yes, how true. On Tue, 2 Apr 2019 at 18:22, Devon H. O'Dell <devon.od...@gmail.com> wrote:
> Also worth noting that any padding bits are zeroed as well for > aggregate and union types. Not just setting all pointer values to NULL > and arithmetic types to positive or unsigned zero. > > Op di 2 apr. 2019 om 08:17 schreef Skip Tavakkolian > <skip.tavakkol...@gmail.com>: > > > > like this: > > > > #include <u.h> > > #include <stdio.h> > > > > struct option { > > int n; > > char *s; > > int flags; > > }; > > > > > > int main(void) > > { > > struct option opt = { 1, "test" }; > > static struct option opt2; > > > > printf("%d %s %x\n", opt.n, opt.s, opt.flags); > > printf("%x\n", opt2.flags); > > return 0; > > } > > > > > > On Tue, Apr 2, 2019 at 8:02 AM Skip Tavakkolian < > skip.tavakkol...@gmail.com> wrote: > >> > >> I interpret it as: initialize it like a static variable. > >> > >> On Tue, Apr 2, 2019 at 7:53 AM Kyohei Kadota <lu...@lufia.org> wrote: > >>> > >>> Thank you for a reply. > >>> > >>> I read spec on > http://www.open-std.org/jtc1/sc22/WG14/www/docs/n1256.pdf > >>> then I'm confusing. > >>> This spec describes Initialization: > >>> > >>> > 6.7.8 Initialization, p127 > >>> > > >>> > 19 The initialization shall occur in initializer list order, each > initializer provided for a > >>> > particular subobject overriding any previously listed initializer > for the same subobject;132) > >>> > all subobjects that are not initialized explicitly shall be > initialized implicitly the same as > >>> > objects that have static storage duration. > >>> > >>> What is "be initialized implicitly the same as objects that have > >>> static storage duration" mean? > >>> > >>> 2019年4月2日(火) 9:27 Jeremy O'Brien <neut...@fastmail.com>: > >>> > > >>> > On Mon, Apr 1, 2019, at 11:33, Kyohei Kadota wrote: > >>> > > Hi, 9fans. I use 9legacy. > >>> > > > >>> > > About below program, I expected that flags field will initialize to > >>> > > zero but the value of flags was a garbage, ex, "f8f7". > >>> > > Is this expected? > >>> > > > >>> > > ``` > >>> > > #include <stdio.h> > >>> > > > >>> > > struct option { > >>> > > int n; > >>> > > char *s; > >>> > > int flags; > >>> > > }; > >>> > > > >>> > > int > >>> > > main(void) > >>> > > { > >>> > > struct option opt = {1, "test"}; > >>> > > printf("%d %s %x\n", opt.n, opt.s, opt.flags); > >>> > > return 0; > >>> > > } > >>> > > ``` > >>> > > > >>> > > > >>> > > >>> > According to C99: "If an object that has automatic storage duration > is not initialized explicitly, its value is indeterminate." > >>> > > >>> > Stack variable == automatic storage duration. This appears to be > correct behavior to me. > >>> > > >>> > >