If I flash helix with recent gecko/gaia builds, then once the device starts properly, I see: 17:42:01 ➜ 039_helix git:(master) ✗ adb shell b2g-ps APPLICATION USER PID PPID VSIZE RSS WCHAN PC NAME b2g root 166 1 201376 68480 ffffffff 400b2804 S /system/b2g/b2g (Nuwa) root 377 166 54780 20196 ffffffff 400fc804 S /system/b2g/plugin-container Communications app_429 429 377 1244668 37016 ffffffff 400fc804 R /system/b2g/plugin-container Homescreen app_531 531 377 132792 41620 ffffffff 400fc804 S /system/b2g/plugin-container (Preallocated a root 614 377 62964 19800 ffffffff 400fc804 S /system/b2g/plugin-container Since I am trying to debug an app start-up problem, I do: ./run-gdb.sh attach 614 ...and type 'c' [Enter] to continue the pre-allocated process. If I then touch the Camera app icon, the process borks out with: Program received signal SIGSEGV, Segmentation fault. 0xb0005462 in unwind_phase2_forced (ucbp=0x6f6e00, entry_vrs=0x1f, resuming=-1342075088) at /tmp/android-build-bb7e003d31d08f72cabc269a652912b7/src/build/../gcc/gcc-4.4.3/libgcc/../gcc/config/arm/unwind-arm.c:717 717 /tmp/android-build-bb7e003d31d08f72cabc269a652912b7/src/build/../gcc/gcc-4.4.3/libgcc/../gcc/config/arm/unwind-arm.c: No such file or directory. in /tmp/android-build-bb7e003d31d08f72cabc269a652912b7/src/build/../gcc/gcc-4.4.3/libgcc/../gcc/config/arm/unwind-arm.c (gdb) bt #0 0xb0005462 in unwind_phase2_forced (ucbp=0x6f6e00, entry_vrs=0x1f, resuming=-1342075088) at /tmp/android-build-bb7e003d31d08f72cabc269a652912b7/src/build/../gcc/gcc-4.4.3/libgcc/../gcc/config/arm/unwind-arm.c:717 #1 0x4000e000 in ?? () Cannot access memory at address 0xab #2 0x4000e000 in ?? () Cannot access memory at address 0xab Backtrace stopped: previous frame identical to this frame (corrupt stack?) The process can't continue: (gdb) c Continuing. Program received signal SIGSEGV, Segmentation fault. 0xb0005462 in unwind_phase2_forced (ucbp=0x6f6e00, entry_vrs=0x1f, resuming=-1342075088) at /tmp/android-build-bb7e003d31d08f72cabc269a652912b7/src/build/../gcc/gcc-4.4.3/libgcc/../gcc/config/arm/unwind-arm.c:717 717 in /tmp/android-build-bb7e003d31d08f72cabc269a652912b7/src/build/../gcc/gcc-4.4.3/libgcc/../gcc/config/arm/unwind-arm.c (gdb) c Continuing. Child terminated with signal = 0xb (SIGSEGV) ...and eventually terminates.

MOZ_DEBUG_CHILD_PROCESS=1 doesn't work either. 17:48:21 ➜ 039_helix git:(master) ✗ MOZ_DEBUG_CHILD_PROCESS=1 ./run-gdb.sh B2G_DEBUG = 0 B2G_NOOPT = 0 MOZ_DMD = 0 REFCNT_LOGGING = 0 ENABLE_PROFILING = 0 GECKO_PATH = /home/mikeh/dev/mozilla/m-c/b2g-inbound GECKO_OBJDIR = /home/mikeh/dev/mozilla/b2g/039_helix/objdir-gecko-b2g-inbound ..ignoring gdbserver pid 838 Using DMD. Process /system/b2g/b2g created; pid = 2400 Listening on port 11000 prebuilt/linux-x86/toolchain/arm-linux-androideabi-4.4.x/bin/arm-linux-androideabi-gdb -x /tmp/b2g.gdbinit.mikeh.1856 /home/mikeh/dev/mozilla/b2g/039_helix/objdir-gecko-b2g-inbound/dist/bin/b2g GNU gdb (GDB) 7.1-android-gg2 Copyright (C) 2010 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "--host=i686-linux-gnu --target=arm-elf-linux". For bug reporting instructions, please see: <http://www.gnu.org/software/gdb/bugs/>... Reading symbols from /home/mikeh/dev/mozilla/b2g/039_helix/objdir-gecko-b2g-inbound/dist/bin/b2g...done. Remote debugging from host 127.0.0.1 __dl__start () at bionic/linker/arch/arm/begin.S:35 35 mov r0, sp (gdb) c Continuing. 1383320641351 Marionette INFO marionette enabled via build flag and pref 1383320642101 Marionette INFO marionette-server.js loaded 1383320642336 Marionette INFO B2G emulator: no 1383320642337 Marionette INFO Device detected is HUAWEI Y300-F1 1383320642340 Marionette INFO Listening on port 2828 1383320642341 Marionette INFO Marionette server ready Program received signal SIGSEGV, Segmentation fault. 0x4005e9bc in ?? () (gdb) bt #0 0x4005e9bc in ?? () #1 0x4005ed62 in ?? () Backtrace stopped: previous frame identical to this frame (corrupt stack?) (gdb)

Copying a few comments from #b2g: 13:35 < jld> mikeh: I've seen that before. 13:36 < jld> mikeh: Somehow the EH code goes out-of-bounds on the exception index table. This *might* be related to the linker bug that give libc a not-quite-sorted index. 13:36 < jld> mikeh: The other question is... why are we in the EH code? 13:37 < jld> mikeh: There are definitely weird things that happen when the libc and ld.so that gdb sees aren't the ones on the device. 13:38 < jld> mikeh: I know things tended to break in the code in ld.so that's supposed to inform gdb of library loading. 13:39 < jld> mikeh: So, if I was debugging the main process and started the Email app (which causes the parent to load NSS and dlopen the PKCS#11 module), it would break. 13:40 < mikeh> jld: that's consistent with what I'm seeing--the camera app causes a load of the camera driver library (though I thought that was in another process).

Firefox OS is not being worked on