Here is a backtrace of running guile on a builtroot constructed system for rpi3. Thumb2 instructions: BR2_ARM_INSTRUCTIONS_THUMB2=y Gcc 7.5: BR2_GCC_VERSION="7.5.0" Glibc. Uses the patch from https://gitlab.com/wingo/lightening/-/merge_requests/3 I hope this makes it through the mail client ok. -Dale Core was generated by `guile'. Program terminated with signal SIGSEGV, Segmentation fault. #0 0x76ee6f12 in ?? () [Current thread is 1 (LWP 507)] (gdb) thread apply all backtrace Thread 5 (LWP 508): #0 0x76e59674 in __libc_do_syscall () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #1 0x76e5499e in pthread_cond_wait@@GLIBC_2.4 () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #2 0x76e7d7aa in GC_wait_marker () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #3 0x76e7dab0 in GC_help_marker () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #4 0x76e7db26 in GC_mark_thread () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #5 0x76e4fbb0 in start_thread () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #6 0x76b450ec in ?? () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libc.so.6 Backtrace stopped: previous frame identical to this frame (corrupt stack?) Thread 4 (LWP 510): #0 0x76e59674 in __libc_do_syscall () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #1 0x76e5499e in pthread_cond_wait@@GLIBC_2.4 () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #2 0x76e7d7aa in GC_wait_marker () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #3 0x76e7dab0 in GC_help_marker () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #4 0x76e7db26 in GC_mark_thread () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #5 0x76e4fbb0 in start_thread () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #6 0x76b450ec in ?? () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libc.so.6 Backtrace stopped: previous frame identical to this frame (corrupt stack?) Thread 3 (LWP 511): #0 0x76e59674 in __libc_do_syscall () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #1 0x76e57720 in read () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #2 0x76ef8aee in read_finalization_pipe_data (data=0x74c1f95c) at finalizers.c:205 #3 0x76e7cea8 in GC_do_blocking_inner () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #4 0x76e7b068 in GC_with_callee_saves_pushed () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #5 0x76e7b094 in GC_do_blocking () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #6 0x76f3f10c in scm_without_guile (func=0x76ef8add , data=0x74c1f95c) at threads.c:706 #7 0x76ef8d7a in finalization_thread_proc (unused=) at finalizers.c:218 #8 0x76eef876 in c_body (d=0x74c1fe1c) at continuations.c:430 #9 0x76f4298e in vm_debug_engine (thread=0x76a46c00) at vm-engine.c:972 #10 0x76f47b9c in scm_call_n (proc=0x7521dc70, argv=argv@entry=0x74c1fbc0, nargs=nargs@entry=2) at vm.c:1608 #11 0x76ef22c4 in scm_call_2 (proc=, arg1=, arg2=) at eval.c:503 #12 0x76ef31a2 in scm_c_with_exception_handler (type=type@entry=0x404, handler=0x76f3f9b9 , handler_data=handler_data@entry=0x74c1fda8, thunk=0x76f3fa7d , thunk_data=thunk_data@entry=0x74c1fda8) at exceptions.c:170 #13 0x76f3fbd4 in scm_c_catch (tag=tag@entry=0x404, body=body@entry=0x76eef86d , body_data=body_data@entry=0x74c1fe1c, handler=handler@entry=0x76eefa1d , handler_data=handler_data@entry=0x74c1fe1c, pre_unwind_handler=pre_unwind_handler@entry=0x76eef8fb , pre_unwind_handler_data=pre_unwind_handler_data@entry=0x751fc300) at throw.c:168 --Type for more, q to quit, c to continue without paging--c #14 0x76eefba2 in scm_i_with_continuation_barrier (body=0x76eef86d , body_data=body_data@entry=0x74c1fe1c, handler=0x76eefa1d , handler_data=handler_data@entry=0x74c1fe1c, pre_unwind_handler=0x76eef8fb , pre_unwind_handler_data=0x751fc300) at continuations.c:368 #15 0x76eefc06 in scm_c_with_continuation_barrier (func=, data=) at continuations.c:464 #16 0x76f3edd4 in with_guile (base=0x74c1fe4c, data=0x74c1fe64) at threads.c:645 #17 0x76e78e98 in GC_call_with_stack_base () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #18 0x76f3f0cc in scm_i_with_guile (dynamic_state=, data=, func=) at threads.c:688 #19 scm_with_guile (func=, data=) at threads.c:694 #20 0x76e4fbb0 in start_thread () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #21 0x76b450ec in ?? () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libc.so.6 Backtrace stopped: previous frame identical to this frame (corrupt stack?) Thread 2 (LWP 509): #0 0x76e59674 in __libc_do_syscall () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #1 0x76e5499e in pthread_cond_wait@@GLIBC_2.4 () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #2 0x76e7d7aa in GC_wait_marker () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #3 0x76e7dab0 in GC_help_marker () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #4 0x76e7db26 in GC_mark_thread () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/usr/lib/libgc.so.1 #5 0x76e4fbb0 in start_thread () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libpthread.so.0 #6 0x76b450ec in ?? () from /home/dales/br/rpi/host/arm-buildroot-linux-gnueabihf/sysroot/lib/libc.so.6 Backtrace stopped: previous frame identical to this frame (corrupt stack?) Thread 1 (LWP 507): #0 0x76ee6f12 in scm_is_pair (x=0x0) at pairs.h:182 #1 scm_sloppy_assq (key=0x752076f0, alist=0x0) at alist.c:59 #2 0x76effef8 in scm_hash_fn_ref (table=table@entry=0x751da8b0, obj=obj@entry=0x752076f0, dflt=dflt@entry=0x4, hash_fn=hash_fn@entry=0x76eff79d , assoc_fn=0x76ee6f0d , closure=closure@entry=0x0) at hashtab.c:300 #3 0x76efff5c in scm_hashq_ref (table=0x751da8b0, key=key@entry=0x752076f0, dflt=0x4, dflt@entry=0x904) at hashtab.c:426 #4 0x76f11f74 in scm_module_variable (module=0x74f281e0, sym=0x752076f0) at modules.c:500 #5 0x76f430c4 in vm_debug_engine (thread=0x76a46e00) at vm-engine.c:1560 #6 0x76f47b9c in scm_call_n (proc=0x74107800, argv=argv@entry=0x7eb8fb64, nargs=nargs@entry=1) at vm.c:1608 #7 0x76ef22b0 in scm_call_1 (proc=, arg1=) at eval.c:496 #8 0x76f4298e in vm_debug_engine (thread=0x76a46e00) at vm-engine.c:972 #9 0x76f47b9c in scm_call_n (proc=0x7521dc30, argv=argv@entry=0x7eb8fdb0, nargs=nargs@entry=4) at vm.c:1608 #10 0x76ef22f4 in scm_call_4 (proc=, arg1=arg1@entry=0x751fc300, arg2=arg2@entry=0x74d09810, arg3=arg3@entry=0x76a4ab60, arg4=arg4@entry=0x7416c0b8) at eval.c:517 #11 0x76eea9a0 in scm_print_exception (port=port@entry=0x751fc300, frame=frame@entry=0x74d09810, key=key@entry=0x76a4ab60, args=args@entry=0x7416c0b8) at backtrace.c:121 #12 0x76eef994 in print_exception_and_backtrace (args=0x7416c0b8, tag=0x76a4ab60, port=0x751fc300) at continuations.c:415 #13 pre_unwind_handler (error_port=0x751fc300, tag=0x76a4ab60, args=0x7416c0b8) at continuations.c:453 #14 0x76f3fa2e in catch_pre_unwind_handler (data=0x7eb91c18, exn=0x74159fa0) at throw.c:135 #15 0x76f4298e in vm_debug_engine (thread=0x76a46e00) at vm-engine.c:972 #16 0x76f47b9c in scm_call_n (proc=proc@entry=0x7521dc50, argv=0x7eb90068, nargs=5) at vm.c:1608 #17 0x76ef245a in scm_apply_0 (proc=0x7521dc50, args=0x304) at eval.c:603 #18 0x76ef2afa in scm_apply_1 (proc=, arg1=arg1@entry=0x76a4ab60, args=args@entry=0x74d098c8) at eval.c:609 #19 0x76f3fd1c in scm_throw (key=0x76a4ab60, key@entry=0x76f8bd90 , args=0x74d098c8) at throw.c:262 #20 0x76f3fe22 in scm_ithrow (key=key@entry=0x76f8bd90 , args=, no_return=no_return@entry=1) at throw.c:457 #21 0x76ef0e66 in scm_error_scm (key=key@entry=0x76f8bd90 , subr=subr@entry=0x4, message=message@entry=0x76a4ab60, args=args@entry=0x304, data=0x74d09948) at error.c:90 #22 0x76f41c4a in bind_kwargs (thread=, npositional=, nlocals=14, kwargs=0x75145ce0, strict=1 '01', allow_other_keys=0 '00') at vm.c:1015 #23 0x7500c6e4 in ?? () Backtrace stopped: previous frame identical to this frame (corrupt stack?) (gdb) info reg r0 0x752076f0 1965061872 r1 0x0 0 r2 0x0 0 r3 0x76ee6f0d 1995337485 r4 0x4 4 r5 0x76f7c000 1995948032 r6 0x751da8b0 1964878000 r7 0x752076f0 1965061872 r8 0x3 3 r9 0x74c6d160 1959186784 r10 0x76f8c7e4 1996015588 r11 0x76f7c000 1995948032 r12 0x76f7c288 1995948680 sp 0x7eb8f8d8 0x7eb8f8d8 lr 0x76effef9 1995439865 pc 0x76ee6f12 0x76ee6f12 cpsr 0x40000030 1073741872 fpscr 0x0 0 (gdb) disassem /r 0x76ee6f12,+8 Dump of assembler code from 0x76ee6f12 to 0x76ee6f1a: => 0x76ee6f12 : 0b 68 ldr r3, [r1, #0] 0x76ee6f14 : da 07 lsls r2, r3, #31 0x76ee6f16 : 0a d4 bmi.n 0x76ee6f2e 0x76ee6f18 : 13 f0 06 0f tst.w r3, #6 End of assembler dump.