On Sat, 2011-04-02 at 23:54 +0200, Gerald Pfeifer wrote:
Matteo et al,
there is some code in dlls/d3dx9_36/surface.c which GCC struggles with (in the sense of warning about it), and so do I, so I am wondering whether you can have a look?
Specifically, in point_filter_simple_data we have:
DWORD val = 0, pixel; /* extract source color components */ if(srcformat->type == FORMAT_ARGB) { pixel = dword_from_bytes(srcptr, srcformat->bytes_per_pixel); get_relevant_argb_components(&conv_info, pixel, channels); }So, pixel is uninitialized, except when we have FORMAT_ARGB.
However, directly below we then have
/* recombine the components */ if(destformat->type == FORMAT_ARGB) val = make_argb_color(&conv_info, channels); if(colorkey) { get_relevant_argb_components(&ck_conv_info, pixel, channels);where pixel is passed to get_relevant_argb_components. This is guarded by colorkey, a parameter to this function, so indeed I can see pixel being unused here.
Currently that is not a real problem, as every pixel format has type FORMAT_ARGB (you can see that from the formats array in util.c). Surely the code could be nicer though.
(I'd naively propose a patch like the one below; this may not be sufficient though.)
Gerald
diff --git a/dlls/d3dx9_36/surface.c b/dlls/d3dx9_36/surface.c index a3e6e68..cc36818 100644 --- a/dlls/d3dx9_36/surface.c +++ b/dlls/d3dx9_36/surface.c @@ -701,7 +701,7 @@ static void copy_simple_data(CONST BYTE *src, UINT srcpitch, POINT srcsize, DWORD val = 0;
for(x = 0;x < minwidth;x++) {
DWORD pixel;
DWORD pixel = 0xFFFFFFFF; /* extract source color components */ if(srcformat->type == FORMAT_ARGB) {@@ -768,7 +768,7 @@ static void point_filter_simple_data(CONST BYTE *src, UINT srcpitch, POINT srcsi
for(x = 0;x < destsize.x;x++) { const BYTE *srcptr = bufptr + (x * srcsize.x / destsize.x) * srcformat->bytes_per_pixel;
DWORD val = 0, pixel;
DWORD val = 0, pixel = 0xFFFFFFFF; /* extract source color components */ if(srcformat->type == FORMAT_ARGB) {
That would silence the warnings but it doesn't look to me as the right fix. I think the easiest is to just move the format type checks from copy_simple_data and point_filter_simple_data to D3DXLoadSurfaceFromMemory (which is the only caller) and bail out if the source or the destination format is not FORMAT_ARGB.
I can prepare a patch for that, if you don't feel like giving it a try. Thanks for the heads-up in any case. :)