Fixed bug #33 Mike Frysinger wrote: > with libsdl-1.2.9, some games (like bomberclone) started > segfaulting in Gentoo [...snip...] > the last change in the last hunk: [...snip...] > if i change the statement to read: > (table[which].blit_features & GetBlitFeatures()) == GetBlitFeatures() > bomberclone no longer segfaults on my box Alex Volkov wrote: > The test "(table[which].blit_features & GetBlitFeatures()) == > table[which].blit_features)" is correct, and the previous > "(table[which].cpu_mmx == SDL_HasMMX())" was actually broken. I think there is potentially a slightly different cause of the above problem. During the introduction of the Altivec code, the blit_table struct field 'alpha' got changed from a straightforward enum to a bitmask, which makes perfect sense by itself. However, now the table driven blitter selection code in SDL_CalculateBlitN() can choose the wrong blitters when searching for a NO_ALPHA blitter because of the following code: int a_need = 0; ... (a_need & table[which].alpha) == a_need && When searching through the normal_blit_2[] table, a SET_ALPHA blitter (like Blit_RGB565_ARGB8888) can now be selected instead of a NO_ALPHA one, causing alpha channel bits to appear in a non-alpha destination surface. I suppose this could theoretically be an indirect cause of the segfault mentioned above. I *think* this can be fixed by changing to int a_need = NO_ALPHA;

.TH "SDL_SysWMEvent" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_SysWMEvent\- Platform-dependent window manager event\&.
.SH "DESCRIPTION"
.PP
The system window manager event contains a pointer to system-specific information about unknown window manager events\&. If you enable this event using \fI\fBSDL_EventState()\fP\fR, it will be generated whenever unhandled events are received from the window manager\&. This can be used, for example, to implement cut-and-paste in your application\&. 
.PP
.nf
\f(CWtypedef struct {
         Uint8 type;   /* Always SDL_SysWM */
 } SDL_SysWMEvent;\fR
.fi
.PP
 If you want to obtain system-specific information about the window manager, you can fill the version member of a \fBSDL_SysWMinfo\fR structure (details can be found in \fBSDL_syswm\&.h\fP, which must be included) using the \fBSDL_VERSION()\fP macro found in \fBSDL_version\&.h\fP, and pass it to the function: 
.PP
.sp
\fBint \fBSDL_GetWMInfo\fP\fR(\fBSDL_SysWMinfo *info\fR);
.SH "SEE ALSO"
.PP
\fI\fBSDL_EventState\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00