gcc/config/avr/avr.opt

   1 ; Options for the ATMEL AVR port of the compiler.
   2
   3 ; Copyright (C) 2005-2018 Free Software Foundation, Inc.
   4 ;
   5 ; This file is part of GCC.
   6 ;
   7 ; GCC is free software; you can redistribute it and/or modify it under
   8 ; the terms of the GNU General Public License as published by the Free
   9 ; Software Foundation; either version 3, or (at your option) any later
  10 ; version.
  11 ;
  12 ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 ; WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 ; FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 ; for more details.
  16 ;
  17 ; You should have received a copy of the GNU General Public License
  18 ; along with GCC; see the file COPYING3.  If not see
  19 ; <http://www.gnu.org/licenses/>.
  20
  21 mcall-prologues
  22 Target Report Mask(CALL_PROLOGUES)
  23 Use subroutines for function prologues and epilogues.
  24
  25 mmcu=
  26 Target RejectNegative Joined Var(avr_mmcu) MissingArgError(missing device or architecture after %qs)
  27 -mmcu=MCU       Select the target MCU.
  28
  29 mgas-isr-prologues
  30 Target Report Var(avr_gasisr_prologues) UInteger Init(0)
  31 Allow usage of __gcc_isr pseudo instructions in ISR prologues and epilogues.
  32
  33 mn-flash=
  34 Target RejectNegative Joined Var(avr_n_flash) UInteger Init(-1)
  35 Set the number of 64 KiB flash segments.
  36
  37 mskip-bug
  38 Target Report Mask(SKIP_BUG)
  39 Indicate presence of a processor erratum.
  40
  41 mrmw
  42 Target Report Mask(RMW)
  43 Enable Read-Modify-Write (RMW) instructions support/use.
  44
  45 mdeb
  46 Target Report Undocumented Mask(ALL_DEBUG)
  47
  48 mlog=
  49 Target RejectNegative Joined Undocumented Var(avr_log_details)
  50
  51 mshort-calls
  52 Target Report RejectNegative Mask(SHORT_CALLS)
  53 Use RJMP / RCALL even though CALL / JMP are available.
  54
  55 mint8
  56 Target Report Mask(INT8)
  57 Use an 8-bit 'int' type.
  58
  59 mno-interrupts
  60 Target Report RejectNegative Mask(NO_INTERRUPTS)
  61 Change the stack pointer without disabling interrupts.
  62
  63 mbranch-cost=
  64 Target Report Joined RejectNegative UInteger Var(avr_branch_cost) Init(0)
  65 Set the branch costs for conditional branch instructions.  Reasonable values are small, non-negative integers.  The default branch cost is 0.
  66
  67 mmain-is-OS_task
  68 Target Report Mask(MAIN_IS_OS_TASK)
  69 Treat main as if it had attribute OS_task.
  70
  71 morder1
  72 Target Report Undocumented Mask(ORDER_1)
  73
  74 morder2
  75 Target Report Undocumented Mask(ORDER_2)
  76
  77 mtiny-stack
  78 Target Report Mask(TINY_STACK)
  79 Change only the low 8 bits of the stack pointer.
  80
  81 mrelax
  82 Target Report
  83 Relax branches.
  84
  85 mpmem-wrap-around
  86 Target Report
  87 Make the linker relaxation machine assume that a program counter wrap-around occurs.
  88
  89 maccumulate-args
  90 Target Report Mask(ACCUMULATE_OUTGOING_ARGS)
  91 Accumulate outgoing function arguments and acquire/release the needed stack space for outgoing function arguments in function prologue/epilogue.  Without this option, outgoing arguments are pushed before calling a function and popped afterwards.  This option can lead to reduced code size for functions that call many functions that get their arguments on the stack like, for example printf.
  92
  93 mstrict-X
  94 Target Report Var(avr_strict_X) Init(0)
  95 When accessing RAM, use X as imposed by the hardware, i.e. just use pre-decrement, post-increment and indirect addressing with the X register.  Without this option, the compiler may assume that there is an addressing mode X+const similar to Y+const and Z+const and emit instructions to emulate such an addressing mode for X.
  96
  97 ;; For rationale behind -msp8 see explanation in avr.h.
  98 msp8
  99 Target Report RejectNegative Var(avr_sp8) Init(0)
 100 The device has no SPH special function register. This option will be overridden by the compiler driver with the correct setting if presence/absence of SPH can be deduced from -mmcu=MCU.
 101
 102 Waddr-space-convert
 103 Warning C Report Var(avr_warn_addr_space_convert) Init(0)
 104 Warn if the address space of an address is changed.
 105
 106 Wmisspelled-isr
 107 Warning C C++ Report Var(avr_warn_misspelled_isr) Init(1)
 108 Warn if the ISR is misspelled, i.e. without __vector prefix. Enabled by default.
 109
 110 mfract-convert-truncate
 111 Target Report Mask(FRACT_CONV_TRUNC)
 112 Allow to use truncation instead of rounding towards zero for fractional fixed-point types.
 113
 114 mabsdata
 115 Target Report Mask(ABSDATA)
 116 Assume that all data in static storage can be accessed by LDS / STS.  This option is only useful for reduced Tiny devices.
 117
 118 nodevicelib
 119 Driver Target Report RejectNegative
 120 Do not link against the device-specific library lib<MCU>.a.