> I'm trying to understand what you mean, but your comments are rather > obscure. Which file do you think I should change? Just tell me where to > look and I'll do it.
glibc/ports/sysdeps/unix/sysv/linux/arm/eabi/sigrestorer.S Currently has: .fnstart .save {r0-r15} .pad #32 nop ENTRY(__default_sa_restorer_v2) mov r7, $SYS_ify(sigreturn) swi 0x0 .fnend This needs changing to: .fnstart .personality __gnu_personality_sigframe nop ENTRY(__default_sa_restorer_v2) mov r7, $SYS_ify(sigreturn) swi 0x0 .fnend The implementation of __gnu_personality_sigframe looks something like: #include <unwind.h> static void adjust_sp(context, int n) { _Unwind_Word sp; _Unwind_VRS_Get (context, _UVRSC_CORE, R_SP, _UVRSD_UINT32, &sp); sp += n; _Unwind_VRS_Set (context, _UVRSC_CORE, R_SP, _UVRSD_UINT32, &sp); } static uint32_t get_cpsr(context) { return sp[...]; } _Unwind_Reason_Code __gnu_personality_sigframe (_Unwind_State state, _Unwind_Control_Block *ucbp, _Unwind_Context *context) { int reg; uint32_t cpsr; uint32_t pc; uint32_t *sp; /* We never have any handlers or cleanups. Just Unwind the signal frame and keep going. */ _Unwind_VRS_Get (context, _UVRSC_CORE, R_SP, _UVRSD_UINT32, &sp); sp -= ...; if (GLRO (dl_hwcap) & HWCAP_ARM_VFP) { foreach(vfp_reg) _Unwind_VRS_Set(context, _UVRSC_VFP, ..., _UVRSD_DOUBLE, &sp[...]); /* Don't forget about VFP3 (i.e. D16-D31 if they exist). */ } foreach(core_reg) _Unwind_VRS_Set (context, _UVRSC_CORE, ..., _UVRSD_UINT32, &sp[...]); pc = sp[...]; cpsr = sp[...]; /* Set mode bit from saved CPSR. */ pc &= ~1; if (cpsr & CPSR_T) pc |= 1; /* Advance PC past the faulting instruction. */ if ((cpsr & CPSR_T) && (*(uint16_t *)(pc & ~1) < 0xe800)) pc += 2; else pc += 4; _Unwind_VRS_Set (context, _UVRSC_CORE, R_PC, _UVRSD_UINT32, &pc); /* We don't/can't restore CPSR and FPSR. However the EABI requires these have fixed values at public entry points. Hope that subsequent catch/cleanup handlers are ok with that value. */ return _URC_CONTINUE_UNWIND; } For bonus points have __gnu_personality_sigframe automagically handle bit old and new layouts, removing the _v1/_v2 hacks. Paul