An application using SDL1 on ubuntu 16.04 fails with the following: vex amd64->IR: unhandled instruction bytes: 0xC5 0xFC 0xC2 0xC0 0xF 0xC4 0xC2 0x7D 0x18 0x49 vex amd64->IR: REX=0 REX.W=0 REX.R=0 REX.X=0 REX.B=0 vex amd64->IR: VEX=1 VEX.L=1 VEX.nVVVV=0x0 ESC=0F vex amd64->IR: PFX.66=0 PFX.F2=0 PFX.F3=0 ==38658== valgrind: Unrecognised instruction at address 0xa324512. ==38658== at 0xA324512: ??? ==38658== by 0x1B35B177: ??? (in /usr/lib/x86_64-linux-gnu/dri/swrast_dri.so) ==38658== by 0x1B35B4E8: ??? (in /usr/lib/x86_64-linux-gnu/dri/swrast_dri.so) ==38658== by 0x1B35BBC3: ??? (in /usr/lib/x86_64-linux-gnu/dri/swrast_dri.so) ==38658== by 0x1B35B9E6: ??? (in /usr/lib/x86_64-linux-gnu/dri/swrast_dri.so) ==38658== by 0xCC7A6B9: start_thread (pthread_create.c:333) ==38658== by 0xF98241C: clone (clone.S:109) Unfortunately there is no matching *-dbg or *-dbgsym package I can install so there's no info on what line causes this.
The matching *-dbgsym package just showed up and there's a useful stack trace now ==45626== valgrind: Unrecognised instruction at address 0xa324512. ==45626== at 0xA324512: ??? ==45626== by 0x1B35B177: lp_rast_shade_tile (lp_rast.c:352) ==45626== by 0x1B35B4E8: do_rasterize_bin (lp_rast.c:609) ==45626== by 0x1B35B4E8: rasterize_bin (lp_rast.c:628) ==45626== by 0x1B35B4E8: rasterize_scene (lp_rast.c:688) ==45626== by 0x1B35BBC3: thread_function (lp_rast.c:829) ==45626== by 0x1B35B9E6: impl_thrd_routine (threads_posix.h:87) ==45626== by 0xCC7A6B9: start_thread (pthread_create.c:333) ==45626== by 0xF98241C: clone (clone.S:109) Unfortunately that is not that helpful since the code at that line is a call to the JIT variant->jit_function[RAST_WHOLE]( &state->jit_context, tile_x + x, tile_y + y, inputs->frontfacing, GET_A0(inputs), GET_DADX(inputs), GET_DADY(inputs), color, depth, 0xffff, &task->thread_data, stride, depth_stride);