Am Mittwoch, 27. Oktober 2021, 11:19:19 MESZ hat Thomas Wolff <t...@towo.net> Folgendes geschrieben:
> I noticed that mintty did not compile anymore after upgrade to gcc 11, > but only on cygwin 32-bit. > I tried to minimize the test case as much as possible without having the > bug vanish, to the attached standalone file. > Compile this with > cc -O2 -Wall -Werror m0.c > and it gives a false positive warning about possible uninitialized data > usage. > While data flow analysis is not perfect, it is weird that this used to > happen on 32 bit but not on 64 bit. > Meanwhile, after updating some other packages (not sure which), but > still the same gcc version, the report on the test case also happens on > 64 bit, while the original, unstripped file, as part of mintty, still > works without error on 64 bit, which is even weirder. > I have not yet had the opportunity to test this on Linux, sorry, so I'm > reporting it here. > Thomas If you mean this warning: m0.c: In function 'do_bidi': m0.c:256:12: error: '*types[0]' may be used uninitialized [-Werror=maybe-uninitialized] This warning is correct, because as far as gcc is concerned, count could be 0, and in this case types[0] will be uninitialized (and doesn't even exist, since it's declared as 'uchar types[count];'). Hannes -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
