From mboxrd@z Thu Jan 1 00:00:00 1970 From: Fabrice Fontaine Date: Fri, 28 May 2021 17:26:26 +0200 Subject: [Buildroot] [PATCH 1/1] package/capnproto: fix build on riscv32 In-Reply-To: <7eca6978-c70c-cb04-00f3-3ddad374e7f5@mind.be> References: <20210527210402.555334-1-fontaine.fabrice@gmail.com> <20210528065949.GA2170022@sunra> <7eca6978-c70c-cb04-00f3-3ddad374e7f5@mind.be> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net Le ven. 28 mai 2021 ? 17:25, Arnout Vandecappelle a ?crit : > > > > On 28/05/2021 16:33, Fabrice Fontaine wrote: > > Hi Arnout, > > > > Le ven. 28 mai 2021 ? 16:17, Arnout Vandecappelle a ?crit : > >> > >> > >> > >> On 28/05/2021 09:11, Fabrice Fontaine wrote: > >>> Hi Koen, > >>> > >>> Le ven. 28 mai 2021 ? 09:00, Koen Martens a ?crit : > >>>> > >>>> Hi, > >>>> > >>>> Thanks for diving into this. I've had emails about this for months, and briefly > >>>> looked at it, but never found the time to properly figure it out. > >>>> > >>>> I see the patch below is also present upstream. Do you know whether this has > >>>> already been released or when it will be? > >>> I don't know when upstream will release a new version. > >>> However, after digging through a lot of riscv32 build failures on > >>> other packages, I'm not sure that this upstream patch is right > >>> anymore. > >>> Aliasing SYS_futex to SYS_futex_time64 has been rejected by vlc for example: > >>> https://patches.videolan.org/patch/30581/ > >> > >> That patch looks OK to me: > >> > >> +/* 32bit architectures with 64bit time_t do not define __NR_futex syscall */ > >> +#if !defined(SYS_futex) && defined(SYS_futex_time64) > >> +#define SYS_futex SYS_futex_time64 > >> +#endif > >> > >> The comment was "this patch won't work if the userspace ABI uses the > >> 64-bit time_t on a 32-bit ISA that did start with 32-bit time_t" - but that's > >> not true. On a 32-bit ISA that did start with 32-bit time_t, SYS_futex will be > >> defined (or SYS_foo is not properly exported by libc and then SYS_futex_time64 > >> isn't defined either). > >> > >> To be really safe, you should maybe also check that __TIMESIZE == 64 [1] - but > >> that may break on musl or uClibc. > >> > >> Or even better of course would be to patch all code to use the __time64_t > >> instead of time_t everywhere, independent of __TIMESIZE. But even then you'd > >> need fallback to time_t for old libc/kernel. > > Thanks for your feedback, I'll then send a v2 of my patch for vlc to > > fix the build on riscv32 instead of disabling it. > > Well, no, only if upstream vlc is going to accept that approach. OK, then feel free to apply v1 ;-) > > Regards, > Arnout > > >> > >> > >> Regards, > >> Arnout > >> > >> > >> [1] > >> https://www.gnu.org/software/libc/manual/html_node/64_002dbit-time-symbol-handling.html > >> > >> > >> > >> > >> > >>> So another option would be to just disable capnproto on riscv32. > >>>> > >>>> Given that this exact patch is also applied upstream, your patch below seems fine > >>>> to me. > >>>> > >>>> Cheers, > >>>> > >>>> Koen > >>>> > >>>> On Thu, May 27, 2021 at 11:04:02PM +0200, Fabrice Fontaine wrote: > >>>>> Fixes: > >>>>> - http://autobuild.buildroot.org/results/1c1cd4775241ee57d878cad5c978413d4b4a8736 > >>>>> > >>>>> Signed-off-by: Fabrice Fontaine > >>>>> --- > >>>>> ...it-architectures-using-64-bit-time_t.patch | 37 +++++++++++++++++++ > >>>>> 1 file changed, 37 insertions(+) > >>>>> create mode 100644 package/capnproto/0001-mutex-Fix-build-on-32-bit-architectures-using-64-bit-time_t.patch > >>>>> > >>>>> diff --git a/package/capnproto/0001-mutex-Fix-build-on-32-bit-architectures-using-64-bit-time_t.patch b/package/capnproto/0001-mutex-Fix-build-on-32-bit-architectures-using-64-bit-time_t.patch > >>>>> new file mode 100644 > >>>>> index 0000000000..ce70ab8f29 > >>>>> --- /dev/null > >>>>> +++ b/package/capnproto/0001-mutex-Fix-build-on-32-bit-architectures-using-64-bit-time_t.patch > >>>>> @@ -0,0 +1,37 @@ > >>>>> +From e2a05a19e9dc51287e19cc9f11fd91449219e361 Mon Sep 17 00:00:00 2001 > >>>>> +From: Khem Raj > >>>>> +Date: Sun, 15 Nov 2020 12:10:28 -0800 > >>>>> +Subject: [PATCH] mutex: Fix build on 32-bit architectures using 64-bit time_t > >>>>> + > >>>>> +mutex code uses SYS_futex, which it expects from system C library. > >>>>> +in glibc (/usr/include/bits/syscall.h defines it in terms of of NR_futex) > >>>>> +rv32 is using 64bit time_t from get go unlike other 32bit architectures > >>>>> +in glibc, therefore it wont have NR_futex defined but just NR_futex_time64 > >>>>> +this aliases it to NR_futex so that SYS_futex is then defined for rv32 > >>>>> + > >>>>> +Signed-off-by: Khem Raj > >>>>> +[Retrieved from: > >>>>> +https://github.com/capnproto/capnproto/commit/e2a05a19e9dc51287e19cc9f11fd91449219e361] > >>>>> +Signed-off-by: Fabrice Fontaine > >>>>> +--- > >>>>> + c++/src/kj/mutex.c++ | 6 ++++++ > >>>>> + 1 file changed, 6 insertions(+) > >>>>> + > >>>>> +diff --git a/c++/src/kj/mutex.c++ b/c++/src/kj/mutex.c++ > >>>>> +index c81cead7b..e1594b117 100644 > >>>>> +--- a/c++/src/kj/mutex.c++ > >>>>> ++++ b/c++/src/kj/mutex.c++ > >>>>> +@@ -39,7 +39,13 @@ > >>>>> + > >>>>> + #ifndef SYS_futex > >>>>> + // Missing on Android/Bionic. > >>>>> ++#ifdef __NR_futex > >>>>> + #define SYS_futex __NR_futex > >>>>> ++#elif defined(SYS_futex_time64) > >>>>> ++#define SYS_futex SYS_futex_time64 > >>>>> ++#else > >>>>> ++#error "Need working SYS_futex" > >>>>> ++#endif > >>>>> + #endif > >>>>> + > >>>>> + #ifndef FUTEX_WAIT_PRIVATE > >>>>> -- > >>>>> 2.30.2 > >>>>> > >>> Best Regards, > >>> > >>> Fabrice > >>> _______________________________________________ > >>> buildroot mailing list > >>> buildroot at busybox.net > >>> http://lists.busybox.net/mailman/listinfo/buildroot > >>> > > Best Regards, > > > > Fabrice > > Best Regards, Fabrice