; Options for the ATMEL AVR port of the compiler. ; Copyright (C) 2005-2018 Free Software Foundation, Inc. ; ; This file is part of GCC. ; ; GCC is free software; you can redistribute it and/or modify it under ; the terms of the GNU General Public License as published by the Free ; Software Foundation; either version 3, or (at your option) any later ; version. ; ; GCC is distributed in the hope that it will be useful, but WITHOUT ANY ; WARRANTY; without even the implied warranty of MERCHANTABILITY or ; FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License ; for more details. ; ; You should have received a copy of the GNU General Public License ; along with GCC; see the file COPYING3. If not see ; . mcall-prologues Target Report Mask(CALL_PROLOGUES) Use subroutines for function prologues and epilogues. mmcu= Target RejectNegative Joined Var(avr_mmcu) MissingArgError(missing device or architecture after %qs) -mmcu=MCU Select the target MCU. mgas-isr-prologues Target Report Var(avr_gasisr_prologues) UInteger Init(0) Allow usage of __gcc_isr pseudo instructions in ISR prologues and epilogues. mn-flash= Target RejectNegative Joined Var(avr_n_flash) UInteger Init(-1) Set the number of 64 KiB flash segments. mskip-bug Target Report Mask(SKIP_BUG) Indicate presence of a processor erratum. mrmw Target Report Mask(RMW) Enable Read-Modify-Write (RMW) instructions support/use. mdeb Target Report Undocumented Mask(ALL_DEBUG) mlog= Target RejectNegative Joined Undocumented Var(avr_log_details) mshort-calls Target Report RejectNegative Mask(SHORT_CALLS) Use RJMP / RCALL even though CALL / JMP are available. mint8 Target Report Mask(INT8) Use an 8-bit 'int' type. mno-interrupts Target Report RejectNegative Mask(NO_INTERRUPTS) Change the stack pointer without disabling interrupts. mbranch-cost= Target Report Joined RejectNegative UInteger Var(avr_branch_cost) Init(0) Set the branch costs for conditional branch instructions. Reasonable values are small, non-negative integers. The default branch cost is 0. mmain-is-OS_task Target Report Mask(MAIN_IS_OS_TASK) Treat main as if it had attribute OS_task. morder1 Target Report Undocumented Mask(ORDER_1) morder2 Target Report Undocumented Mask(ORDER_2) mtiny-stack Target Report Mask(TINY_STACK) Change only the low 8 bits of the stack pointer. mrelax Target Report Relax branches. mpmem-wrap-around Target Report Make the linker relaxation machine assume that a program counter wrap-around occurs. maccumulate-args Target Report Mask(ACCUMULATE_OUTGOING_ARGS) 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. mstrict-X Target Report Var(avr_strict_X) Init(0) 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. ;; For rationale behind -msp8 see explanation in avr.h. msp8 Target Report RejectNegative Var(avr_sp8) Init(0) 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. Waddr-space-convert Warning C Report Var(avr_warn_addr_space_convert) Init(0) Warn if the address space of an address is changed. Wmisspelled-isr Warning C C++ Report Var(avr_warn_misspelled_isr) Init(1) Warn if the ISR is misspelled, i.e. without __vector prefix. Enabled by default. mfract-convert-truncate Target Report Mask(FRACT_CONV_TRUNC) Allow to use truncation instead of rounding towards zero for fractional fixed-point types. mabsdata Target Report Mask(ABSDATA) Assume that all data in static storage can be accessed by LDS / STS. This option is only useful for reduced Tiny devices. nodevicelib Driver Target Report RejectNegative Do not link against the device-specific library lib.a.