Thanks Ian for the very quick reply! I see you're referencing this:
> On ARM, x86-32, and 32-bit MIPS, it is the caller's responsibility to arrange for 64-bit alignment of 64-bit words accessed atomically. The first word in a variable or in an allocated struct, array, or slice can be relied upon to be 64-bit aligned. Yeah it's a little unfortunate that it doesn't say i386, I ctrl-f'd for "i386" on the page too and I probably would have correctly read that sentence if it were in there. Unfortunately I read that sentence multiple times but I guess I missed the obvious "x86" in there; my brain saw "ARM 32 32-bit MIPS" and misread it as "32-bit ARM and 32-bit MIPS". My mistake for sure. Thanks again, Kevin On Friday, November 20, 2020 at 1:54:28 PM UTC-7 Ian Lance Taylor wrote: > On Fri, Nov 20, 2020 at 12:48 PM 'Kevin Chowski' via golang-nuts > <golan...@googlegroups.com> wrote: > > > > I am debugging an issue in which we are seeing a crash on an atomic > access; on go 1.14.7 and 1.15.2 this reproduces with the following error: > > > > > panic: runtime error: invalid memory address or nil pointer dereference > > > [signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x8049f7c] > > > > On gotip (go version devel +3fd4917 Fri Nov 20 20:02:47 2020 +0000 > linux/amd64) I see the following instead: > > > > > panic: unaligned 64-bit atomic operation > > > > (I'm glad the error message got better! Kudos to whomever did that.) > > > > My confusion is that I don't quite see this restriction being documented > in sync/atomic's docs: ctrl-f for "alignment" only reveals information > related to MIPS and ARM, whereas this issue is for Intel 386. Is this > working as intended (e.g. documentation bug) or is this something deeper? > > It's down at the very bottom of https://golang.org/pkg/sync/atomic, in > the "Bugs" section, which for some reason refers to i386 using the > name x86-32. > > Ian > -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/golang-nuts/b92e1561-441a-4ff3-8d7c-6929801a0b9bn%40googlegroups.com.
