[Mesa-dev] [PATCH] mesa: Skip mipmap generation if there is no source image.

[Eric Anholt]

The spec doesn't explicitly mandate this behavior, but it seems like
the only sensible thing to do (as opposed to assertion failing or
segfaulting).

v2: Do the early return before calling into the driver function.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=40308
---
 src/mesa/main/fbobject.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
index f9da54e..c56062a 100644
--- a/src/mesa/main/fbobject.c
+++ b/src/mesa/main/fbobject.c
@@ -2486,6 +2486,7 @@ _mesa_GetFramebufferAttachmentParameterivEXT(GLenum target, GLenum attachment,
 void GLAPIENTRY
 _mesa_GenerateMipmapEXT(GLenum target)
 {
+   struct gl_texture_image *srcImage;
    struct gl_texture_object *texObj;
    GLboolean error;
 
@@ -2532,6 +2533,13 @@ _mesa_GenerateMipmapEXT(GLenum target)
    }
 
    _mesa_lock_texture(ctx, texObj);
+
+   srcImage = _mesa_select_tex_image(ctx, texObj, target, texObj->BaseLevel);
+   if (!srcImage) {
+      _mesa_unlock_texture(ctx, texObj);
+      return;
+   }
+
    if (target == GL_TEXTURE_CUBE_MAP) {
       GLuint face;
       for (face = 0; face < 6; face++)
-- 
1.7.7