1  /* Definitions of ELF target support for Altera Nios II.
       2     Copyright (C) 2012-2023 Free Software Foundation, Inc.
       3     Contributed by Jonah Graham (jgraham@altera.com), 
       4     Will Reece (wreece@altera.com), and Jeff DaSilva (jdasilva@altera.com).
       5     Contributed by Mentor Graphics, Inc.
       6  
       7     This file is part of GCC.
       8  
       9     GCC is free software; you can redistribute it and/or modify it
      10     under the terms of the GNU General Public License as published
      11     by the Free Software Foundation; either version 3, or (at your
      12     option) any later version.
      13  
      14     GCC is distributed in the hope that it will be useful, but WITHOUT
      15     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
      16     or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
      17     License for more details.
      18  
      19     You should have received a copy of the GNU General Public License
      20     along with GCC; see the file COPYING3.  If not see
      21     <http://www.gnu.org/licenses/>.  */
      22  
      23  
      24  /* Specs to support the additional command-line options for Nios II ELF
      25     toolchains.  */
      26  
      27  /* -msmallc chooses an alternate C library.
      28     -msys-lib= specifies an additional low-level system/hosting library and
      29     is typically used to suck in a library provided by a HAL BSP.  */
      30  #undef LIB_SPEC
      31  #define LIB_SPEC \
      32  "--start-group %{msmallc: -lsmallc} %{!msmallc: -lc} -lgcc \
      33   %{msys-lib=*: -l%*} \
      34   --end-group \
      35  "
      36  
      37  /* Linking with -mhal suppresses inclusion of the GCC-provided crt* begin/end
      38     code.  Normally in this case you also link with -msys-crt0= to specify
      39     the startup code provided by the HAL BSP instead.  */
      40  #undef STARTFILE_SPEC
      41  #define STARTFILE_SPEC						\
      42    "%{mhal:"							\
      43    "%{msys-crt0=*:%*} %{!msys-crt0=*:crt0%O%s} "			\
      44    "%{msys-crt0=:%eYou need a C startup file for -msys-crt0=};"	\
      45    ":crti%O%s crtbegin%O%s}"
      46  
      47  #undef  ENDFILE_SPEC
      48  #define ENDFILE_SPEC "%{!mhal:crtend%O%s crtn%O%s}"
      49  
      50  /* The ELF target doesn't support the Nios II Linux ABI.  */
      51  #define TARGET_LINUX_ABI 0
      52  
      53  /* Default -fdelete-null-pointer-checks to off, to prevent the compiler
      54     from treating accesses to address zero as traps.  On bare-metal Nios II
      55     targets address zero may legitimately be mapped to memory (e.g., the
      56     hardware description may specify this as the address of the interrupt
      57     vector).  Users can override this on the command line to get the
      58     additional optimizations it enables.  */
      59  #define SUBTARGET_OVERRIDE_OPTIONS 		\
      60    if (flag_delete_null_pointer_checks < 0)	\
      61      flag_delete_null_pointer_checks = 0