-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 12/18/2016 07:54 PM, Nick Coghlan wrote: > On 18 December 2016 at 18:31, Serhiy Storchaka <storch...@gmail.com> > wrote: > >> Later I'm planning following changes: >> >> * Add the const qualifier to the result of functions that return >> references to internal representation of immutable objects, like >> PyBytes_AS_STRING() or PyUnicode_DATA(). While CPython internally >> can modify the content of immutable objets, this is very dangerous, >> because this can invalidates invariants and cached values. >> Third-party code shouldn't do this. >> >> * Add the const qualifier to the format field of Py_buffer. It is a >> reference to C string literal or to the content of bytes object. >> Mutating its content is an error. Only _testbuffer overuses the >> format field of internal Py_buffer object for owning a reference to >> allocated memory. But this is not leaked outside. >> >> What are you think about this? >> > > As long as it's on the default branch with appropriate notes in the C > porting section of the 3.7 What's New, turning these kinds of runtime > errors into compilation errors sounds like the right thing to do to > me. > > One key aspect from my perspective is that code that is updated to > correctly declare the destination storage as a const pointer will > still compile against the old API variants that return a mutable > pointer, so any problems this finds in third party code are likely to > be resolved for older 3.x releases as well.
Agreed. Anything the compiler ralfs on after adding 'const' (where the actual target must be immutable) already had the fuse smoldering. FWIW I help maintain some *old* C extensions (fifteen+ years and counting), and am as likely to be affected as anyone. Tres - -- =================================================================== Tres Seaver +1 540-429-0999 tsea...@palladion.com Palladion Software "Excellence by Design" http://palladion.com -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJYVz1oAAoJEPKpaDSJE9HYNc0P/2ZfDQeWmecy/deL4mqvLh42 iZuyyXoYmsEvHWgTL1gCOK3isUAKn5MMDAk79ezGkbmrmerxV0EVCrIsQMaCBuhY ypWxsPHa1nUpJpTuziHi452ETDq606nDgUXJnNUtR1xqVlFNpNskTYdexkxv4K5W E+ANwNvE+/YZN7t8KmIcR8pczRGhWJ5X67+etG0KlJ0mDR13RIpUZs7OfTFsXRi1 YHYgI1uKKkphB/KdPxeQfN4G5CgiRK3fJ8sQO2ojJKt3xMqPJcmGG0KIHZi0waXA Uqh+ukKE1tWDdBPYubv+4nlrtWQye6kX9gUu/gXYXM9C7h3u9B9otYXblNGqZAol q6+QfnSmOCZkGeaGw+Gwzz+B2yQcz4phuaz1AirtYUA66s0vbLuKi+SNiVei2gzn M/xd1HpZOxFVk/QkZYHlOW0k2F8o73ecWSONo1xTgi7pdjDrAALhbQ+7Z/dBHn0i 474VoRXcEqVwST87CqbEXyW82GexOppPGqi0jgeAFWJtb0HytuLv21l/h7XgX/TV lmrxGAh6VGl2FOIQolgSNKaVQHsxh2xDq8lL7hGgXuDcI4fD3d+p6bu3tpN6nXMA b4k0TAry7PfKASk0MJgU9aZCSFulDR8ghnx+nUte0OrDdd+nqaovtZcT1Y52glU/ FBw00PcU9+MWZ+zlQNfs =/M++ -----END PGP SIGNATURE----- _______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
