Stefan Behnel schrieb am 05.09.2015 um 16:01: > Jeroen Demeyer schrieb am 05.09.2015 um 12:17: >> I noticed that now unsigned constants like >> >> DEF foo = 1 >> >> become 1U in the C source code. >> >> This change (i.e. commit ea6414cd293ba2134c3df5b37b158d8e3db79083) broke >> Sage. I haven't managed yet to actually isolate why this change broke >> something. >> >> Was this change of 1 to 1U intentional? Why was it done? > > Pretty much intentional, yes. I changed it in response to this bug report: > > http://thread.gmane.org/gmane.comp.python.cython.devel/15774 > > The problem with DEF constants is that they are Python values that use > Python semantics in expressions before they eventually get converted back > into literals and inserted into the AST. Specifically, they loose any > literals semantics that they initially had in the source code, including > any information about literal C integer types that contributed to their > value, as in this case. Thus, there isn't really a 'correct' way to write > them out as literals and C might be happy with what we output, or not. > > I guess it might be better to undo this part of the change. Unsigned > literals are usually not the right way to do it in C, definitely not for > everything. We could then maybe apply the usual 32/64 bits heuristic to add > at least L/LL suffixes at need.
Does this look better? https://github.com/cython/cython/commit/2ac9ffbab1e868137bf33bf025eb7a5c7e4707ce It now appends the 'U' suffix only to literals that are used in an unsigned context (e.g. assignment to unsigned variable), and additionally appends L/LL suffixes for integers that might exceed the int/long limits. That's just guessing, but it should generally improve the current handling of literals and DEF expressions. Stefan _______________________________________________ cython-devel mailing list cython-devel@python.org https://mail.python.org/mailman/listinfo/cython-devel
