On 5/16/2020 11:22 AM, Lokesh Vutla via Linuxptp-devel wrote: > Hi Richard, > > On 16/05/20 10:44 PM, Richard Cochran wrote: >> On Sat, May 16, 2020 at 10:35:33PM +0530, Lokesh Vutla wrote: >>> Hi Richard, >>> >>> On 16/05/20 10:24 PM, Richard Cochran wrote: >>>> On Fri, Apr 17, 2020 at 10:00:09AM +0530, Lokesh Vutla wrote: >>>>> phc2pwm.c | 233 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ >>>>> 2 files changed, 237 insertions(+), 2 deletions(-) >>>>> create mode 100644 phc2pwm.c >>>> >>>> I wanted to try this today. There are some issues: >>>> >>>> /home/richard/git/linuxptp/phc2pwm.c: In function ‘main’: >>>> /home/richard/git/linuxptp/phc2pwm.c:222:3: error: ‘period’ may be used >>>> uninitialized in this function [-Werror=maybe-uninitialized] >>>> pwm_chan_set_period(chan, pwm_servo_sample(&ps, ts)); >>>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >>>> /home/richard/git/linuxptp/phc2pwm.c:193:8: error: ‘ptp_dev’ may be used >>>> uninitialized in this function [-Werror=maybe-uninitialized] >>>> clkid = phc_open(ptp_dev); >>>> ~~~~~~^~~~~~~~~~~~~~~~~~~ >>>> /home/richard/git/linuxptp/phc2pwm.c:203:8: error: ‘event_index’ may be >>>> used uninitialized in this function [-Werror=maybe-uninitialized] >>>> err = phc_enable_extts(clkid, event_index); >>>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >>>> /home/richard/git/linuxptp/phc2pwm.c:197:9: error: ‘pwm_chan’ may be used >>>> uninitialized in this function [-Werror=maybe-uninitialized] >>>> chan = pwm_chan_create(pwm_chip, pwm_chan); >>>> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >>>> /home/richard/git/linuxptp/phc2pwm.c:197:9: error: ‘pwm_chip’ may be used >>>> uninitialized in this function [-Werror=maybe-uninitialized] >>>> cc1: all warnings being treated as errors >>> >>> I am using 9.2 arm compiler and the build is successful. Which compiler are >>> you >>> using? >> >> gcc-linaro-7.4.1-2019.02-x86_64_arm-linux-gnueabihf > > hmm..that's old. May be time to upgrade. > >> >> Compile with -Werror please. > > I tried enabling -Werror in makefile, but the repo doesn't build at all with > the > following error: > clock.c:444:48: error: taking address of packed member of ‘struct > subscribe_events_np’ may result in an unaligned pointer value > [-Werror=address-of-packed-member] > 444 | clock_get_subscription(c, req, sen->bitmask, &sen->duration); > | ^~~~~~~~~~~~~~ > cc1: all warnings being treated as errors > <builtin>: recipe for target 'clock.o' failed >
Yep, the current code doing that is incorrect if the platform can't do unaligned access. I'm not sure what actually happens here: will the compiler for such a platform produce the right code for reading, or will it simply give up on the unaligned pointers? I know kernel code uses "get_unaligned" and "put_unaligned" to avoid this kind of issue. _______________________________________________ Linuxptp-devel mailing list Linuxptp-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-devel
