Date: Thu, 03 Sep 2020 15:36:00 -0400 From: "Stefan O'Rear" <sorear@...tmail.com> To: musl@...ts.openwall.com Subject: Re: [PATCH 02/14] time64: Don't make aliases to nonexistent syscalls On Thu, Sep 3, 2020, at 11:56 AM, Rich Felker wrote: > On Thu, Sep 03, 2020 at 07:22:57AM -0400, Stefan O'Rear wrote: > > riscv32 and future architectures lack the _time32 variants entirely, so > > don't try to use their numbers. > > --- > > src/internal/syscall.h | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/src/internal/syscall.h b/src/internal/syscall.h > > index d5f294d4..66fc4e5c 100644 > > --- a/src/internal/syscall.h > > +++ b/src/internal/syscall.h > > @@ -201,6 +201,7 @@ static inline long __alt_socketcall(int sys, int sock, int cp, long a, long b, l > > #define SYS_sendfile SYS_sendfile64 > > #endif > > > > +#ifdef SYS_timer_settime32 > > #ifndef SYS_timer_settime > > #define SYS_timer_settime SYS_timer_settime32 > > #endif > > @@ -240,6 +241,7 @@ static inline long __alt_socketcall(int sys, int sock, int cp, long a, long b, l > > #ifndef SYS_settimeofday > > #define SYS_settimeofday SYS_settimeofday_time32 > > #endif > > +#endif > > The existing expectation internally in musl is that archs that lack > legacy time32 syscalls have both the unadorned and _time64 macros > defined to the same value. The public headers don't have to be like > that but the internal ones do. See arch/x32/syscall_arch.h which does > it but in the opposite direction. This logic is all tested for x32 and > a big part of the point of that was preparing for rv32 and future > 32-bit archs. > > I'm actually missing how this patch worked as-written, since for > example timer_settime.c unconditionally assumes SYS_timer_settime is > defined, and if it's defined to anything other than the same value as > the time64 version, it will use the value as a fallback. src/internal/syscall.h has two groups of conditional definitions of unadorned syscall numbers, the first of which sets undefined syscalls to the _time32 version, the second of which sets to the _time64 version. So for instance I see no way for the #define SYS_clock_gettime SYS_clock_gettime64 (https://git.musl-libc.org/cgit/musl/tree/src/internal/syscall.h#n250) to execute. -s
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.