[Spice-devel] [PATCH spice-common] canvas: Prevent some error compiling spice-gtk

[Frediano Ziglio]

Due to different warning setting some GCC reports:

In file included from ../spice-common/common/sw_canvas.c:27:0,
                 from client_sw_canvas.c:20:
../spice-common/common/canvas_base.c: In function ‘canvas_get_lz’:
../spice-common/common/canvas_base.c:768:13: error: ‘palette’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
             free(palette);
             ^~~~~~~~~~~~~
../spice-common/common/canvas_base.c:764:9: error: variable ‘free_palette’ might be clobbered by ‘longjmp’ or ‘vfork’ [-Werror=clobbered]
     int free_palette = FALSE;
         ^~~~~~~~~~~~
cc1: all warnings being treated as errors

Signed-off-by: Frediano Ziglio <fziglio at redhat.com>
---
 common/canvas_base.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/common/canvas_base.c b/common/canvas_base.c
index 42f0eea..90d1d38 100644
--- a/common/canvas_base.c
+++ b/common/canvas_base.c
@@ -754,14 +754,14 @@ static pixman_image_t *canvas_get_lz(CanvasBase *canvas, SpiceImage *image,
     uint8_t    *decomp_buf = NULL;
     pixman_format_code_t pixman_format;
     LzImageType type, as_type;
-    SpicePalette *palette;
+    SpicePalette *palette = NULL;
     int n_comp_pixels;
     int width;
     int height;
     int top_down;
     int stride_encoded;
     int stride;
-    int free_palette = FALSE;
+    volatile int free_palette = FALSE;
 
     if (setjmp(lz_data->jmp_env)) {
         if (free_palette)  {
@@ -781,7 +781,9 @@ static pixman_image_t *canvas_get_lz(CanvasBase *canvas, SpiceImage *image,
         spice_return_val_if_fail(image->u.lz_plt.data->num_chunks == 1, NULL); /* TODO: Handle chunks */
         comp_buf = image->u.lz_plt.data->chunk[0].data;
         comp_size = image->u.lz_plt.data->chunk[0].len;
-        palette = canvas_get_localized_palette(canvas, image->u.lz_plt.palette, image->u.lz_plt.palette_id, image->u.lz_plt.flags, &free_palette);
+        palette = canvas_get_localized_palette(canvas, image->u.lz_plt.palette,
+                                               image->u.lz_plt.palette_id, image->u.lz_plt.flags,
+                                               (int*) &free_palette);
     } else {
         spice_warn_if_reached();
         return NULL;
-- 
2.14.3