Re: [ft-devel] [PATCH RFC] src/sfnt/ttsbit0.c: fix broken pointer overflow checks
On Thu, 24 Jan 2013 15:58:14 -0500, Xi Wang said: Many compilers such as gcc and clang optimize away pointer overflow checks `p + n p', because pointer overflow is undefined behavior. And clang can detect signed overflow at runtime if you enable the debug flag -fsanitize=undefined described here: http://clang.llvm.org/docs/UsersManual.html#controlling-code-generation Could be useful to build freetype with that flag and see what it finds... Cheers, -- Sean McBride, B. Eng s...@rogue-research.com Rogue Researchwww.rogue-research.com Mac Software Developer Montréal, Québec, Canada ___ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel
Re: [ft-devel] [PATCH RFC] src/sfnt/ttsbit0.c: fix broken pointer overflow checks
On Fri, 25 Jan 2013 17:48:46 -0500, Xi Wang said: And clang can detect signed overflow at runtime if you enable the debug flag -fsanitize=undefined described here: Yeah, if you have input data to trigger the overflows. Yeah. Ideally freetype would have some unit tests, and some fuzzing. But oh well. Cheers, -- Sean McBride, B. Eng s...@rogue-research.com Rogue Researchwww.rogue-research.com Mac Software Developer Montréal, Québec, Canada ___ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel
[ft-devel] Subpixel Hinting is Broken
Hi all, I've spent the last few hours trying to figure out what was wrong with my code (because I naturally assume that something is messed up with *it*. :D ) Well, it turns out that some recent change to Freetype has broken subpixel hinting. Compile the last release with subpixel hinting and rendering enabled, and run ftview on Courier New (Windows 8 version, but others may work): ftview -r 96 10.0 /usr/share/fonts/windows8/cour.ttf Hit 'L' twice and the down arrow twice, and Esc. Fails = 0. Then, compile the latest git with subpixel hinting and rendering enabled, and repeat. I get 713 fails. I tried reverting certain more obvious things with the changes since the last release, but wasn't able to narrow down the cause. Any ideas on what might have caused this? Thanks, Erik ___ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel
Re: [ft-devel] Subpixel Hinting is Broken
Alexei's latest commit seems to have fixed the issue. On 01/25/2013 10:36 PM, Infinality wrote: Hi all, I've spent the last few hours trying to figure out what was wrong with my code (because I naturally assume that something is messed up with *it*. :D ) Well, it turns out that some recent change to Freetype has broken subpixel hinting. Compile the last release with subpixel hinting and rendering enabled, and run ftview on Courier New (Windows 8 version, but others may work): ftview -r 96 10.0 /usr/share/fonts/windows8/cour.ttf Hit 'L' twice and the down arrow twice, and Esc. Fails = 0. Then, compile the latest git with subpixel hinting and rendering enabled, and repeat. I get 713 fails. I tried reverting certain more obvious things with the changes since the last release, but wasn't able to narrow down the cause. Any ideas on what might have caused this? Thanks, Erik ___ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel
Re: [ft-devel] Subpixel Hinting is Broken
Alexei's latest commit seems to have fixed the issue. Are you aware of the bisecting method? Have a look at `git help bisect'. For such situations it is the easiest way to find out what commit exactly is the problem. Werner ___ Freetype-devel mailing list Freetype-devel@nongnu.org https://lists.nongnu.org/mailman/listinfo/freetype-devel
