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;

To compile and install SDL:

    1.  Run './configure; make; make install'

        If you are compiling for Windows using gcc, read the FAQ at:
        http://www.libsdl.org/faq.php?action=listentries&category=4#42

        If you are compiling using Visual C++ on Win32, you should read
        the file VisualC.html

    2.  Look at the example programs in ./test, and check out the HTML
        documentation in ./docs to see how to use the SDL library.

    3.  Join the SDL developer mailing list by sending E-mail to
    	sdl-request@libsdl.org
        and put "subscribe" in the subject of the message.

        Or alternatively you can use the web interface:
            http://www.libsdl.org/mailing-list.php

That's it!
Sam Lantinga <slouken@libsdl.org>