans_affine master_transform;
-    size_t mesh_width;
-    size_t mesh_height;
+    unsigned int mesh_width;
+    unsigned int mesh_height;
     numpy::array_view<const double, 3> coordinates;
     numpy::array_view<const double, 2> offsets;
     agg::trans_affine offset_trans;
-- 
2.11.0