1 ; Options for the ATMEL AVR port of the compiler.
3 ; Copyright (C) 2005-2017 Free Software Foundation, Inc.
5 ; This file is part of GCC.
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22 Target Report Mask(CALL_PROLOGUES)
23 Use subroutines for function prologues and epilogues.
26 Target RejectNegative Joined Var(avr_mmcu) MissingArgError(missing device or architecture after %qs)
27 -mmcu=MCU Select the target MCU.
30 Target RejectNegative Joined Var(avr_n_flash) UInteger Init(-1)
31 Set the number of 64 KiB flash segments.
34 Target Report Mask(SKIP_BUG)
35 Indicate presence of a processor erratum.
38 Target Report Mask(RMW)
39 Enable Read-Modify-Write (RMW) instructions support/use.
42 Target Report Undocumented Mask(ALL_DEBUG)
45 Target RejectNegative Joined Undocumented Var(avr_log_details)
48 Target Report Mask(INT8)
49 Use an 8-bit 'int' type.
52 Target Report RejectNegative Mask(NO_INTERRUPTS)
53 Change the stack pointer without disabling interrupts.
56 Target Report Joined RejectNegative UInteger Var(avr_branch_cost) Init(0)
57 Set the branch costs for conditional branch instructions. Reasonable values are small, non-negative integers. The default branch cost is 0.
60 Target Report Undocumented Mask(ORDER_1)
63 Target Report Undocumented Mask(ORDER_2)
66 Target Report Mask(TINY_STACK)
67 Change only the low 8 bits of the stack pointer.
75 Make the linker relaxation machine assume that a program counter wrap-around occurs.
78 Target Report Mask(ACCUMULATE_OUTGOING_ARGS)
79 Accumulate outgoing function arguments and acquire/release the needed stack space for outpoing 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.
82 Target Report Var(avr_strict_X) Init(0)
83 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.
85 ;; For rationale behind -msp8 see explanation in avr.h.
87 Target Report RejectNegative Var(avr_sp8) Init(0)
88 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.
91 Warning C Report Var(avr_warn_addr_space_convert) Init(0)
92 Warn if the address space of an address is changed.
95 Warning C C++ Report Var(avr_warn_misspelled_isr) Init(1)
96 Warn if the ISR is misspelled, i.e. without __vector prefix. Enabled by default.
98 mfract-convert-truncate
99 Target Report Mask(FRACT_CONV_TRUNC)
100 Allow to use truncation instead of rounding towards zero for fractional fixed-point types.
103 Target Report Mask(ABSDATA)
104 Assume that all data in static storage can be accessed by LDS / STS. This option is only useful for reduced Tiny devices.
107 Driver Target Report RejectNegative
108 Do not link against the device-specific library lib<MCU>.a.