[Bug c/47597] New: ICE: call frame debugging information is not handled when case is post_dec

[anitha.boyapati at atmel dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=47597

           Summary: ICE: call frame debugging information is not handled
                    when case is post_dec
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: anitha.boyapati@atmel.com


When a register is saved onto the stack, the relevant call frame debugging
information is not recorded in dwarf2out_frame_debug_expr() when stack follows
post_dec mode. As a result, targets whose STACK_PUSH_CODE is POST_DEC. An ICE
is observed when built for AVR target. Debugging shows that gcc_unreachable()
is called in MEM case. 

The version of gcc used for testing is 4.4.3. But this support is not seen in
even the current latest version 169036 (line numbers: 2568 to 2678)

http://gcc.gnu.org/viewcvs/trunk/gcc/dwarf2out.c?revision=169036&view=markup

The host environment is  x86_64 GNU/Linux. Target build is for AVR.