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Re: possible opendir bug?
>> I'm not sure to what extent use of uninitialized memory is
>> considered a bug when, as here, the code is correct regardless of
>> what value it contains.
> It is a bug (and should be detected in builds with proper -fsanitize=
> compiler options in -current at least).
There's a -fsanitize= option affecting malloc()ed block contents??
I wonder why it hasn't been picked up already, then.
> Do you have a reproducer handy?
I noticed it with...su, I think it was, but that's just an artifact of
which processes I happened to run after getting the emulator to that
point. Anything that calls opendir() and readdir() on a should trigger
it. Here's a tiny example. This compiles and runs under the emulator,
but when malloc-undefinedness is turned on, it trips.
#include <dirent.h>
int main(void);
int main(void)
{
DIR *d;
struct dirent *e;
d = opendir(".");
if (d) e = readdir(d);
// don't let the above be "optimized" away
(void)((volatile struct dirent *)e)->d_fileno;
return(0);
}
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