Hello, during packaging of a new python-img2pdf version I noticed that 2 unit-test cases fail on aarch64. This is caused by zlib.compress() yielding different output on aarch64 and x86-64. Which triggers the failure because the unit-test case just compares the result after compression (it's a small PDF that contains a compressed image - and that PDF is compared against a reference PDF). I checked the aarch64 compress output and it's valid zlib data, i.e. I can decompress it on both aarch64 and x86-64 and get the same decompression result (i.e. the input image data). As far as I understand RFC 1951, it allows for different implementations to yield differing compress output bit-streams - as long as other requirements are met and uncompress(compress(x)) == x (in any combination of implementations). Funnily, the img2pdf author uses Debian, and Debian aarch64 zlib.compress() *does* yield bit-identical output (to x86-64). Perhaps the deviating Fedora aarch64 behaviour is due to different compile options/patches (e.g. some Neon optimization or something like that). The img2pdf author isn't really convinced that zlib may produce different output on different architectures: https://gitlab.mister-muffin.de/josch/img2pdf/issues/51 Any thoughts? Best regards Georg -- 'I have long really held the opinion that the amount of noise which any one can bear undisturbed stands in inverse proportion to his mental capacity, and therefore may be regarded as a pretty fair measure of it.' (Arthur Schopenhauer, The World As Will And Idea. Vol. 2, p.199, 1883) _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://getfedora.org/code-of-conduct.html List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx
