https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109374
--- Comment #5 from John David Anglin <danglin at gcc dot gnu.org> --- I'm not sure what is expected here: (gdb) r Starting program: /home/dave/gnu/gcc/objdir/gcc/testsuite/gnat/div_zero.exe warning: Unable to find libthread_db matching inferior's thread library, thread debugging will not be available. Program received signal SIGFPE, Arithmetic exception. $$divoI () at ../../../gcc/libgcc/config/pa/milli64.S:448 448 addit,= 0,arg1,r0 /* trap if divisor == 0 */ (gdb) c Continuing. Breakpoint 1, __gnat_error_handler (sig=8, si=0xf8f02488, ucontext=0xf8f02508) at init.c:538 538 now, before we possibly trigger a recursive fault below. */ (gdb) p/x ((ucontext_t *) ucontext)->uc_mcontext.sc_iaoq[0] $2 = 0x1d1bf (gdb) bt #0 __gnat_error_handler (sig=8, si=0xf8f02488, ucontext=0xf8f02508) at init.c:538 #1 <signal handler called> #2 $$divoI () at ../../../gcc/libgcc/config/pa/milli64.S:448 #3 0x0001a124 in div_zero () (gdb) frame 2 #2 $$divoI () at ../../../gcc/libgcc/config/pa/milli64.S:448 448 addit,= 0,arg1,r0 /* trap if divisor == 0 */ (gdb) disass $pc-16,$pc+16 Dump of assembler code from 0x1d1ac to 0x1d1cc: 0x0001d1ac <$$divoI+428>: bv,n r0(r31) 0x0001d1b0 <$$divoI+432>: nop 0x0001d1b4 <$$divoI+436>: blr,n r25,r0 0x0001d1b8 <$$divoI+440>: nop => 0x0001d1bc <$$divoI+444>: addi,tc,= 0,r25,r0 0x0001d1c0 <$$divoI+448>: nop 0x0001d1c4 <$$divoI+452>: bv r0(r31) 0x0001d1c8 <$$divoI+456>: copy r26,ret1 End of assembler dump. (gdb) frame 0 #0 __gnat_error_handler (sig=8, si=0xf8f02488, ucontext=0xf8f02508) at init.c:538 538 now, before we possibly trigger a recursive fault below. */ (gdb) ptype ((ucontext_t *) ucontext)->uc_mcontext.sc_iaoq[0] type = unsigned long As things stands, the pc (head iaoq value) points at the nop after the addi,tc,= which caused the trap. As far as I can tell, this test has always failed on both 32-bit linux and hpux.
